Printed Electronic Devices in Human Spaceflight

NASA Technical Reports Server (NTRS)

Bacon, John B.

2004-01-01

The space environment requires robust sensing, control, and automation, whether in support of human spaceflight or of robotic exploration. Spaceflight embodies the known extremes of temperature, radiation, shock, vibration, and static loads, and demands high reliability at the lowest possible mass. Because printed electronic circuits fulfill all these requirements, printed circuit technology and the exploration of space have been closely coupled throughout their short histories. In this presentation, we will explore the space (and space launch) environments as drivers of printed circuit design, a brief history of NASA's use of printed electronic circuits, and we will examine future requirements for such circuits in our continued exploration of space.

Apparatus And Method Of Using Flexible Printed Circuit Board In Optical Transceiver Device

DOEpatents

Anderson, Gene R.; Armendariz, Marcelino G.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reysen, Bill H.

2005-03-15

This invention relates to a flexible printed circuit board that is used in connection with an optical transmitter, receiver or transceiver module. In one embodiment, the flexible printed circuit board has flexible metal layers in between flexible insulating layers, and the circuit board comprises: (1) a main body region orientated in a first direction having at least one electrical or optoelectronic device; (2) a plurality of electrical contact pads integrated into the main body region, where the electrical contact pads function to connect the flexible printed circuit board to an external environment; (3) a buckle region extending from one end of the main body region; and (4) a head region extending from one end of the buckle region, and where the head region is orientated so that it is at an angle relative to the direction of the main body region. The electrical contact pads may be ball grid arrays, solder balls or land-grid arrays, and they function to connect the circuit board to an external environment. A driver or amplifier chip may be adapted to the head region of the flexible printed circuit board. In another embodiment, a heat spreader passes along a surface of the head region of the flexible printed circuit board, and a window is formed in the head region of the flexible printed circuit board. Optoelectronic devices are adapted to the head spreader in such a manner that they are accessible through the window in the flexible printed circuit board.

Three-Dimensional, Inkjet-Printed Organic Transistors and Integrated Circuits with 100% Yield, High Uniformity, and Long-Term Stability.

PubMed

Kwon, Jimin; Takeda, Yasunori; Fukuda, Kenjiro; Cho, Kilwon; Tokito, Shizuo; Jung, Sungjune

2016-11-22

In this paper, we demonstrate three-dimensional (3D) integrated circuits (ICs) based on a 3D complementary organic field-effect transistor (3D-COFET). The transistor-on-transistor structure was achieved by vertically stacking a p-type OFET over an n-type OFET with a shared gate joining the two transistors, effectively halving the footprint of printed transistors. All the functional layers including organic semiconductors, source/drain/gate electrodes, and interconnection paths were fully inkjet-printed except a parylene dielectric which was deposited by chemical vapor deposition. An array of printed 3D-COFETs and their inverter logic gates comprising over 100 transistors showed 100% yield, and the uniformity and long-term stability of the device were also investigated. A full-adder circuit, the most basic computing unit, has been successfully demonstrated using nine NAND gates based on the 3D structure. The present study fulfills the essential requirements for the fabrication of organic printed complex ICs (increased transistor density, 100% yield, high uniformity, and long-term stability), and the findings can be applied to realize more complex digital/analogue ICs and intelligent devices.

Organic printed photonics: From microring lasers to integrated circuits

PubMed Central

Zhang, Chuang; Zou, Chang-Ling; Zhao, Yan; Dong, Chun-Hua; Wei, Cong; Wang, Hanlin; Liu, Yunqi; Guo, Guang-Can; Yao, Jiannian; Zhao, Yong Sheng

2015-01-01

A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 105, which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices. PMID:26601256

Organic printed photonics: From microring lasers to integrated circuits.

PubMed

Zhang, Chuang; Zou, Chang-Ling; Zhao, Yan; Dong, Chun-Hua; Wei, Cong; Wang, Hanlin; Liu, Yunqi; Guo, Guang-Can; Yao, Jiannian; Zhao, Yong Sheng

2015-09-01

A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 10(5), which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices.

Adult Competency Education Kit. Basic Skills in Speaking, Math, and Reading for Employment. Part P: ACE Competency Based Job Descriptions: #77--Secretary; #78--Keypunch Operator; Assembly Worker Core Job Description; #82--Electronics Assembler; #83--Printed Circuit Assembler; #84--Micro Electronics Assembler; #85--Chassis Assembler; #87--Machinist Apprentice.

ERIC Educational Resources Information Center

San Mateo County Office of Education, Redwood City, CA. Career Preparation Centers.

This thirteenth of fifteen sets of Adult Competency Education (ACE) Competency Based Job Descriptions in the ACE kit contains job descriptions for Secretary, Keypunch Operator, Electronics Assembler, Printed Circuit Assembler, Micro Electronincs Assembler, Chassis Assembler, and Machinist Apprentice. Each begins with a fact sheet that includes…

Printed stretchable circuit on soft elastic substrate for wearable application

NASA Astrophysics Data System (ADS)

Yuan, Wei; Wu, Xinzhou; Gu, Weibing; Lin, Jian; Cui, Zheng

2018-01-01

In this paper, a flexible and stretchable circuit has been fabricated by the printing method based on Ag NWs/PDMS composite. The randomly oriented Ag NWs were buried in PDMS to form a conductive and stretchable electrode. Stable conductivity was achieved with a large range of tensile strain (0-50%) after the initial stretching/releasing cycle. The stable electrical response is due to the buckling of the Ag NWs/PDMS composite layer. Furthermore, printed stretchable circuits integrated with commercial ICs have been demonstrated for wearable applications. Project supported by the National Program on Key Basic Research Project (No. 2015CB351901), the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDA09020201), and the National Science Foundation of China (Nos. 51603227, 51603228).

A Formal Algorithm for Routing Traces on a Printed Circuit Board

NASA Technical Reports Server (NTRS)

Hedgley, David R., Jr.

1996-01-01

This paper addresses the classical problem of printed circuit board routing: that is, the problem of automatic routing by a computer other than by brute force that causes the execution time to grow exponentially as a function of the complexity. Most of the present solutions are either inexpensive but not efficient and fast, or efficient and fast but very costly. Many solutions are proprietary, so not much is written or known about the actual algorithms upon which these solutions are based. This paper presents a formal algorithm for routing traces on a print- ed circuit board. The solution presented is very fast and efficient and for the first time speaks to the question eloquently by way of symbolic statements.

Compact, high-speed algorithm for laying out printed circuit board runs

NASA Astrophysics Data System (ADS)

Zapolotskiy, D. Y.

1985-09-01

A high speed printed circuit connection layout algorithm is described which was developed within the framework of an interactive system for designing two-sided printed circuit broads. For this reason, algorithm speed was considered, a priori, as a requirement equally as important as the inherent demand for minimizing circuit run lengths and the number of junction openings. This resulted from the fact that, in order to provide psychological man/machine compatibility in the design process, real-time dialog during the layout phase is possible only within limited time frames (on the order of several seconds) for each circuit run. The work was carried out for use on an ARM-R automated work site complex based on an SM-4 minicomputer with a 32K-word memory. This limited memory capacity heightened the demand for algorithm speed and also tightened data file structure and size requirements. The layout algorithm's design logic is analyzed. The structure and organization of the data files are described.

Vibration analysis of printed circuit boards: Effect of boundary condition

NASA Astrophysics Data System (ADS)

Prashanth, M. D.

2018-04-01

A spacecraft consists of a number of electronic packages to meet the functional requirements. An electronic package is generally an assembly of printed circuit boards placed in a mechanical housing. A number of electronic components are mounted on the printed circuit board (PCB). A spacecraft experiences various types of loads during its launch such as vibration, acoustic and shock loads. Prediction of response for printed circuit boards due to vibration loads is important for mechanical design and reliability of electronic packages. The modeling and analysis of printed circuit boards is required for accurate prediction of response due to vibration loads. The response of PCB is highly dependent on the mounting configuration of PCB. In addition, anti-vibration mounts or stiffeners are used to reduce the PCB response. Vibration analysis of printed circuit boards is carried out using finite element method. The objective of this paper is to determine the dynamic characteristics of a printed circuit board. Modeling and analysis of PCB shall be carried out to study the effect of boundary conditions on the vibration response. The modeling of stiffeners or ribs shall also be considered in detail. The analysis results shall be validated using vibration tests of PCB.

Reliability Assessment of Critical Electronic Components

DTIC Science & Technology

1992-07-01

Failures FLHP - Full Horse Power FSN - Federal Stock Number I Current IC - Integrated Circuit IPB - Illustrated Parts Breakdown K - Boltzmans Constant L...Classified P - Power PC - Printed Circuit PCB - Printed Circuit Board PGA - Pin Grid Array PPM - Parts Per Million PWB - Printed Wiring Board 0...4-59 4.4.3.2.3 Circuit Brcakers ......................................................... 4-59 4.4.3.2.4 Thermal

Sorting of large-diameter semiconducting carbon nanotube and printed flexible driving circuit for organic light emitting diode (OLED)

NASA Astrophysics Data System (ADS)

Xu, Wenya; Zhao, Jianwen; Qian, Long; Han, Xianying; Wu, Liangzhuan; Wu, Weichen; Song, Minshun; Zhou, Lu; Su, Wenming; Wang, Chao; Nie, Shuhong; Cui, Zheng

2014-01-01

A novel approach was developed to sort a large-diameter semiconducting single-walled carbon nanotube (sc-SWCNT) based on copolyfluorene derivative with high yield. High purity sc-SWCNTs inks were obtained by wrapping arc-discharge SWCNTs with poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) aided by sonication and centrifugation in tetrahydrofuran (THF). The sorted sc-SWCNT inks and nanosilver inks were used to print top-gated thin-film transistors (TFTs) on flexible substrates with an aerosol jet printer. The printed TFTs demonstrated low operating voltage, small hysteresis, high on-state current (up to 10-3 A), high mobility and on-off ratio. An organic light emitting diode (OLED) driving circuit was constructed based on the printed TFTs, which exhibited high on-off ratio up to 104 and output current up to 3.5 × 10-4 A at Vscan = -4.5 V and Vdd = 0.8 V. A single OLED was switched on with the driving circuit, showing the potential as backplanes for active matrix OLED applications.A novel approach was developed to sort a large-diameter semiconducting single-walled carbon nanotube (sc-SWCNT) based on copolyfluorene derivative with high yield. High purity sc-SWCNTs inks were obtained by wrapping arc-discharge SWCNTs with poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) aided by sonication and centrifugation in tetrahydrofuran (THF). The sorted sc-SWCNT inks and nanosilver inks were used to print top-gated thin-film transistors (TFTs) on flexible substrates with an aerosol jet printer. The printed TFTs demonstrated low operating voltage, small hysteresis, high on-state current (up to 10-3 A), high mobility and on-off ratio. An organic light emitting diode (OLED) driving circuit was constructed based on the printed TFTs, which exhibited high on-off ratio up to 104 and output current up to 3.5 × 10-4 A at Vscan = -4.5 V and Vdd = 0.8 V. A single OLED was switched on with the driving circuit, showing the potential as backplanes for active matrix OLED applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr04870e

An innovative approach to predict technology evolution for the desoldering of printed circuit boards: A perspective from China and America.

PubMed

Wang, Chen; Zhao, Wu; Wang, Jie; Chen, Ling; Luo, Chun-Jing

2016-06-01

The printed circuit boards basis of electronic equipment have seen a rapid growth in recent years and played a significant role in modern life. Nowadays, the fact that electronic devices upgrade quickly necessitates a proper management of waste printed circuit boards. Non-destructive desoldering of waste printed circuit boards becomes the first and the most crucial step towards recycling electronic components. Owing to the diversity of materials and components, the separation process is difficult, which results in complex and expensive recovery of precious materials and electronic components from waste printed circuit boards. To cope with this problem, we proposed an innovative approach integrating Theory of Inventive Problem Solving (TRIZ) evolution theory and technology maturity mapping system to forecast the evolution trends of desoldering technology of waste printed circuit boards. This approach can be applied to analyse the technology evolution, as well as desoldering technology evolution, then research and development strategy and evolution laws can be recommended. As an example, the maturity of desoldering technology is analysed with a technology maturity mapping system model. What is more, desoldering methods in different stages are analysed and compared. According to the analysis, the technological evolution trends are predicted to be 'the law of energy conductivity' and 'increasing the degree of idealisation'. And the potential technology and evolutionary state of waste printed circuit boards are predicted, offering reference for future waste printed circuit boards recycling. © The Author(s) 2016.

Direct Desktop Printed-Circuits-on-Paper Flexible Electronics

PubMed Central

Zheng, Yi; He, Zhizhu; Gao, Yunxia; Liu, Jing

2013-01-01

There currently lacks of a way to directly write out electronics, just like printing pictures on paper by an office printer. Here we show a desktop printing of flexible circuits on paper via developing liquid metal ink and related working mechanisms. Through modifying adhesion of the ink, overcoming its high surface tension by dispensing machine and designing a brush like porous pinhead for printing alloy and identifying matched substrate materials among different papers, the slightly oxidized alloy ink was demonstrated to be flexibly printed on coated paper, which could compose various functional electronics and the concept of Printed-Circuits-on-Paper was thus presented. Further, RTV silicone rubber was adopted as isolating inks and packaging material to guarantee the functional stability of the circuit, which suggests an approach for printing 3D hybrid electro-mechanical device. The present work paved the way for a low cost and easygoing method in directly printing paper electronics.

Towards Practical Application of Paper based Printed Circuits: Capillarity Effectively Enhances Conductivity of the Thermoplastic Electrically Conductive Adhesives

PubMed Central

Wu, Haoyi; Chiang, Sum Wai; Lin, Wei; Yang, Cheng; Li, Zhuo; Liu, Jingping; Cui, Xiaoya; Kang, Feiyu; Wong, Ching Ping

2014-01-01

Direct printing nanoparticle-based conductive inks onto paper substrates has encountered difficulties e.g. the nanoparticles are prone to penetrate into the pores of the paper and become partially segmented, and the necessary low-temperature-sintering process is harmful to the dimension-stability of paper. Here we prototyped the paper-based circuit substrate in combination with printed thermoplastic electrically conductive adhesives (ECA), which takes the advantage of the capillarity of paper and thus both the conductivity and mechanical robustness of the printed circuitsweredrastically improved without sintering process. For instance, the electrical resistivity of the ECA specimen on a pulp paper (6 × 10−5Ω·cm, with 50 wt% loading of Ag) was only 14% of that on PET film than that on PET film. This improvement has been found directly related to the sizing degree of paper, in agreement with the effective medium approximation simulation results in this work. The thermoplastic nature also enables excellent mechanical strength of the printed ECA to resist repeated folding. Considering the generality of the process and the wide acceptance of ECA technique in the modern electronic packages, this method may find vast applications in e.g. circuit boards, capacitive touch pads, and radio frequency identification antennas, which have been prototyped in the manuscript. PMID:25182052

Recent Progress in the Development of Printed Thin-Film Transistors and Circuits with High-Resolution Printing Technology.

PubMed

Fukuda, Kenjiro; Someya, Takao

2017-07-01

Printed electronics enable the fabrication of large-scale, low-cost electronic devices and systems, and thus offer significant possibilities in terms of developing new electronics/optics applications in various fields. Almost all electronic applications require information processing using logic circuits. Hence, realizing the high-speed operation of logic circuits is also important for printed devices. This report summarizes recent progress in the development of printed thin-film transistors (TFTs) and integrated circuits in terms of materials, printing technologies, and applications. The first part of this report gives an overview of the development of functional inks such as semiconductors, electrodes, and dielectrics. The second part discusses high-resolution printing technologies and strategies to enable high-resolution patterning. The main focus of this report is on obtaining printed electrodes with high-resolution patterning and the electrical performance of printed TFTs using such printed electrodes. In the final part, some applications of printed electronics are introduced to exemplify their potential. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Printed wiring board system programmer's manual

NASA Technical Reports Server (NTRS)

Brinkerhoff, C. D.

1973-01-01

The printed wiring board system provides automated techniques for the design of printed circuit boards and hybrid circuit boards. The system consists of four programs: (1) the preprocessor program combines user supplied data and pre-defined library data to produce the detailed circuit description data; (2) the placement program assigns circuit components to specific areas of the board in a manner that optimizes the total interconnection length of the circuit; (3) the organizer program assigns pin interconnections to specific board levels and determines the optimal order in which the router program should attempt to layout the paths connecting the pins; and (4) the router program determines the wire paths which are to be used to connect each input pin pair on the circuit board. This document is intended to serve as a programmer's reference manual for the printed wiring board system. A detailed description of the internal logic and flow of the printed wiring board programs is included.

PERSONAL COMPUTER MONITORS: A SCREENING EVALUATION OF VOLATILE ORGANIC EMISSIONS FROM EXISTING PRINTED CIRCUIT BOARD LAMINATES AND POTENTIAL POLLUTION PREVENTION ALTERNATIVES

EPA Science Inventory

The report gives results of a screening evaluation of volatile organic emissions from printed circuit board laminates and potential pollution prevention alternatives. In the evaluation, printed circuit board laminates, without circuitry, commonly found in personal computer (PC) m...

Aluminum heat sink enables power transistors to be mounted integrally with printed circuit board

NASA Technical Reports Server (NTRS)

Seaward, R. C.

1967-01-01

Power transistor is provided with an integral flat plate aluminum heat sink which mounts directly on a printed circuit board containing associated circuitry. Standoff spacers are used to attach the heat sink to the printed circuit board containing the remainder of the circuitry.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fulkerson, Edward; Lanning, Rodney K.; Telford, Steven

A device includes a u-channel shaped member and a printed circuit board including a plurality of capacitors. Each of the plurality of capacitors has a mounting surface mounted to the printed circuit board and an opposing heat transfer surface thermally coupled to the u-channel shaped member. The device also includes an output cable coupled to the printed circuit board and a return cable coupled to the printed circuit board. The device further includes a control transistor disposed inside the u-channel shaped member and a current sensing resistor disposed inside the u-channel shaped member.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitra, Kalyan Yoti, E-mail: kalyan-yoti.mitra@mb.tu-chemnitz.de, E-mail: enrico.sowade@mb.tu-chemnitz.de; Sowade, Enrico, E-mail: kalyan-yoti.mitra@mb.tu-chemnitz.de, E-mail: enrico.sowade@mb.tu-chemnitz.de; Martínez-Domingo, Carme

Inkjet Technology is often mis-believed to be a deposition/patterning technology which is not meant for high fabrication throughput in the field of printed and flexible electronics. In this work, we report on the 1) printing, 2) fabrication yield and 3) characterization of exemplary simple devices e.g. capacitors, organic transistors etc. which are the basic building blocks for logical circuits. For this purpose, printing is performed first with a Proof of concept Inkjet printing system Dimatix Material Printer 2831 (DMP 2831) using 10 pL small print-heads and then with Dimatix Material Printer 3000 (DMP 3000) using 35 pL industrial print-heads (frommore » Fujifilm Dimatix). Printing at DMP 3000 using industrial print-heads (in Sheet-to-sheet) paves the path towards industrialization which can be defined by printing in Roll-to-Roll format using industrial print-heads. This pavement can be termed as 'Bridging Platform'. This transfer to 'Bridging Platform' from 10 pL small print-heads to 35 pL industrial print-heads help the inkjet-printed devices to evolve on the basis of functionality and also in form of up-scaled quantities. The high printed quantities and yield of inkjet-printed devices justify the deposition reliability and potential to print circuits. This reliability is very much desired when it comes to printing of circuits e.g. inverters, ring oscillator and any other planned complex logical circuits which require devices e.g. organic transistors which needs to get connected in different staged levels. Also, the up-scaled inkjet-printed devices are characterized and they reflect a domain under which they can work to their optimal status. This status is much wanted for predicting the real device functionality and integration of them into a planned circuit.« less

Stable Polyurethane Coatings for Electronic Circuits

NASA Technical Reports Server (NTRS)

Morris, D. E.

1983-01-01

Alkane-based polyurethanes resist deterioration while maintaining good dielectric properties. Weight loss after prolonged immersion in hot water far less for alkane-based polyurethanes than for more common ether based polyurethanes, at any given oxygen content. Major uses of polyurethanes are as connector potting materials and conformal coatings for printed circuit boards.

Physically separating printed circuit boards with a resilient, conductive contact

NASA Technical Reports Server (NTRS)

Baker, John D. (Inventor); Montalvo, Alberto (Inventor)

1999-01-01

A multi-board module provides high density electronic packaging in which multiple printed circuit boards are stacked. Electrical power, or signals, are conducted between the boards through a resilient contact. One end of the contact is located at a via in the lower circuit board and soldered to a pad near the via. The top surface of the contact rests against a via of the facing printed circuit board.

PUZZLE - A program for computer-aided design of printed circuit artwork

NASA Technical Reports Server (NTRS)

Harrell, D. A. W.; Zane, R.

1971-01-01

Program assists in solving spacing problems encountered in printed circuit /PC/ design. It is intended to have maximum use for two-sided PC boards carrying integrated circuits, and also aids design of discrete component circuits.

Scalable printed electronics: an organic decoder addressing ferroelectric non-volatile memory.

PubMed

Ng, Tse Nga; Schwartz, David E; Lavery, Leah L; Whiting, Gregory L; Russo, Beverly; Krusor, Brent; Veres, Janos; Bröms, Per; Herlogsson, Lars; Alam, Naveed; Hagel, Olle; Nilsson, Jakob; Karlsson, Christer

2012-01-01

Scalable circuits of organic logic and memory are realized using all-additive printing processes. A 3-bit organic complementary decoder is fabricated and used to read and write non-volatile, rewritable ferroelectric memory. The decoder-memory array is patterned by inkjet and gravure printing on flexible plastics. Simulation models for the organic transistors are developed, enabling circuit designs tolerant of the variations in printed devices. We explain the key design rules in fabrication of complex printed circuits and elucidate the performance requirements of materials and devices for reliable organic digital logic.

High density printed electrical circuit board card connection system

DOEpatents

Baumbaugh, Alan E.

1997-01-01

A zero insertion/extraction force printed circuit board card connection system comprises a cam-operated locking mechanism disposed along an edge portion of the printed circuit board. The extrusions along the circuit board mate with an extrusion fixed to the card cage having a plurality of electrical connectors. The card connection system allows the connectors to be held away from the circuit board during insertion/extraction and provides a constant mating force once the circuit board is positioned. The card connection system provides a simple solution to the need for a greater number of electrical signal connections.

Sorting of large-diameter semiconducting carbon nanotube and printed flexible driving circuit for organic light emitting diode (OLED).

PubMed

Xu, Wenya; Zhao, Jianwen; Qian, Long; Han, Xianying; Wu, Liangzhuan; Wu, Weichen; Song, Minshun; Zhou, Lu; Su, Wenming; Wang, Chao; Nie, Shuhong; Cui, Zheng

2014-01-01

A novel approach was developed to sort a large-diameter semiconducting single-walled carbon nanotube (sc-SWCNT) based on copolyfluorene derivative with high yield. High purity sc-SWCNTs inks were obtained by wrapping arc-discharge SWCNTs with poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) aided by sonication and centrifugation in tetrahydrofuran (THF). The sorted sc-SWCNT inks and nanosilver inks were used to print top-gated thin-film transistors (TFTs) on flexible substrates with an aerosol jet printer. The printed TFTs demonstrated low operating voltage, small hysteresis, high on-state current (up to 10(-3) A), high mobility and on-off ratio. An organic light emitting diode (OLED) driving circuit was constructed based on the printed TFTs, which exhibited high on-off ratio up to 10(4) and output current up to 3.5 × 10(-4) A at V(scan) = -4.5 V and Vdd = 0.8 V. A single OLED was switched on with the driving circuit, showing the potential as backplanes for active matrix OLED applications.

Paper-Based Inkjet-Printed Flexible Electronic Circuits.

PubMed

Wang, Yan; Guo, Hong; Chen, Jin-Ju; Sowade, Enrico; Wang, Yu; Liang, Kun; Marcus, Kyle; Baumann, Reinhard R; Feng, Zhe-Sheng

2016-10-05

Printed flexible electronics have been widely studied for their potential use in various applications. In this paper, a simple, low-cost method of fabricating flexible electronic circuits with high conductivity of 4.0 × 10 7 S·m -1 (about 70% of the conductivity of bulk copper) is demonstrated. Teslin paper substrate is treated with stannous chloride (SnCl 2 ) colloidal solution to reduce the high ink absorption rate, and then the catalyst ink is inkjet-printed on its surface, followed by electroless deposition of copper at low temperature. In spite of the decrease in conductance to some extent, electronic circuits fabricated by this method can maintain function even under various folding angles or after repeated folding. This developed technology has great potential in a variety of applications, such as three-dimensional devices and disposable RFID tags.

Fabrication of Ultra-Thin Printed Organic TFT CMOS Logic Circuits Optimized for Low-Voltage Wearable Sensor Applications.

PubMed

Takeda, Yasunori; Hayasaka, Kazuma; Shiwaku, Rei; Yokosawa, Koji; Shiba, Takeo; Mamada, Masashi; Kumaki, Daisuke; Fukuda, Kenjiro; Tokito, Shizuo

2016-05-09

Ultrathin electronic circuits that can be manufactured by using conventional printing technologies are key elements necessary to realize wearable health sensors and next-generation flexible electronic devices. Due to their low level of power consumption, complementary (CMOS) circuits using both types of semiconductors can be easily employed in wireless devices. Here, we describe ultrathin CMOS logic circuits, for which not only the source/drain electrodes but also the semiconductor layers were printed. Both p-type and n-type organic thin film transistor devices were employed in a D-flip flop circuit in the newly developed stacked structure and exhibited excellent electrical characteristics, including good carrier mobilities of 0.34 and 0.21 cm(2) V(-1) sec(-1), and threshold voltages of nearly 0 V with low operating voltages. These printed organic CMOS D-flip flop circuits exhibit operating frequencies of 75 Hz and demonstrate great potential for flexible and printed electronics technology, particularly for wearable sensor applications with wireless connectivity.

Fabrication of Ultra-Thin Printed Organic TFT CMOS Logic Circuits Optimized for Low-Voltage Wearable Sensor Applications

PubMed Central

Takeda, Yasunori; Hayasaka, Kazuma; Shiwaku, Rei; Yokosawa, Koji; Shiba, Takeo; Mamada, Masashi; Kumaki, Daisuke; Fukuda, Kenjiro; Tokito, Shizuo

2016-01-01

Ultrathin electronic circuits that can be manufactured by using conventional printing technologies are key elements necessary to realize wearable health sensors and next-generation flexible electronic devices. Due to their low level of power consumption, complementary (CMOS) circuits using both types of semiconductors can be easily employed in wireless devices. Here, we describe ultrathin CMOS logic circuits, for which not only the source/drain electrodes but also the semiconductor layers were printed. Both p-type and n-type organic thin film transistor devices were employed in a D-flip flop circuit in the newly developed stacked structure and exhibited excellent electrical characteristics, including good carrier mobilities of 0.34 and 0.21 cm2 V−1 sec−1, and threshold voltages of nearly 0 V with low operating voltages. These printed organic CMOS D-flip flop circuits exhibit operating frequencies of 75 Hz and demonstrate great potential for flexible and printed electronics technology, particularly for wearable sensor applications with wireless connectivity. PMID:27157914

Fate of bromine in pyrolysis of printed circuit board wastes.

PubMed

Chien, Y C; Wang, H P; Lin, K S; Huang, Y J; Yang, Y W

2000-02-01

Behavior of Br in pyrolysis of the printed circuit board waste with valuable copper and oil recycling has been studied in the present work. Experimentally, pyrolysis of the printed circuit board waste generated approximately 40.6% of oils, 24.9% of noncondensible gases and 34.5% of solid residues that enriched in copper (90-95%). The cuts of the oils produced from pyrolysis of the printed circuit board waste into weighted boiling fraction were primarily light naphtha and heavy gas oil. Approximately 72.3% of total Br in the printed circuit board waste were found in product gas mainly as HBr and bromobenzene. However, by extended X-ray absorption fine structural (EXAFS) spectroscopy, Cu-O and Cu-(O)-Cu species with bond distance of 1.87 and 2.95 A, respectively, were observed in the solid residues. Essentially, no Cu-Br species was found.

A screen-printed circular-type paper-based glucose/O2 biofuel cell

NASA Astrophysics Data System (ADS)

Shitanda, Isao; Nohara, Saki; Hoshi, Yoshinao; Itagaki, Masayuki; Tsujimura, Seiya

2017-08-01

The printable paper-based enzymatic biofuel cell (PBFC) to directly power small devices is an important objective for realizing cost-effective and disposable energy harvesting devices. In the present study, a screen-printed circular-type PBFC, composed of a series of 5 individual cells, was constructed. The PBFC exhibited the open circuit potential of 2.65 V and maximum power of 350 μW at 1.55 V, which were sufficient to illuminate an LED without requiring a booster circuit. The output voltage of this PBFC can also be easily adjusted as required.

Behaviour of one-step spray-coated carbon nanotube supercapacitor in ambient light harvester circuit with printed organic solar cell and electrochromic display.

PubMed

Tuukkanen, Sampo; Välimäki, Marja; Lehtimäki, Suvi; Vuorinen, Tiina; Lupo, Donald

2016-03-09

A printed energy harvesting and storage circuit powered by ambient office lighting and its use to power a printed display is reported. The autonomous device is composed of three printed electronic components: an organic photovoltaic module, a carbon-nanotubes-only supercapacitor and an electrochromic display element. Components are fabricated from safe and environmentally friendly materials, and have been fabricated using solution processing methods, which translate into low-cost and high-throughput manufacturing. A supercapacitor made of spray-coated carbon nanotube based ink and aqueous NaCl electrolyte was charged using a printed organic photovoltaic module exposed to office lighting conditions. The supercapacitor charging rate, self-discharge rate and display operation were studied in detail. The supercapacitor self-discharge rate was found to depend on the charging rate. The fully charged supercapacitor was used as a power source to run the electrochromic display over 50 times.

Scalable printed electronics: an organic decoder addressing ferroelectric non-volatile memory

PubMed Central

Ng, Tse Nga; Schwartz, David E.; Lavery, Leah L.; Whiting, Gregory L.; Russo, Beverly; Krusor, Brent; Veres, Janos; Bröms, Per; Herlogsson, Lars; Alam, Naveed; Hagel, Olle; Nilsson, Jakob; Karlsson, Christer

2012-01-01

Scalable circuits of organic logic and memory are realized using all-additive printing processes. A 3-bit organic complementary decoder is fabricated and used to read and write non-volatile, rewritable ferroelectric memory. The decoder-memory array is patterned by inkjet and gravure printing on flexible plastics. Simulation models for the organic transistors are developed, enabling circuit designs tolerant of the variations in printed devices. We explain the key design rules in fabrication of complex printed circuits and elucidate the performance requirements of materials and devices for reliable organic digital logic. PMID:22900143

Aerosol-jet-printed, 1 volt H-bridge drive circuit on plastic with integrated electrochromic pixel.

PubMed

Ha, Mingjing; Zhang, Wei; Braga, Daniele; Renn, Michael J; Kim, Chris H; Frisbie, C Daniel

2013-12-26

In this report, we demonstrate a printed, flexible, and low-voltage circuit that successfully drives a polymer electrochromic (EC) pixel as large as 4 mm(2) that is printed on the same substrate. All of the key components of the drive circuitry, namely, resistors, capacitors, and transistors, were aerosol-jet-printed onto a plastic foil; metallic electrodes and interconnects were the only components prepatterned on the plastic by conventional photolithography. The large milliampere drive currents necessary to switch a 4 mm(2) EC pixel were controlled by printed electrolyte-gated transistors (EGTs) that incorporate printable ion gels for the gate insulator layers and poly(3-hexylthiophene) for the semiconductor channels. Upon application of a 1 V input pulse, the circuit switches the printed EC pixel ON (red) and OFF (blue) two times in approximately 4 s. The performance of the circuit and the behavior of the individual resistors, capacitors, EGTs, and the EC pixel are analyzed as functions of the printing parameters and operating conditions.

Stretchable electronics based on Ag-PDMS composites

PubMed Central

Larmagnac, Alexandre; Eggenberger, Samuel; Janossy, Hanna; Vörös, Janos

2014-01-01

Patterned structures of flexible, stretchable, electrically conductive materials on soft substrates could lead to novel electronic devices with unique mechanical properties allowing them to bend, fold, stretch or conform to their environment. For the last decade, research on improving the stretchability of circuits on elastomeric substrates has made significant progresses but designing printed circuit assemblies on elastomers remains challenging. Here we present a simple, cost-effective, cleanroom-free process to produce large scale soft electronic hardware where standard surface-mounted electrical components were directly bonded onto all-elastomeric printed circuit boards, or soft PCBs. Ag-PDMS tracks were stencil printed onto a PDMS substrate and soft PCBs were made by bonding the top and bottom layers together and filling punched holes with Ag-PDMS to create vias. Silver epoxy was used to bond commercial electrical components and no mechanical failure was observed after hundreds of stretching cycles. We also demonstrate the fabrication of a stretchable clock generator. PMID:25434843

Thumbnail Sketches: The Chemistry of Printed Circuit Substrates: Some of the Latest Developments.

ERIC Educational Resources Information Center

Freeman, James H.

1984-01-01

Discusses some of the latest developments in the chemistry of printed circuit substrates. Topics considered include soldering, dicy (a catalyst), Kevlar (an aramid polymer fiber), maleimide copolymers, and flexible circuits. (JN)

Packaging system with cleaning channel and method of making the same

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fang, Lu

A packaging structure and method for surface mount integrated circuits reduces electrochemical migration (ECM) problems by including one or more cleaning channels to effectively and efficiently remove flux residue that may otherwise remain lodged in gaps between the surface mount package and the printed circuit board. A cleaning channel may be formed along a bottom surface of the surface mount package (i.e., the surface facing the printed circuit board), or along a portion of a top surface of the printed circuit board. In either case, the inclusion of a cleaning channel enlarges the gap between the bottom surface of themore » surface mount package and the printed circuit board and creates a path for contaminants to be flushed out during a cleaning process.« less

Flexible composite film for printed circuit board

NASA Technical Reports Server (NTRS)

Yabe, K.; Asakura, M.; Tanaka, H.; Soda, A.

1982-01-01

A flexible printed circuit for a printed circuit board in which layers of reaction product composed of a combination of phenoxy resin - polyisocyanate - brominated epoxy resin, and in which the equivalent ratio of those functional groups is hydroxyl group: isocyanate group: epoxy group - 1 : 0.2 to 2 : 0.5 to 3 are laminated on at least one side of saturated polyester film is discussed.

Design of a CMOS readout circuit on ultra-thin flexible silicon chip for printed strain gauges

NASA Astrophysics Data System (ADS)

Elsobky, Mourad; Mahsereci, Yigit; Keck, Jürgen; Richter, Harald; Burghartz, Joachim N.

2017-09-01

Flexible electronics represents an emerging technology with features enabling several new applications such as wearable electronics and bendable displays. Precise and high-performance sensors readout chips are crucial for high quality flexible electronic products. In this work, the design of a CMOS readout circuit for an array of printed strain gauges is presented. The ultra-thin readout chip and the printed sensors are combined on a thin Benzocyclobutene/Polyimide (BCB/PI) substrate to form a Hybrid System-in-Foil (HySiF), which is used as an electronic skin for robotic applications. Each strain gauge utilizes a Wheatstone bridge circuit, where four Aerosol Jet® printed meander-shaped resistors form a full-bridge topology. The readout chip amplifies the output voltage difference (about 5 mV full-scale swing) of the strain gauge. One challenge during the sensor interface circuit design is to compensate for the relatively large dc offset (about 30 mV at 1 mA) in the bridge output voltage so that the amplified signal span matches the input range of an analog-to-digital converter (ADC). The circuit design uses the 0. 5 µm mixed-signal GATEFORESTTM technology. In order to achieve the mechanical flexibility, the chip fabrication is based on either back thinned wafers or the ChipFilmTM technology, which enables the manufacturing of silicon chips with a thickness of about 20 µm. The implemented readout chip uses a supply of 5 V and includes a 5-bit digital-to-analog converter (DAC), a differential difference amplifier (DDA), and a 10-bit successive approximation register (SAR) ADC. The circuit is simulated across process, supply and temperature corners and the simulation results indicate excellent performance in terms of circuit stability and linearity.

40 CFR 413.80 - Applicability: Description of the printed circuit board subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Applicability: Description of the printed circuit board subcategory. 413.80 Section 413.80 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ELECTROPLATING POINT SOURCE CATEGORY Printed...

Natural printed silk substrate circuit fabricated via surface modification using one step thermal transfer and reduction graphene oxide

NASA Astrophysics Data System (ADS)

Cao, Jiliang; Huang, Zhan; Wang, Chaoxia

2018-05-01

Graphene conductive silk substrate is a preferred material because of its biocompatibility, flexibility and comfort. A flexible natural printed silk substrate circuit was fabricated by one step transfer of graphene oxide (GO) paste from transfer paper to the surface of silk fabric and reduction of the GO to reduced graphene oxide (RGO) using a simple hot press treatment. The GO paste was obtained through ultrasonic stirring exfoliation under low temperature, and presented excellent printing rheological properties at high concentration. The silk fabric was obtained a surface electric resistance as low as 12.15 KΩ cm-1, in the concentration of GO 50 g L-1 and hot press at 220 °C for 120 s. Though the whiteness and strength decreased with the increasing of hot press temperature and time slowly, the electric conductivity of RGO surface modification silk substrate improved obviously. The surface electric resistance of RGO/silk fabrics increased from 12.15 KΩ cm-1 to 18.05 KΩ cm-1, 28.54 KΩ cm-1 and 32.53 KΩ cm-1 after 10, 20 and 30 washing cycles, respectively. The results showed that the printed silk substrate circuit has excellent washability. This process requires no chemical reductant, and the reduction efficiency and reduction degree of GO is high. This time-effective and environmentally-friendly one step thermal transfer and reduction graphene oxide onto natural silk substrate method can be easily used to production of reduced graphene oxide (RGO) based flexible printed circuit.

Assembling surface mounted components on ink-jet printed double sided paper circuit board.

PubMed

Andersson, Henrik A; Manuilskiy, Anatoliy; Haller, Stefan; Hummelgård, Magnus; Sidén, Johan; Hummelgård, Christine; Olin, Håkan; Nilsson, Hans-Erik

2014-03-07

Printed electronics is a rapidly developing field where many components can already be manufactured on flexible substrates by printing or by other high speed manufacturing methods. However, the functionality of even the most inexpensive microcontroller or other integrated circuit is, at the present time and for the foreseeable future, out of reach by means of fully printed components. Therefore, it is of interest to investigate hybrid printed electronics, where regular electrical components are mounted on flexible substrates to achieve high functionality at a low cost. Moreover, the use of paper as a substrate for printed electronics is of growing interest because it is an environmentally friendly and renewable material and is, additionally, the main material used for many packages in which electronics functionalities could be integrated. One of the challenges for such hybrid printed electronics is the mounting of the components and the interconnection between layers on flexible substrates with printed conductive tracks that should provide as low a resistance as possible while still being able to be used in a high speed manufacturing process. In this article, several conductive adhesives are evaluated as well as soldering for mounting surface mounted components on a paper circuit board with ink-jet printed tracks and, in addition, a double sided Arduino compatible circuit board is manufactured and programmed.

Behaviour of one-step spray-coated carbon nanotube supercapacitor in ambient light harvester circuit with printed organic solar cell and electrochromic display

PubMed Central

Tuukkanen, Sampo; Välimäki, Marja; Lehtimäki, Suvi; Vuorinen, Tiina; Lupo, Donald

2016-01-01

A printed energy harvesting and storage circuit powered by ambient office lighting and its use to power a printed display is reported. The autonomous device is composed of three printed electronic components: an organic photovoltaic module, a carbon-nanotubes-only supercapacitor and an electrochromic display element. Components are fabricated from safe and environmentally friendly materials, and have been fabricated using solution processing methods, which translate into low-cost and high-throughput manufacturing. A supercapacitor made of spray-coated carbon nanotube based ink and aqueous NaCl electrolyte was charged using a printed organic photovoltaic module exposed to office lighting conditions. The supercapacitor charging rate, self-discharge rate and display operation were studied in detail. The supercapacitor self-discharge rate was found to depend on the charging rate. The fully charged supercapacitor was used as a power source to run the electrochromic display over 50 times. PMID:26957019

Thin-film copper indium gallium selenide solar cell based on low-temperature all-printing process.

PubMed

Singh, Manjeet; Jiu, Jinting; Sugahara, Tohru; Suganuma, Katsuaki

2014-09-24

In the solar cell field, development of simple, low-cost, and low-temperature fabrication processes has become an important trend for energy-saving and environmental issues. Copper indium gallium selenide (CIGS) solar cells have attracted much attention due to the high absorption coefficient, tunable band gap energy, and high efficiency. However, vacuum and high-temperature processing in fabrication of solar cells have limited the applications. There is a strong need to develop simple and scalable methods. In this work, a CIGS solar cell based on all printing steps and low-temperature annealing is developed. CIGS absorber thin film is deposited by using dodecylamine-stabilized CIGS nanoparticle ink followed by printing buffer layer. Silver nanowire (AgNW) ink and sol-gel-derived ZnO precursor solution are used to prepare a highly conductive window layer ZnO/[AgNW/ZnO] electrode with a printing method that achieves 16 Ω/sq sheet resistance and 94% transparency. A CIGS solar cell based on all printing processes exhibits efficiency of 1.6% with open circuit voltage of 0.48 V, short circuit current density of 9.7 mA/cm(2), and fill factor of 0.34 for 200 nm thick CIGS film, fabricated under ambient conditions and annealed at 250 °C.

Toward printed integrated circuits based on unipolar or ambipolar polymer semiconductors.

PubMed

Baeg, Kang-Jun; Caironi, Mario; Noh, Yong-Young

2013-08-21

For at least the past ten years printed electronics has promised to revolutionize our daily life by making cost-effective electronic circuits and sensors available through mass production techniques, for their ubiquitous applications in wearable components, rollable and conformable devices, and point-of-care applications. While passive components, such as conductors, resistors and capacitors, had already been fabricated by printing techniques at industrial scale, printing processes have been struggling to meet the requirements for mass-produced electronics and optoelectronics applications despite their great potential. In the case of logic integrated circuits (ICs), which constitute the focus of this Progress Report, the main limitations have been represented by the need of suitable functional inks, mainly high-mobility printable semiconductors and low sintering temperature conducting inks, and evoluted printing tools capable of higher resolution, registration and uniformity than needed in the conventional graphic arts printing sector. Solution-processable polymeric semiconductors are the best candidates to fulfill the requirements for printed logic ICs on flexible substrates, due to their superior processability, ease of tuning of their rheology parameters, and mechanical properties. One of the strongest limitations has been mainly represented by the low charge carrier mobility (μ) achievable with polymeric, organic field-effect transistors (OFETs). However, recently unprecedented values of μ ∼ 10 cm(2) /Vs have been achieved with solution-processed polymer based OFETs, a value competing with mobilities reported in organic single-crystals and exceeding the performances enabled by amorphous silicon (a-Si). Interestingly these values were achieved thanks to the design and synthesis of donor-acceptor copolymers, showing limited degree of order when processed in thin films and therefore fostering further studies on the reason leading to such improved charge transport properties. Among this class of materials, various polymers can show well balanced electrons and holes mobility, therefore being indicated as ambipolar semiconductors, good environmental stability, and a small band-gap, which simplifies the tuning of charge injection. This opened up the possibility of taking advantage of the superior performances offered by complementary "CMOS-like" logic for the design of digital ICs, easing the scaling down of critical geometrical features, and achieving higher complexity from robust single gates (e.g., inverters) and test circuits (e.g., ring oscillators) to more complete circuits. Here, we review the recent progress in the development of printed ICs based on polymeric semiconductors suitable for large-volume micro- and nano-electronics applications. Particular attention is paid to the strategies proposed in the literature to design and synthesize high mobility polymers and to develop suitable printing tools and techniques to allow for improved patterning capability required for the down-scaling of devices in order to achieve the operation frequencies needed for applications, such as flexible radio-frequency identification (RFID) tags, near-field communication (NFC) devices, ambient electronics, and portable flexible displays. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Computer circuit card puller

NASA Technical Reports Server (NTRS)

Sawyer, R. V.; Szuwalski, B. (Inventor)

1981-01-01

The invention generally relates to hand tools, and more particularly to an improved device for facilitating removal of printed circuit cards from a card rack characterized by longitudinal side rails arranged in a mutually spaced parallelism and a plurality of printed circuit cards extended between the rails of the rack.

Degradation of organic pollutants by Ag, Cu and Sn doped waste non-metallic printed circuit boards.

PubMed

Ramaswamy, Kadari; Radha, Velchuri; Malathi, M; Vithal, Muga; Munirathnam, Nagegownivari R

2017-02-01

The disposal and reuse of waste printed circuit boards have been the major global concerns. Printed circuit boards, a form of Electronic waste (hereafter e-waste), have been chemically processed, doped with Ag + , Cu 2+ and Sn 2+ , and used as visible light photocatalysts against the degradation of methylene blue and methyl violet. The elemental analyses of pristine and metal doped printed circuit board were obtained using energy dispersive X-ray fluorescence (EDXRF) spectra and inductively coupled plasma optical emission spectroscopy (ICP-OES). The morphology of parent and doped printed circuit board was obtained from scanning electron microscopy (SEM) measurements. The photocatalytic activity of parent and metal doped samples was carried out for the decomposition of organic pollutants, methylene blue and methyl violet, under visible light irradiation. Metal doped waste printed circuit boards (WPCBs) have shown higher photocatalytic activity against the degradation of methyl violet and methylene blue under visible light irradiation. Scavenger experiments were performed to identify the reactive intermediates responsible for the degradation of methylene blue and methyl violet. The reactive species responsible for the degradation of MV and MB were found to be holes and hydroxyl radicals. A possible mechanism of degradation of methylene blue and methyl violet is given. The stability and reusability of the catalysts are also investigated. Copyright © 2016. Published by Elsevier Ltd.

[Flexible print circuit technology application in biomedical engineering].

PubMed

Jiang, Lihua; Cao, Yi; Zheng, Xiaolin

2013-06-01

Flexible print circuit (FPC) technology has been widely applied in variety of electric circuits with high precision due to its advantages, such as low-cost, high specific fabrication ability, and good flexibility, etc. Recently, this technology has also been used in biomedical engineering, especially in the development of microfluidic chip and microelectrode array. The high specific fabrication can help making microelectrode and other micro-structure equipment. And good flexibility allows the micro devices based on FPC technique to be easily packaged with other parts. In addition, it also reduces the damage of microelectrodes to the tissue. In this paper, the application of FPC technology in biomedical engineering is introduced. Moreover, the important parameters of FPC technique and the development trend of prosperous applications is also discussed.

Feasibility Test of a Liquid Film Thickness Sensor on a Flexible Printed Circuit Board Using a Three-Electrode Conductance Method

PubMed Central

Lee, Kyu Byung; Kim, Jong Rok; Park, Goon Cherl; Cho, Hyoung Kyu

2016-01-01

Liquid film thickness measurements under temperature-varying conditions in a two-phase flow are of great importance to refining our understanding of two-phase flows. In order to overcome the limitations of the conventional electrical means of measuring the thickness of a liquid film, this study proposes a three-electrode conductance method, with the device fabricated on a flexible printed circuit board (FPCB). The three-electrode conductance method offers the advantage of applicability under conditions with varying temperatures in principle, while the FPCB has the advantage of usability on curved surfaces and in relatively high-temperature conditions in comparison with sensors based on a printed circuit board (PCB). Two types of prototype sensors were fabricated on an FPCB and the feasibility of both was confirmed in a calibration test conducted at different temperatures. With the calibrated sensor, liquid film thickness measurements were conducted via a falling liquid film flow experiment, and the working performance was tested. PMID:28036000

All-Printed Flexible and Stretchable Electronics.

PubMed

Mohammed, Mohammed G; Kramer, Rebecca

2017-05-01

A fully automated additive manufacturing process that produces all-printed flexible and stretchable electronics is demonstrated. The printing process combines soft silicone elastomer printing and liquid metal processing on a single high-precision 3D stage. The platform is capable of fabricating extremely complex conductive circuits, strain and pressure sensors, stretchable wires, and wearable circuits with high yield and repeatability. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Analytical Study on Thermal and Mechanical Design of Printed Circuit Heat Exchanger

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Su-Jong; Sabharwall, Piyush; Kim, Eung-Soo

2013-09-01

The analytical methodologies for the thermal design, mechanical design and cost estimation of printed circuit heat exchanger are presented in this study. In this study, three flow arrangements of parallel flow, countercurrent flow and crossflow are taken into account. For each flow arrangement, the analytical solution of temperature profile of heat exchanger is introduced. The size and cost of printed circuit heat exchangers for advanced small modular reactors, which employ various coolants such as sodium, molten salts, helium, and water, are also presented.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, T.; Hu, M.; Guo, Q.

Here we report a study of printing of electronics using an office use laser printer. The proposed method eliminates those critical disadvantages of solvent-based printing techniques by taking the advantages of electroless deposition and laser printing. The synthesized toner acts as a catalyst for the electroless copper deposition as well as an adhesion-promoting buffer layer between the substrate and deposited copper. The easy metallization of printed patterns and strong metal-substrate adhesion make it an especially effective method for massive production of flexible printed circuits. The proposed process is a high throughput, low cost, efficient, and environmentally benign method for flexiblemore » electronics manufacturing.« less

Printed dose-recording tag based on organic complementary circuits and ferroelectric nonvolatile memories

PubMed Central

Nga Ng, Tse; Schwartz, David E.; Mei, Ping; Krusor, Brent; Kor, Sivkheng; Veres, Janos; Bröms, Per; Eriksson, Torbjörn; Wang, Yong; Hagel, Olle; Karlsson, Christer

2015-01-01

We have demonstrated a printed electronic tag that monitors time-integrated sensor signals and writes to nonvolatile memories for later readout. The tag is additively fabricated on flexible plastic foil and comprises a thermistor divider, complementary organic circuits, and two nonvolatile memory cells. With a supply voltage below 30 V, the threshold temperatures can be tuned between 0 °C and 80 °C. The time-temperature dose measurement is calibrated for minute-scale integration. The two memory bits are sequentially written in a thermometer code to provide an accumulated dose record. PMID:26307438

Front-Side Microstrip Line Feeding a Raised Antenna Patch

NASA Technical Reports Server (NTRS)

Hodges, Richard; Hoppe, Daniel

2005-01-01

An improved design concept for a printed-circuit patch antenna and the transmission line that feeds the patch calls for (1) a microstrip transmission line on the front (radiative) side of a printed-circuit board based on a thin, high-permittivity dielectric substrate; (2) using the conductor covering the back side of the circuit board as a common ground plane for both the microstrip line and the antenna patch; (3) supporting the antenna patch in front of the circuit board on a much thicker, lower-permittivity dielectric spacer layer; and (4) connecting the microstrip transmission line to the patch by use of a thin wire or narrow ribbon that extends through the thickness of the spacer and is oriented perpendicularly to the circuit-board plane. The thickness of the substrate is typically chosen so that a microstrip transmission line of practical width has an impedance between 50 and 100 ohms. The advantages of this design concept are best understood in the context of the disadvantages of prior design concepts, as explained

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hadi, Pejman; Ning, Chao; Ouyang, Weiyi

Highlights: • Environmental impacts of electronic waste and specifically waste printed circuit boards. • Review of the recycling techniques of waste printed circuit boards. • Advantages of physico-mechanical recycling techniques over chemical methods. • Utilization of nonmetallic fraction of waste printed circuit boards as modifier/filler. • Recent advances in the use of nonmetallic fraction of waste printed circuit boards as precursor. - Abstract: Electronic waste, including printed circuit boards, is growing at an alarming rate due to the accelerated technological progress and the shorter lifespan of the electronic equipment. In the past decades, due to the lack of proper economicmore » and environmentally-benign recycling technologies, a major fraction of e-waste generated was either destined to landfills or incinerated with the sole intention of its disposal disregarding the toxic nature of this waste. Recently, with the increasing public awareness over their environment and health issues and with the enaction of more stringent regulations, environmentally-benign recycling has been driven to be an alternative option partially replacing the traditional eco-unfriendly disposal methods. One of the most favorable green technologies has been the mechanical separation of the metallic and nonmetallic fraction of the waste printed circuit boards. Although metallic fraction, as the most profitable component, is used to generate the revenue of the separation process, the nonmetallic fraction (NMF) has been left isolated. Herein, the recent developments in the application of NMF have been comprehensively reviewed and an eco-friendly emerging usage of NMF as a value-added material for sustainable remediation has been introduced.« less

Laser Integration on Silicon Photonic Circuits Through Transfer Printing

DTIC Science & Technology

2017-03-10

AFRL-AFOSR-UK-TR-2017-0019 Laser integration on silicon photonic circuits through transfer printing Gunther Roelkens UNIVERSITEIT GENT VZW Final...TYPE Final 3. DATES COVERED (From - To) 15 Sep 2015 to 14 Sep 2016 4. TITLE AND SUBTITLE Laser integration on silicon photonic circuits through...parallel integration of III-V lasers on silicon photonic integrated circuits. The report discusses the technological process that has been developed as

High-performance all-printed amorphous oxide FETs and logics with electronically compatible electrode/ channel interface.

PubMed

Sharma, Bhupendra Kumar; Stoesser, Anna; Mondal, Sandeep Kumar; Garlapati, Suresh K; Fawey, Mohammed H; Chakravadhanula, Venkata Sai Kiran; Kruk, Robert; Hahn, Horst; Dasgupta, Subho

2018-06-12

Oxide semiconductors typically show superior device performance compared to amorphous silicon or organic counterparts, especially, when they are physical vapor deposited. However, it is not easy to reproduce identical device characteristics when the oxide field-effect transistors (FETs) are solution-processed/ printed; the level of complexity further intensifies with the need to print the passive elements as well. Here, we developed a protocol for designing the most electronically compatible electrode/ channel interface based on the judicious material selection. Exploiting this newly developed fabrication schemes, we are now able to demonstrate high-performance all-printed FETs and logic circuits using amorphous indium-gallium-zinc oxide (a-IGZO) semiconductor, indium tin oxide (ITO) as electrodes and composite solid polymer electrolyte as the gate insulator. Interestingly, all-printed FETs demonstrate an optimal electrical performance in terms of threshold voltages and device mobility and may very well be compared with devices fabricated using sputtered ITO electrodes. This observation originates from the selection of electrode/ channel materials from the same transparent semiconductor oxide family, resulting in the formation of In-Sn-Zn-O (ITZO) based diffused a-IGZO/ ITO interface that controls doping density while ensuring high electrical performance. Compressive spectroscopic studies reveal that Sn doping mediated excellent band alignment of IGZO with ITO electrodes is responsible for the excellent device performance observed. All-printed n-MOS based logic circuits have also been demonstrated towards new-generation portable electronics.

Soft-Matter Printed Circuit Board with UV Laser Micropatterning.

PubMed

Lu, Tong; Markvicka, Eric J; Jin, Yichu; Majidi, Carmel

2017-07-05

When encapsulated in elastomer, micropatterned traces of Ga-based liquid metal (LM) can function as elastically deformable circuit wiring that provides mechanically robust electrical connectivity between solid-state elements (e.g., transistors, processors, and sensor nodes). However, LM-microelectronics integration is currently limited by challenges in rapid fabrication of LM circuits and the creation of vias between circuit terminals and the I/O pins of packaged electronics. In this study, we address both with a unique layup for soft-matter electronics in which traces of liquid-phase Ga-In eutectic (EGaIn) are patterned with UV laser micromachining (UVLM). The terminals of the elastomer-sealed LM circuit connect to the surface mounted chips through vertically aligned columns of EGaIn-coated Ag-Fe 2 O 3 microparticles that are embedded within an interfacial elastomer layer. The processing technique is compatible with conventional UVLM printed circuit board (PCB) prototyping and exploits the photophysical ablation of EGaIn on an elastomer substrate. Potential applications to wearable computing and biosensing are demonstrated with functional implementations in which soft-matter PCBs are populated with surface-mounted microelectronics.

Agent-based services for B2B electronic commerce

NASA Astrophysics Data System (ADS)

Fong, Elizabeth; Ivezic, Nenad; Rhodes, Tom; Peng, Yun

2000-12-01

The potential of agent-based systems has not been realized yet, in part, because of the lack of understanding of how the agent technology supports industrial needs and emerging standards. The area of business-to-business electronic commerce (b2b e-commerce) is one of the most rapidly developing sectors of industry with huge impact on manufacturing practices. In this paper, we investigate the current state of agent technology and the feasibility of applying agent-based computing to b2b e-commerce in the circuit board manufacturing sector. We identify critical tasks and opportunities in the b2b e-commerce area where agent-based services can best be deployed. We describe an implemented agent-based prototype system to facilitate the bidding process for printed circuit board manufacturing and assembly. These activities are taking place within the Internet Commerce for Manufacturing (ICM) project, the NIST- sponsored project working with industry to create an environment where small manufacturers of mechanical and electronic components may participate competitively in virtual enterprises that manufacture printed circuit assemblies.

Bioextraction of Copper from Printed Circuit Boards: Influence of Initial Concentration of Ferrous Iron

NASA Astrophysics Data System (ADS)

Yamane, Luciana Harue; Espinosa, Denise Crocce Romano; Tenório, Jorge Alberto Soares

Printed circuit boards are found in all electric and electronic equipment and are particularly problematic to recycle because of the heterogeneous mix of organic material, metals, and fiberglass. Additionally, printed circuit boards can be considered a secondary source of copper and bacterial leaching can be applied to copper recovery. This study investigated the influence of initial concentration of ferrous iron on bacterial leaching to recover copper from printed circuit boards using Acidithiobacillus ferrooxidans-LR. Printed circuit boards from computers were comminuted using a hammer mill. The powder obtained was magnetically separated and the non magnetic material used in this study. A shake flask study was carried out on the non magnetic material using a rotary shaker at 30°C, 170 rpm and different initial concentrations of ferrous iron (gL-1): 6.75; 13.57 and 16.97. Abiotic controls were also run in parallel. The monitored parameters were pH, Eh, ferrous iron concentration and copper extraction (spectroscopy of atomic absorption). The results showed that using initial concentration of ferrous iron of 6.75gL-1 were extracted 99% of copper by bacterial leaching.

Design of a smart ECG garment based on conductive textile electrode and flexible printed circuit board.

PubMed

Cai, Zhipeng; Luo, Kan; Liu, Chengyu; Li, Jianqing

2017-08-09

A smart electrocardiogram (ECG) garment system was designed for continuous, non-invasive and comfortable ECG monitoring, which mainly consists of four components: Conductive textile electrode, garment, flexible printed circuit board (FPCB)-based ECG processing module and android application program. Conductive textile electrode and FPCB-based ECG processing module (6.8 g, 55 mm × 53 mm × 5 mm) are identified as two key techniques to improve the system's comfort and flexibility. Preliminary experimental results verified that the textile electrodes with circle shape, 40 mm size in diameter, and 5 mm thickness sponge are best suited for the long-term ECG monitoring application. The tests on the whole system confirmed that the designed smart garment can obtain long-term ECG recordings with high signal quality.

HBCU/MI: 3D Formable RF Materials and Devices

DTIC Science & Technology

2016-08-01

SECURITY CLASSIFICATION OF: The aim of this project was to explore 3D printing for RF/microwave circuits and devices. The research produced several... 3D printed microwave filters, a 3D wifi radio circuit, and new materials for 3D printed electromagnetic devices. The research demonstrates that 3D ...journals: Final Report: HBCU/MI: 3D Formable RF Materials and Devices Report Title The aim of this project was to explore 3D printing for RF/microwave

Recycling-oriented characterization of plastic frames and printed circuit boards from mobile phones by electronic and chemical imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palmieri, Roberta; Bonifazi, Giuseppe; Serranti, Silvia, E-mail: silvia.serranti@uniroma1.it

Highlights: • A recycling oriented characterization of end-of-life mobile phones was carried out. • Characterization was developed in a zero-waste-perspective, aiming to recover all the mobile phone materials. • Plastic frames and printed circuit boards were analyzed by electronic and chemical imaging. • Suitable milling/classification strategies were set up to define specialized-pre-concentrated-streams. • The proposed approach can improve the recovery of polymers, base/precious metals, rare earths and critical raw materials. - Abstract: This study characterizes the composition of plastic frames and printed circuit boards from end-of-life mobile phones. This knowledge may help define an optimal processing strategy for using thesemore » items as potential raw materials. Correct handling of such a waste is essential for its further “sustainable” recovery, especially to maximize the extraction of base, rare and precious metals, minimizing the environmental impact of the entire process chain. A combination of electronic and chemical imaging techniques was thus examined, applied and critically evaluated in order to optimize the processing, through the identification and the topological assessment of the materials of interest and their quantitative distribution. To reach this goal, end-of-life mobile phone derived wastes have been systematically characterized adopting both “traditional” (e.g. scanning electronic microscopy combined with microanalysis and Raman spectroscopy) and innovative (e.g. hyperspectral imaging in short wave infrared field) techniques, with reference to frames and printed circuit boards. Results showed as the combination of both the approaches (i.e. traditional and classical) could dramatically improve recycling strategies set up, as well as final products recovery.« less

TSCA Chemical Data Reporting Fact Sheet: Byproducts Reporting for the Printed Circuit Board Industry

EPA Pesticide Factsheets

This fact sheet provides information on existing Chemical Data Reporting (CDR) rule requirements related to byproducts reporting by persons who manufacture printed circuit boards and may be subject to CDR.

Inkjet deposited circuit components

NASA Astrophysics Data System (ADS)

Bidoki, S. M.; Nouri, J.; Heidari, A. A.

2010-05-01

All-printed electronics as a means of achieving ultra-low-cost electronic circuits has attracted great interest in recent years. Inkjet printing is one of the most promising techniques by which the circuit components can be ultimately drawn (i.e. printed) onto the substrate in one step. Here, the inkjet printing technique was used to chemically deposit silver nanoparticles (10-200 nm) simply by ejection of silver nitrate and reducing solutions onto different substrates such as paper, PET plastic film and textile fabrics. The silver patterns were tested for their functionality to work as circuit components like conductor, resistor, capacitor and inductor. Different levels of conductivity were achieved simply by changing the printing sequence, inks ratio and concentration. The highest level of conductivity achieved by an office thermal inkjet printer (300 dpi) was 5.54 × 105 S m-1 on paper. Inkjet deposited capacitors could exhibit a capacitance of more than 1.5 nF (parallel plate 45 × 45 mm2) and induction coils displayed an inductance of around 400 µH (planar coil 10 cm in diameter). Comparison of electronic performance of inkjet deposited components to the performance of conventionally etched items makes the technique highly promising for fabricating different printed electronic devices.

Low-Cost Manufacturing of Bioresorbable Conductors by Evaporation-Condensation-Mediated Laser Printing and Sintering of Zn Nanoparticles.

PubMed

Shou, Wan; Mahajan, Bikram K; Ludwig, Brandon; Yu, Xiaowei; Staggs, Joshua; Huang, Xian; Pan, Heng

2017-07-01

Currently, bioresorbable electronic devices are predominantly fabricated by complex and expensive vacuum-based integrated circuit (IC) processes. Here, a low-cost manufacturing approach for bioresorbable conductors on bioresorbable polymer substrates by evaporation-condensation-mediated laser printing and sintering of Zn nanoparticle is reported. Laser sintering of Zn nanoparticles has been technically difficult due to the surface oxide on nanoparticles. To circumvent the surface oxide, a novel approach is discovered to print and sinter Zn nanoparticle facilitated by evaporation-condensation in confined domains. The printing process can be performed on low-temperature substrates in ambient environment allowing easy integration on a roll-to-roll platform for economical manufacturing of bioresorbable electronics. The fabricated Zn conductors show excellent electrical conductivity (≈1.124 × 10 6 S m -1 ), mechanical durability, and water dissolvability. Successful demonstration of strain gauges confirms the potential application in various environmentally friendly sensors and circuits. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fast optoelectric printing of plasmonic nanoparticles into tailored circuits

NASA Astrophysics Data System (ADS)

Rodrigo, José A.

2017-04-01

Plasmonic nanoparticles are able to control light at nanometre-scale by coupling electromagnetic fields to the oscillations of free electrons in metals. Deposition of such nanoparticles onto substrates with tailored patterns is essential, for example, in fabricating plasmonic structures for enhanced sensing. This work presents an innovative micro-patterning technique, based on optoelectic printing, for fast and straightforward fabrication of curve-shaped circuits of plasmonic nanoparticles deposited onto a transparent electrode often used in optoelectronics, liquid crystal displays, touch screens, etc. We experimentally demonstrate that this kind of plasmonic structure, printed by using silver nanoparticles of 40 nm, works as a plasmonic enhanced optical device allowing for polarized-color-tunable light scattering in the visible. These findings have potential applications in biosensing and fabrication of future optoelectronic devices combining the benefits of plasmonic sensing and the functionality of transparent electrodes.

Alternatives Assessment: Partnership to Evaluate Flame Retardants in Printed Circuit Boards

EPA Pesticide Factsheets

The partnership project on flame retardants in printed circuit boards seeks to improve understanding of the environmental and human health impacts of new and current materials that can be used to meet fire safety standards

Microfluidic networks embedded in a printed circuit board

NASA Astrophysics Data System (ADS)

Dong, Liangwei; Hu, Yueli

2017-07-01

In order to improve the robustness of microfluidic networks in printed circuit board (PCB)-based microfluidic platforms, a new method was presented. A pattern in a PCB was formed using hollowed-out technology. Polydimethylsiloxane was partly filled in the hollowed-out fields after mounting an adhesive tape on the bottom of the PCB, and solidified in an oven. Then, microfluidic networks were built using soft lithography technology. Microfluidic transportation and dilution operations were demonstrated using the fabricated microfluidic platform. Results show that this method can embed microfluidic networks into a PCB, and microfluidic operations can be implemented in the microfluidic networks embedded into the PCB.

3D Printed Fluidic Hardware for DNA Assembly

DTIC Science & Technology

2015-04-10

A3909 stepper motor driver, were soldered onto the milled circuit board (Supplementary Figure 8). Custom Arduino - based firmware was written to take...initiatives such as the FabLab Foundation10. Access to digital fabrication tools and open electronics, such as Arduino and Raspberry Pi, enables access to...hardware for assembly of DNA- based genetic circuits. Solid-phase DNA synthesis has declined in price, enabling researchers to routinely design and

Printed circuit boards: a review on the perspective of sustainability.

PubMed

Canal Marques, André; Cabrera, José-María; Malfatti, Célia de Fraga

2013-12-15

Modern life increasingly requires newer equipments and more technology. In addition, the fact that society is highly consumerist makes the amount of discarded equipment as well as the amount of waste from the manufacture of new products increase at an alarming rate. Printed circuit boards, which form the basis of the electronics industry, are technological waste of difficult disposal whose recycling is complex and expensive due to the diversity of materials and components and their difficult separation. Currently, printed circuit boards have a fixing problem, which is migrating from traditional Pb-Sn alloys to lead-free alloys without definite choice. This replacement is an attempt to minimize the problem of Pb toxicity, but it does not change the problem of separation of the components for later reuse and/or recycling and leads to other problems, such as temperature rise, delamination, flaws, risks of mechanical shocks and the formation of "whiskers". This article presents a literature review on printed circuit boards, showing their structure and materials, the environmental problem related to the board, some the different alternatives for recycling, and some solutions that are being studied to reduce and/or replace the solder, in order to minimize the impact of solder on the printed circuit boards. Copyright © 2013 Elsevier Ltd. All rights reserved.

Recovery of Precious and Base Metals from Waste Printed Circuit Boards Using a Sequential Leaching Procedure

NASA Astrophysics Data System (ADS)

Batnasan, Altansukh; Haga, Kazutoshi; Shibayama, Atsushi

2018-02-01

This paper considers the issue of recycling of waste printed circuit boards (WPCBs) containing precious and base metals in appreciable amounts. High-pressure oxidative leaching (HPOL) with dilute sulfuric acid resulted in removal of a significant amount of base metals from a WPCB ash sample obtained by incineration at 800°C. The parameters investigated in the precious metal leaching from WPCB residue after HPOL included the sulfuric acid concentration, thiourea concentration, oxidant concentration, leaching temperature, and leaching time. Recovery of gold, silver, and palladium of 100%, 81%, and 13% from the WPCB residue sample was achieved by thiourea leaching under optimized conditions. The results show that the efficiency of precious metal dissolution from the WPCB sample using thiourea solution depended strongly on the concentration of both thiourea and oxidant.

Recovery of Precious and Base Metals from Waste Printed Circuit Boards Using a Sequential Leaching Procedure

NASA Astrophysics Data System (ADS)

Batnasan, Altansukh; Haga, Kazutoshi; Shibayama, Atsushi

2017-12-01

This paper considers the issue of recycling of waste printed circuit boards (WPCBs) containing precious and base metals in appreciable amounts. High-pressure oxidative leaching (HPOL) with dilute sulfuric acid resulted in removal of a significant amount of base metals from a WPCB ash sample obtained by incineration at 800°C. The parameters investigated in the precious metal leaching from WPCB residue after HPOL included the sulfuric acid concentration, thiourea concentration, oxidant concentration, leaching temperature, and leaching time. Recovery of gold, silver, and palladium of 100%, 81%, and 13% from the WPCB residue sample was achieved by thiourea leaching under optimized conditions. The results show that the efficiency of precious metal dissolution from the WPCB sample using thiourea solution depended strongly on the concentration of both thiourea and oxidant.

Evaluation of Cleanliness Test Methods for Spacecraft PCB Assemblies

NASA Astrophysics Data System (ADS)

Tegehall, P.-E.; Dunn, B. D.

2006-10-01

Ionic contamination on printed-circuit-board assemblies may cause current leakage and short-circuits. The present cleanliness requirement in ECSS-Q-70-08, "The manual soldering of high-reliability electrical connections", is that the ionic contamination shall be less than 1.56 fl-glcm2 NaCI equivalents. The relevance of the method used for measurement of the ionic contamination level, resistivity of solvent extract, has been questioned. Alternative methods are ion chromatography and measurement of surface insulation resistance, but these methods also have their drawbacks. These methods are first described and their advantages and drawbacks are discussed. This is followed by an experimental evaluation of the three methods. This was done by soldering test vehicles at four manufacturers of space electronics using their ordinary processes for soldering and cleaning printed board assemblies. The experimental evaluation showed that the ionic contamination added by the four assemblers was very small and well below the acceptance criterion in ECSS-Q-70-80. Ion-chromatography analysis showed that most of the ionic contamination on the cleaned assembled boards originated from the hot-oil fusing of the printed circuit boards. Also, the surface insulation resistance was higher on the assembled boards compared to the bare printed circuit boards. Since strongly activated fluxes are normally used when printed circuit boards are hot-oil fused, it is essential that they are thoroughly cleaned in order to achieve low contamination levels on the final printed-board assemblies.

Surface-Embedded Stretchable Electrodes by Direct Printing and their Uses to Fabricate Ultrathin Vibration Sensors and Circuits for 3D Structures.

PubMed

Song, Jun Hyuk; Kim, Young-Tae; Cho, Sunghwan; Song, Woo-Jin; Moon, Sungmin; Park, Chan-Gyung; Park, Soojin; Myoung, Jae Min; Jeong, Unyong

2017-11-01

Printing is one of the easy and quick ways to make a stretchable wearable electronics. Conventional printing methods deposit conductive materials "on" or "inside" a rubber substrate. The conductors made by such printing methods cannot be used as device electrodes because of the large surface topology, poor stretchability, or weak adhesion between the substrate and the conducting material. Here, a method is presented by which conductive materials are printed in the way of being surface-embedded in the rubber substrate; hence, the conductors can be widely used as device electrodes and circuits. The printing process involves a direct printing of a metal precursor solution in a block-copolymer rubber substrate and chemical reduction of the precursor into metal nanoparticles. The electrical conductivity and sensitivity to the mechanical deformation can be controlled by adjusting the number of printing operations. The fabrication of highly sensitive vibration sensors is thus presented, which can detect weak pulses and sound waves. In addition, this work takes advantage of the viscoelasticity of the composite conductor to fabricate highly conductive stretchable circuits for complicated 3D structures. The printed electrodes are also used to fabricate a stretchable electrochemiluminescence display. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CMOS Imaging of Pin-Printed Xerogel-Based Luminescent Sensor Microarrays.

PubMed

Yao, Lei; Yung, Ka Yi; Khan, Rifat; Chodavarapu, Vamsy P; Bright, Frank V

2010-12-01

We present the design and implementation of a luminescence-based miniaturized multisensor system using pin-printed xerogel materials which act as host media for chemical recognition elements. We developed a CMOS imager integrated circuit (IC) to image the luminescence response of the xerogel-based sensor array. The imager IC uses a 26 × 20 (520 elements) array of active pixel sensors and each active pixel includes a high-gain phototransistor to convert the detected optical signals into electrical currents. The imager includes a correlated double sampling circuit and pixel address/digital control circuit; the image data is read-out as coded serial signal. The sensor system uses a light-emitting diode (LED) to excite the target analyte responsive luminophores doped within discrete xerogel-based sensor elements. As a prototype, we developed a 4 × 4 (16 elements) array of oxygen (O 2 ) sensors. Each group of 4 sensor elements in the array (arranged in a row) is designed to provide a different and specific sensitivity to the target gaseous O 2 concentration. This property of multiple sensitivities is achieved by using a strategic mix of two oxygen sensitive luminophores ([Ru(dpp) 3 ] 2+ and ([Ru(bpy) 3 ] 2+ ) in each pin-printed xerogel sensor element. The CMOS imager consumes an average power of 8 mW operating at 1 kHz sampling frequency driven at 5 V. The developed prototype system demonstrates a low cost and miniaturized luminescence multisensor system.

Soldering Tool for Integrated Circuits

NASA Technical Reports Server (NTRS)

Takahashi, Ted H.

1987-01-01

Many connections soldered simultaneously in confined spaces. Improved soldering tool bonds integrated circuits onto printed-circuit boards. Intended especially for use with so-called "leadless-carrier" integrated circuits.

Self-shielding printed circuit boards for high frequency amplifiers and transmitters

NASA Technical Reports Server (NTRS)

Galvin, D.

1969-01-01

Printed circuit boards retaining as much copper as possible provide electromagnetic shielding between stages of the high frequency amplifiers and transmitters. Oscillation is prevented, spurious output signals are reduced, and multiple stages are kept isolated from each other, both thermally and electrically.

Packaging strategy for maximizing the performance of a screen printed piezoelectric energy harvester

NASA Astrophysics Data System (ADS)

Zhang, Z.; Zhu, D.; Tudor, M. J.; Beeby, S. P.

2013-12-01

This paper reports the extended design and simulation of a screen printed piezoelectric energy harvester. The proposed design was based on a previous credit card sized smart tag sensor node, and packages the power conditioning circuit in the free space above the tungsten proof mass layer. This approach enables electronic components to be mounted onto the cantilever beam, which provides additional weight at the tip of the cantilever structure. The design structure contains a T-shape cantilever beam with size of 47 mm × 30 mm × 0.85 mm which is fabricated using screen printing. ANSYS simulation results predict the revised architecture can generate 421.9 μW approximately twice of the RMS power produced by the original design along with a higher open-circuit RMS Voltage of 8.0 V while the resonant frequency is dropped to 53.4 Hz.

Flexible hybrid circuit fully inkjet-printed: Surface mount devices assembled by silver nanoparticles-based inkjet ink

NASA Astrophysics Data System (ADS)

Arrese, J.; Vescio, G.; Xuriguera, E.; Medina-Rodriguez, B.; Cornet, A.; Cirera, A.

2017-03-01

Nowadays, inkjet-printed devices such as transistors are still unstable in air and have poor performances. Moreover, the present electronics applications require a high degree of reliability and quality of their properties. In order to accomplish these application requirements, hybrid electronics is fulfilled by combining the advantages of the printing technologies with the surface-mount technology. In this work, silver nanoparticle-based inkjet ink (AgNP ink) is used as a novel approach to connect surface-mount devices (SMDs) onto inkjet-printed pads, conducted by inkjet printing technology. Excellent quality AgNP ink-junctions are ensured with high resolution picoliter drop jetting at low temperature (˜150 °C). Electrical, mechanical, and morphological characterizations are carried out to assess the performance of the AgNP ink junction. Moreover, AgNP ink is compared with common benchmark materials (i.e., silver epoxy and solder). Electrical contact resistance characterization shows a similar performance between the AgNP ink and the usual ones. Mechanical characterization shows comparable shear strength for AgNP ink and silver epoxy, and both present higher adhesion than solder. Morphological inspections by field-emission scanning electron microscopy confirm a high quality interface of the silver nanoparticle interconnection. Finally, a flexible hybrid circuit on paper controlled by an Arduino board is manufactured, demonstrating the viability and scalability of the AgNP ink assembling technique.

Inkjet printing of metal-oxide-based transparent thin-film capacitors

NASA Astrophysics Data System (ADS)

Matavž, A.; Malič, B.; Bobnar, V.

2017-12-01

We report on the inkjet printing of transparent, thin-film capacitors (TTFCs) composed of indium-zinc-oxide electrodes and a tantalum-oxide-based dielectric on glass substrates. The printing parameters were adapted for the sequential deposition of functional layers, resulting in approximately 100-nm-thick transparent capacitors with a uniform thickness. The relatively high electrical resistivity of the electrodes is reflected in the frequency dispersive dielectric behaviour, which is explained in terms of an equivalent circuit. The resistivity of the electrode strongly decreases with the number of printing passes; consequently, any misalignment of the printed layers is detected in the measured response. At low frequency, the TTFCs show a stable intrinsic dielectric response and a high capacitance density of ˜280 nF/cm2. The good dielectric performance as well as the low leakage-current density (8 × 10-7 A/cm2 at 1 MV cm-1) of our capacitors indicates that inkjet printing can be used to produce all-printed, high-quality electrical devices.

Developing and Evaluating a Flexible Wireless Microcoil Array Based Integrated Interface for Epidural Cortical Stimulation.

PubMed

Wang, Xing; Chaudhry, Sharjeel A; Hou, Wensheng; Jia, Xiaofeng

2017-02-05

Stroke leads to serious long-term disability. Electrical epidural cortical stimulation has made significant improvements in stroke rehabilitation therapy. We developed a preliminary wireless implantable passive interface, which consists of a stimulating surface electrode, receiving coil, and single flexible passive demodulated circuit printed by flexible printed circuit (FPC) technique and output pulse voltage stimulus by inductively coupling an external circuit. The wireless implantable board was implanted in cats' unilateral epidural space for electrical stimulation of the primary visual cortex (V1) while the evoked responses were recorded on the contralateral V1 using a needle electrode. The wireless implantable board output stable monophasic voltage stimuli. The amplitude of the monophasic voltage output could be adjusted by controlling the voltage of the transmitter circuit within a range of 5-20 V. In acute experiment, cortico-cortical evoked potential (CCEP) response was recorded on the contralateral V1. The amplitude of N2 in CCEP was modulated by adjusting the stimulation intensity of the wireless interface. These results demonstrated that a wireless interface based on a microcoil array can offer a valuable tool for researchers to explore electrical stimulation in research and the dura mater-electrode interface can effectively transmit electrical stimulation.

"Printed-circuit" rectenna

NASA Technical Reports Server (NTRS)

Dickinson, R. M.

1977-01-01

Rectifying antenna is less bulky structure for absorbing transmitted microwave power and converting it into electrical current. Printed-circuit approach, using microstrip technology and circularly polarized antenna, makes polarization orientation unimportant and allows much smaller arrays for given performance. Innovation is particularly useful with proposed electric vehicles powered by beam microwaves.

Board Saver for Use with Developmental FPGAs

NASA Technical Reports Server (NTRS)

Berkun, Andrew

2009-01-01

A device denoted a board saver has been developed as a means of reducing wear and tear of a printed-circuit board onto which an antifuse field programmable gate array (FPGA) is to be eventually soldered permanently after a number of design iterations. The need for the board saver or a similar device arises because (1) antifuse-FPGA design iterations are common and (2) repeated soldering and unsoldering of FPGAs on the printed-circuit board to accommodate design iterations can wear out the printed-circuit board. The board saver is basically a solderable/unsolderable FPGA receptacle that is installed temporarily on the printed-circuit board. The board saver is, more specifically, a smaller, square-ring-shaped, printed-circuit board (see figure) that contains half via holes one for each contact pad along its periphery. As initially fabricated, the board saver is a wider ring containing full via holes, but then it is milled along its outer edges, cutting the via holes in half and laterally exposing their interiors. The board saver is positioned in registration with the designated FPGA footprint and each via hole is soldered to the outer portion of the corresponding FPGA contact pad on the first-mentioned printed-circuit board. The via-hole/contact joints can be inspected visually and can be easily unsoldered later. The square hole in the middle of the board saver is sized to accommodate the FPGA, and the thickness of the board saver is the same as that of the FPGA. Hence, when a non-final FPGA is placed in the square hole, the combination of the non-final FPGA and the board saver occupy no more area and thickness than would a final FPGA soldered directly into its designated position on the first-mentioned circuit board. The contact leads of a non-final FPGA are not bent and are soldered, at the top of the board saver, to the corresponding via holes. A non-final FPGA can readily be unsoldered from the board saver and replaced by another one. Once the final FPGA design has been determined, the board saver can be unsoldered from the contact pads on the first-mentioned printed-circuit board and replaced by the final FPGA.

Printed 2 V-operating organic inverter arrays employing a small-molecule/polymer blend

NASA Astrophysics Data System (ADS)

Shiwaku, Rei; Takeda, Yasunori; Fukuda, Takashi; Fukuda, Kenjiro; Matsui, Hiroyuki; Kumaki, Daisuke; Tokito, Shizuo

2016-10-01

Printed organic thin-film transistors (OTFTs) are well suited for low-cost electronic applications, such as radio frequency identification (RFID) tags and sensors. Achieving both high carrier mobility and uniform electrical characteristics in printed OTFT devices is essential in these applications. Here, we report on printed high-performance OTFTs and circuits using silver nanoparticle inks for the source/drain electrodes and a blend of dithieno[2,3-d2‧,3‧-d‧]benzo[1,2-b4,5-b‧]dithiophene (DTBDT-C6) and polystyrene for the organic semiconducting layer. A high saturation region mobility of 1.0 cm2 V-1 s-1 at low operation voltage of -5 V was obtained for relatively short channel lengths of 9 μm. All fifteen of the printed pseudo-CMOS inverter circuits were formed on a common substrate and operated at low operation voltage of 2 V with the total variation in threshold voltage of 0.35 V. Consequently, the printed OTFT devices can be used in more complex integrated circuit applications requiring low manufacturing cost over large areas.

Printed 2 V-operating organic inverter arrays employing a small-molecule/polymer blend.

PubMed

Shiwaku, Rei; Takeda, Yasunori; Fukuda, Takashi; Fukuda, Kenjiro; Matsui, Hiroyuki; Kumaki, Daisuke; Tokito, Shizuo

2016-10-04

Printed organic thin-film transistors (OTFTs) are well suited for low-cost electronic applications, such as radio frequency identification (RFID) tags and sensors. Achieving both high carrier mobility and uniform electrical characteristics in printed OTFT devices is essential in these applications. Here, we report on printed high-performance OTFTs and circuits using silver nanoparticle inks for the source/drain electrodes and a blend of dithieno[2,3-d;2',3'-d']benzo[1,2-b;4,5-b']dithiophene (DTBDT-C 6 ) and polystyrene for the organic semiconducting layer. A high saturation region mobility of 1.0 cm 2  V -1  s -1 at low operation voltage of -5 V was obtained for relatively short channel lengths of 9 μm. All fifteen of the printed pseudo-CMOS inverter circuits were formed on a common substrate and operated at low operation voltage of 2 V with the total variation in threshold voltage of 0.35 V. Consequently, the printed OTFT devices can be used in more complex integrated circuit applications requiring low manufacturing cost over large areas.

Fractal dendrite-based electrically conductive composites for laser-scribed flexible circuits

PubMed Central

Yang, Cheng; Cui, Xiaoya; Zhang, Zhexu; Chiang, Sum Wai; Lin, Wei; Duan, Huan; Li, Jia; Kang, Feiyu; Wong, Ching-Ping

2015-01-01

Fractal metallic dendrites have been drawing more attentions recently, yet they have rarely been explored in electronic printing or packaging applications because of the great challenges in large-scale synthesis and limited understanding in such applications. Here we demonstrate a controllable synthesis of fractal Ag micro-dendrites at the hundred-gram scale. When used as the fillers for isotropically electrically conductive composites (ECCs), the unique three-dimensional fractal geometrical configuration and low-temperature sintering characteristic render the Ag micro dendrites with an ultra-low electrical percolation threshold of 0.97 vol% (8 wt%). The ultra-low percolation threshold and self-limited fusing ability may address some critical challenges in current interconnect technology for microelectronics. For example, only half of the laser-scribe energy is needed to pattern fine circuit lines printed using the present ECCs, showing great potential for wiring ultrathin circuits for high performance flexible electronics. PMID:26333352

Organic transistors manufactured using inkjet technology with subfemtoliter accuracy

PubMed Central

Sekitani, Tsuyoshi; Noguchi, Yoshiaki; Zschieschang, Ute; Klauk, Hagen; Someya, Takao

2008-01-01

A major obstacle to the development of organic transistors for large-area sensor, display, and circuit applications is the fundamental compromise between manufacturing efficiency, transistor performance, and power consumption. In the past, improving the manufacturing efficiency through the use of printing techniques has inevitably resulted in significantly lower performance and increased power consumption, while attempts to improve performance or reduce power have led to higher process temperatures and increased manufacturing cost. Here, we lift this fundamental limitation by demonstrating subfemtoliter inkjet printing to define metal contacts with single-micrometer resolution on the surface of high-mobility organic semiconductors to create high-performance p-channel and n-channel transistors and low-power complementary circuits. The transistors employ an ultrathin low-temperature gate dielectric based on a self-assembled monolayer that allows transistors and circuits on rigid and flexible substrates to operate with very low voltages. PMID:18362348

Water Activated Graphene Oxide Transfer Using Wax Printed Membranes for Fast Patterning of a Touch Sensitive Device.

PubMed

Baptista-Pires, Luis; Mayorga-Martínez, Carmen C; Medina-Sánchez, Mariana; Montón, Helena; Merkoçi, Arben

2016-01-26

We demonstrate a graphene oxide printing technology using wax printed membranes for the fast patterning and water activation transfer using pressure based mechanisms. The wax printed membranes have 50 μm resolution, longtime stability and infinite shaping capability. The use of these membranes complemented with the vacuum filtration of graphene oxide provides the control over the thickness. Our demonstration provides a solvent free methodology for printing graphene oxide devices in all shapes and all substrates using the roll-to-roll automatized mechanism present in the wax printing machine. Graphene oxide was transferred over a wide variety of substrates as textile or PET in between others. Finally, we developed a touch switch sensing device integrated in a LED electronic circuit.

Testing of printed circuit board solder joints by optical correlation

NASA Technical Reports Server (NTRS)

Espy, P. N.

1975-01-01

An optical correlation technique for the nondestructive evaluation of printed circuit board solder joints was evaluated. Reliable indications of induced stress levels in solder joint lead wires are achievable. Definite relations between the inherent strength of a solder joint, with its associated ability to survive stress, are demonstrable.

Space shuttle main engine controller assembly, phase C-D. [with lagging system design and analysis

NASA Technical Reports Server (NTRS)

1973-01-01

System design and system analysis and simulation are slightly behind schedule, while design verification testing has improved. Input/output circuit design has improved, but digital computer unit (DCU) and mechanical design continue to lag. Part procurement was impacted by delays in printed circuit board, assembly drawing releases. These are the result of problems in generating suitable printed circuit artwork for the very complex and high density multilayer boards.

Highly Conductive Nano-Silver Circuits by Inkjet Printing

NASA Astrophysics Data System (ADS)

Zhu, Dongbin; Wu, Minqiang

2018-06-01

Inkjet technology has become popular in the field of printed electronics due to its superior properties such as simple processes and printable complex patterns. Electrical conductivity of the circuits is one of the key factors in measuring the performance of printed electronics, which requires great material properties and a manufactured process. With excellent conductivity and ductility, silver is an ideal material as the wire connecting components. This review summarizes the progress of conductivity studies on inkjet printed nano-silver lines, including ink composition and nanoparticle morphology, deposition of nano-silver lines with uniform and high aspect ratios, sintering mechanisms and alternative methods of thermal sintering. Finally, the research direction on inkjet printed electronics is proposed.

A Wireless Sensor System for Real-Time Measurement of Pressure Profiles at Lower Limb Protheses to Ensure Proper Fitting

DTIC Science & Technology

2011-10-01

been developed. The next step is to develop a the base technology into a grid like mapping sensor, construct the excitation and detection circuits...the project involves advancing the base technology into a grid -like mapping se nsor, constructing the excitation and detection circuits, modifying and...further. In conclusion, the screen printing and etching process allows for precise repeat able production of sensing elements for grid fabrication

Characterization of shredded television scrap and implications for materials recovery.

PubMed

Cui, Jirang; Forssberg, Eric

2007-01-01

Characterization of TV scrap was carried out by using a variety of methods, such as chemical analysis, particle size and shape analysis, liberation degree analysis, thermogravimetric analysis, sink-float test, and IR spectrometry. A comparison of TV scrap, personal computer scrap, and printed circuit board scrap shows that the content of non-ferrous metals and precious metals in TV scrap is much lower than that in personal computer scrap or printed circuit board scrap. It is expected that recycling of TV scrap will not be cost-effective by utilizing conventional manual disassembly. The result of particle shape analysis indicates that the non-ferrous metal particles in TV scrap formed as a variety of shapes; it is much more heterogeneous than that of plastics and printed circuit boards. Furthermore, the separability of TV scrap using density-based techniques was evaluated by the sink-float test. The result demonstrates that a high recovery of copper could be obtained by using an effective gravity separation process. Identification of plastics shows that the major plastic in TV scrap is high impact polystyrene. Gravity separation of plastics may encounter some challenges in separation of plastics from TV scrap because of specific density variations.

Recycling-oriented characterization of plastic frames and printed circuit boards from mobile phones by electronic and chemical imaging.

PubMed

Palmieri, Roberta; Bonifazi, Giuseppe; Serranti, Silvia

2014-11-01

This study characterizes the composition of plastic frames and printed circuit boards from end-of-life mobile phones. This knowledge may help define an optimal processing strategy for using these items as potential raw materials. Correct handling of such a waste is essential for its further "sustainable" recovery, especially to maximize the extraction of base, rare and precious metals, minimizing the environmental impact of the entire process chain. A combination of electronic and chemical imaging techniques was thus examined, applied and critically evaluated in order to optimize the processing, through the identification and the topological assessment of the materials of interest and their quantitative distribution. To reach this goal, end-of-life mobile phone derived wastes have been systematically characterized adopting both "traditional" (e.g. scanning electronic microscopy combined with microanalysis and Raman spectroscopy) and innovative (e.g. hyperspectral imaging in short wave infrared field) techniques, with reference to frames and printed circuit boards. Results showed as the combination of both the approaches (i.e. traditional and classical) could dramatically improve recycling strategies set up, as well as final products recovery. Copyright © 2014 Elsevier Ltd. All rights reserved.

Heat sinking for printed circuitry

DOEpatents

Wilson, S.K.; Richardson, G.; Pinkerton, A.L.

1984-09-11

A flat pak or other solid-state device mounted on a printed circuit board directly over a hole extends therethrough so that the bottom of the pak or device extends beyond the bottom of the circuit board. A heat sink disposed beneath the circuit board contacts the bottom of the pak or device and provides direct heat sinking thereto. Pressure may be applied to the top of the pak or device to assure good mechanical and thermal contact with the heat sink.

Flexible circuits with integrated switches for robotic shape sensing

NASA Astrophysics Data System (ADS)

Harnett, C. K.

2016-05-01

Digital switches are commonly used for detecting surface contact and limb-position limits in robotics. The typical momentary-contact digital switch is a mechanical device made from metal springs, designed to connect with a rigid printed circuit board (PCB). However, flexible printed circuits are taking over from the rigid PCB in robotics because the circuits can bend while carrying signals and power through moving joints. This project is motivated by a previous work where an array of surface-mount momentary contact switches on a flexible circuit acted as an all-digital shape sensor compatible with the power resources of energy harvesting systems. Without a rigid segment, the smallest commercially-available surface-mount switches would detach from the flexible circuit after several bending cycles, sometimes violently. This report describes a low-cost, conductive fiber based method to integrate electromechanical switches into flexible circuits and other soft, bendable materials. Because the switches are digital (on/off), they differ from commercially-available continuous-valued bend/flex sensors. No amplification or analog-to-digital conversion is needed to read the signal, but the tradeoff is that the digital switches only give a threshold curvature value. Boundary conditions on the edges of the flexible circuit are key to setting the threshold curvature value for switching. This presentation will discuss threshold-setting, size scaling of the design, automation for inserting a digital switch into the flexible circuit fabrication process, and methods for reconstructing a shape from an array of digital switch states.

Testing Services

NASA Technical Reports Server (NTRS)

1993-01-01

Trace Laboratories is an independent testing laboratory specializing in testing printed circuit boards, automotive products and military hardware. Technical information from NASA Tech Briefs and two subsequent JPL Technical Support packages have assisted Trace in testing surface insulation resistance on printed circuit board materials. Testing time was reduced and customer service was improved because of Jet Propulsion Laboratory technical support packages.

78 FR 75360 - Notice of Issuance of Final Determination Concerning Certain Ethernet Switches

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-11

... printed circuit board assembly (``PCBA''), chassis, top cover, power supply, and fans. The switches... printed circuit board is populated with various electronic components to make a PCBA. 2. The PCBA is... Singapore. You argue that without the EOS software, the units exported from Singapore lack the intelligence...

Modular integration of electronics and microfluidic systems using flexible printed circuit boards.

PubMed

Wu, Amy; Wang, Lisen; Jensen, Erik; Mathies, Richard; Boser, Bernhard

2010-02-21

Microfluidic systems offer an attractive alternative to conventional wet chemical methods with benefits including reduced sample and reagent volumes, shorter reaction times, high-throughput, automation, and low cost. However, most present microfluidic systems rely on external means to analyze reaction products. This substantially adds to the size, complexity, and cost of the overall system. Electronic detection based on sub-millimetre size integrated circuits (ICs) has been demonstrated for a wide range of targets including nucleic and amino acids, but deployment of this technology to date has been limited due to the lack of a flexible process to integrate these chips within microfluidic devices. This paper presents a modular and inexpensive process to integrate ICs with microfluidic systems based on standard printed circuit board (PCB) technology to assemble the independently designed microfluidic and electronic components. The integrated system can accommodate multiple chips of different sizes bonded to glass or PDMS microfluidic systems. Since IC chips and flex PCB manufacturing and assembly are industry standards with low cost, the integrated system is economical for both laboratory and point-of-care settings.

Printed 2 V-operating organic inverter arrays employing a small-molecule/polymer blend

PubMed Central

Shiwaku, Rei; Takeda, Yasunori; Fukuda, Takashi; Fukuda, Kenjiro; Matsui, Hiroyuki; Kumaki, Daisuke; Tokito, Shizuo

2016-01-01

Printed organic thin-film transistors (OTFTs) are well suited for low-cost electronic applications, such as radio frequency identification (RFID) tags and sensors. Achieving both high carrier mobility and uniform electrical characteristics in printed OTFT devices is essential in these applications. Here, we report on printed high-performance OTFTs and circuits using silver nanoparticle inks for the source/drain electrodes and a blend of dithieno[2,3-d;2′,3′-d′]benzo[1,2-b;4,5-b′]dithiophene (DTBDT-C6) and polystyrene for the organic semiconducting layer. A high saturation region mobility of 1.0 cm2 V−1 s−1 at low operation voltage of −5 V was obtained for relatively short channel lengths of 9 μm. All fifteen of the printed pseudo-CMOS inverter circuits were formed on a common substrate and operated at low operation voltage of 2 V with the total variation in threshold voltage of 0.35 V. Consequently, the printed OTFT devices can be used in more complex integrated circuit applications requiring low manufacturing cost over large areas. PMID:27698493

Biomedical Diagnostics Enabled by Integrated Organic and Printed Electronics.

PubMed

Ahmadraji, Termeh; Gonzalez-Macia, Laura; Ritvonen, Tapio; Willert, Andreas; Ylimaula, Satu; Donaghy, David; Tuurala, Saara; Suhonen, Mika; Smart, Dave; Morrin, Aoife; Efremov, Vitaly; Baumann, Reinhard R; Raja, Munira; Kemppainen, Antti; Killard, Anthony J

2017-07-18

Organic and printed electronics integration has the potential to revolutionize many technologies, including biomedical diagnostics. This work demonstrates the successful integration of multiple printed electronic functionalities into a single device capable of the measurement of hydrogen peroxide and total cholesterol. The single-use device employed printed electrochemical sensors for hydrogen peroxide electroreduction integrated with printed electrochromic display and battery. The system was driven by a conventional electronic circuit designed to illustrate the complete integration of silicon integrated circuits via pick and place or using organic electronic circuits. The device was capable of measuring 8 μL samples of both hydrogen peroxide (0-5 mM, 2.72 × 10 -6 A·mM -1 ) and total cholesterol in serum from 0 to 9 mM (1.34 × 10 -8 A·mM -1 , r 2 = 0.99, RSD < 10%, n = 3), and the result was output on a semiquantitative linear bar display. The device could operate for 10 min via a printed battery, and display the result for many hours or days. A mobile phone "app" was also capable of reading the test result and transmitting this to a remote health care provider. Such a technology could allow improved management of conditions such as hypercholesterolemia.

Carbon Based Transistors and Nanoelectronic Devices

NASA Astrophysics Data System (ADS)

Rouhi, Nima

Carbon based materials (carbon nanotube and graphene) has been extensively researched during the past decade as one of the promising materials to be used in high performance device technology. In long term it is thought that they may replace digital and/or analog electronic devices, due to their size, near-ballistic transport, and high stability. However, a more realistic point of insertion into market may be the printed nanoelectronic circuits and sensors. These applications include printed circuits for flexible electronics and displays, large-scale bendable electrical contacts, bio-membranes and bio sensors, RFID tags, etc. In order to obtain high performance thin film transistors (as the basic building block of electronic circuits) one should be able to manufacture dense arrays of all semiconducting nanotubes. Besides, graphene synthesize and transfer technology is in its infancy and there is plenty of room to improve the current techniques. To realize the performance of nanotube and graphene films in such systems, we need to economically fabricate large-scale devices based on these materials. Following that the performance control over such devices should also be considered for future design variations for broad range of applications. Here we have first investigated carbon nanotube ink as the base material for our devices. The primary ink used consisted of both metallic and semiconducting nanotubes which resulted in networks suitable for moderate-resistivity electrical connections (such as interconnects) and rfmatching circuits. Next, purified all-semiconducting nanotube ink was used to fabricate waferscale, high performance (high mobility, and high on/off ratio) thin film transistors for printed electronic applications. The parameters affecting device performance were studied in detail to establish a roadmap for the future of purified nanotube ink printed thin film transistors. The trade of between mobility and on/off ratio of such devices was studied and the effect of nanotube network density was explained in detail. On the other hand, graphene transfer technology was explored here as well. Annealing techniques were utilized to deposit clean graphene on arbitrary substrates. Raman spectroscopy and Raman data analysis was used to confirm the clean process. Furthermore, suspended graphene membrane was fabricated using single and multi-layer graphene films. This can make a major impact on graphene based transistors and bio-nano sensors technology.

Printed Antennas Made Reconfigurable by Use of MEMS Switches

NASA Technical Reports Server (NTRS)

Simons, Rainee N.

2005-01-01

A class of reconfigurable microwave antennas now undergoing development comprise fairly conventional printed-circuit feed elements and radiating patches integrated with novel switches containing actuators of the microelectromechanical systems (MEMS) type. In comparison with solid-state electronic control devices incorporated into some prior printed microwave antennas, the MEMS-based switches in these antennas impose lower insertion losses and consume less power. Because the radio-frequency responses of the MEMS switches are more nearly linear, they introduce less signal distortion. In addition, construction and operation are simplified because only a single DC bias line is needed to control each MEMS actuator.

Glass Fibers for Printed Circuit Boards

NASA Astrophysics Data System (ADS)

Longobardo, Anthony V.

Fiberglass imparts numerous positive benefits to modern printed circuit boards. Reinforced laminate composites have an excellent cost-performance relationship that makes sense for most applications. At the leading edge of the technology, new glass fibers with improved properties, in combination with the best resin systems available, are able to meet very challenging performance, cost, and regulatory demands while remaining manufacturable.

Printed-Circuit-Board Soldering Training for Group IV Personnel.

ERIC Educational Resources Information Center

Hooprich, E. A.; Matlock, E. W.

As part of a larger program to determine which Navy skills can be learned by lower aptitude personnel, and which methods and techniques would be most effective, an experimental course in printed circuit board soldering was given to 186 Group IV students in 13 classes. Two different training approaches--one stressing instructor guidance and the…

Fully-printed high-performance organic thin-film transistors and circuitry on one-micron-thick polymer films

NASA Astrophysics Data System (ADS)

Fukuda, Kenjiro; Takeda, Yasunori; Yoshimura, Yudai; Shiwaku, Rei; Tran, Lam Truc; Sekine, Tomohito; Mizukami, Makoto; Kumaki, Daisuke; Tokito, Shizuo

2014-06-01

Thin, ultra-flexible devices that can be manufactured in a process that covers a large area will be essential to realizing low-cost, wearable electronic applications including foldable displays and medical sensors. The printing technology will be instrumental in fabricating these novel electronic devices and circuits; however, attaining fully printed devices on ultra-flexible films in large areas has typically been a challenge. Here we report on fully printed organic thin-film transistor devices and circuits fabricated on 1-μm-thick parylene-C films with high field-effect mobility (1.0 cm2 V-1 s-1) and fast operating speeds (about 1 ms) at low operating voltages. The devices were extremely light (2 g m-2) and exhibited excellent mechanical stability. The devices remained operational even under 50% compressive strain without significant changes in their performance. These results represent significant progress in the fabrication of fully printed organic thin-film transistor devices and circuits for use in unobtrusive electronic applications such as wearable sensors.

Multidisciplinary analysis and design of printed wiring boards

NASA Astrophysics Data System (ADS)

Fulton, Robert E.; Hughes, Joseph L.; Scott, Waymond R., Jr.; Umeagukwu, Charles; Yeh, Chao-Pin

1991-04-01

Modern printed wiring board design depends on electronic prototyping using computer-based simulation and design tools. Existing electrical computer-aided design (ECAD) tools emphasize circuit connectivity with only rudimentary analysis capabilities. This paper describes a prototype integrated PWB design environment denoted Thermal Structural Electromagnetic Testability (TSET) being developed at Georgia Tech in collaboration with companies in the electronics industry. TSET provides design guidance based on enhanced electrical and mechanical CAD capabilities including electromagnetic modeling testability analysis thermal management and solid mechanics analysis. TSET development is based on a strong analytical and theoretical science base and incorporates an integrated information framework and a common database design based on a systematic structured methodology.

Printing Electronic Components from Copper-Infused Ink and Thermoplastic Mediums

NASA Astrophysics Data System (ADS)

Flowers, Patrick F.

The demand for printable electronics has sharply increased in recent years and is projected to continue to rise. Unfortunately, electronic materials which are suitable for desired applications while being compatible with available printing techniques are still often lacking. This thesis addresses two such challenging areas. In the realm of two-dimensional ink-based printing of electronics, a major barrier to the realization of printable computers that can run programs is the lack of a solution-coatable non-volatile memory with performance metrics comparable to silicon-based devices. To address this deficiency, I developed a nonvolatile memory based on Cu-SiO2 core-shell nanowires that can be printed from solution and exhibits on-off ratios of 106, switching speeds of 50 ns, a low operating voltage of 2 V, and operates for at least 104 cycles without failure. Each of these metrics is similar to or better than Flash memory (the write speed is 20 times faster than Flash). Memory architectures based on the individual memory cells demonstrated here could enable the printing of the more complex, embedded computing devices that are expected to make up an internet of things. Recently, the exploration of three-dimensional printing techniques to fabricate electronic materials began. A suitable general-purpose conductive thermoplastic filament was not available, however. In this work I examine the current state of conductive thermoplastic filaments, including a newly-released highly conductive filament that my lab has produced which we call Electrifi. I focus on the use of dual-material fused filament fabrication (FFF) to 3D print electronic components (conductive traces, resistors, capacitors, inductors) and circuits (a fully-printed high-pass filter). The resistivity of traces printed from conductive thermoplastic filaments made with carbon-black, graphene, and copper as conductive fillers was found to be 12, 0.78, and 0.014 ohm cm, respectively, enabling the creation of resistors with resistances spanning 3 orders of magnitude. The carbon black and graphene filaments were brittle and fractured easily, but the copper-based filament could be bent at least 500 times with little change in its resistance. Impedance measurements made on the thermoplastic filaments demonstrate that the copper-based filament had an impedance similar to a conductive PCB trace at 1 MHz. Dual material 3D printing was used to fabricate a variety of inductors and capacitors with properties that could be predictably tuned by modifying either the geometry of the components, or the materials used to fabricate the components. These resistors, capacitors, and inductors were combined to create a fully 3D printed high-pass filter with properties comparable to its conventional counterparts. The relatively low impedance of the copper-based filament enable its use to 3D print a receiver coil for wireless power transfer. We also demonstrate the ability to embed and connect surface mounted components in 3D printed objects with a low-cost ($1,000 in parts), open source dual-material 3D printer. This work thus demonstrates the potential for FFF 3D printing to create complex, three-dimensional circuits composed of either embedded or fully-printed electronic components.

3D nanostructured inkjet printed graphene via UV-pulsed laser irradiation enables paper-based electronics and electrochemical devices.

PubMed

Das, Suprem R; Nian, Qiong; Cargill, Allison A; Hondred, John A; Ding, Shaowei; Saei, Mojib; Cheng, Gary J; Claussen, Jonathan C

2016-09-21

Emerging research on printed and flexible graphene-based electronics is beginning to show tremendous promise for a wide variety of fields including wearable sensors and thin film transistors. However, post-print annealing/reduction processes that are necessary to increase the electrical conductivity of the printed graphene degrade sensitive substrates (e.g., paper) and are whole substrate processes that are unable to selectively anneal/reduce only the printed graphene-leaving sensitive device components exposed to damaging heat or chemicals. Herein a pulsed laser process is introduced that can selectively irradiate inkjet printed reduced graphene oxide (RGO) and subsequently improve the electrical conductivity (Rsheet∼0.7 kΩ□(-1)) of printed graphene above previously published reports. Furthermore, the laser process is capable of developing 3D petal-like graphene nanostructures from 2D planar printed graphene. These visible morphological changes display favorable electrochemical sensing characteristics-ferricyanide cyclic voltammetry with a redox peak separation (ΔEp) ≈ 0.7 V as well as hydrogen peroxide (H2O2) amperometry with a sensitivity of 3.32 μA mM(-1) and a response time of <5 s. Thus this work paves the way for not only paper-based electronics with graphene circuits, it enables the creation of low-cost and disposable graphene-based electrochemical electrodes for myriad applications including sensors, biosensors, fuel cells, and theranostic devices.

Fabrication of Nanoscale Circuits on Inkjet-Printing Patterned Substrates.

PubMed

Chen, Shuoran; Su, Meng; Zhang, Cong; Gao, Meng; Bao, Bin; Yang, Qiang; Su, Bin; Song, Yanlin

2015-07-08

Nanoscale circuits are fabricated by assembling different conducting materials (e.g., metal nanoparticles, metal nano-wires, graphene, carbon nanotubes, and conducting polymers) on inkjet-printing patterned substrates. This non-litho-graphy strategy opens a new avenue for integrating conducting building blocks into nanoscale devices in a cost-efficient manner. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Treatment of Wastewater from Electroplating, Metal Finishing and Printed Circuit Board Manufacturing. Operation of Wastewater Treatment Plants Volume 4.

ERIC Educational Resources Information Center

California State Univ., Sacramento. Dept. of Civil Engineering.

One of four manuals dealing with the operation of wastewater plants, this document was designed to address the treatment of wastewater from electroplating, metal finishing, and printed circuit board manufacturing. It emphasizes how to operate and maintain facilities which neutralize acidic and basic waters; treat waters containing metals; destroy…

Logic circuits composed of flexible carbon nanotube thin-film transistor and ultra-thin polymer gate dielectric

PubMed Central

Lee, Dongil; Yoon, Jinsu; Lee, Juhee; Lee, Byung-Hyun; Seol, Myeong-Lok; Bae, Hagyoul; Jeon, Seung-Bae; Seong, Hyejeong; Im, Sung Gap; Choi, Sung-Jin; Choi, Yang-Kyu

2016-01-01

Printing electronics has become increasingly prominent in the field of electronic engineering because this method is highly efficient at producing flexible, low-cost and large-scale thin-film transistors. However, TFTs are typically constructed with rigid insulating layers consisting of oxides and nitrides that are brittle and require high processing temperatures, which can cause a number of problems when used in printed flexible TFTs. In this study, we address these issues and demonstrate a method of producing inkjet-printed TFTs that include an ultra-thin polymeric dielectric layer produced by initiated chemical vapor deposition (iCVD) at room temperature and highly purified 99.9% semiconducting carbon nanotubes. Our integrated approach enables the production of flexible logic circuits consisting of CNT-TFTs on a polyethersulfone (PES) substrate that have a high mobility (up to 9.76 cm2 V−1 sec−1), a low operating voltage (less than 4 V), a high current on/off ratio (3 × 104), and a total device yield of 90%. Thus, it should be emphasized that this study delineates a guideline for the feasibility of producing flexible CNT-TFT logic circuits with high performance based on a low-cost and simple fabrication process. PMID:27184121

Logic circuits composed of flexible carbon nanotube thin-film transistor and ultra-thin polymer gate dielectric

NASA Astrophysics Data System (ADS)

Lee, Dongil; Yoon, Jinsu; Lee, Juhee; Lee, Byung-Hyun; Seol, Myeong-Lok; Bae, Hagyoul; Jeon, Seung-Bae; Seong, Hyejeong; Im, Sung Gap; Choi, Sung-Jin; Choi, Yang-Kyu

2016-05-01

Printing electronics has become increasingly prominent in the field of electronic engineering because this method is highly efficient at producing flexible, low-cost and large-scale thin-film transistors. However, TFTs are typically constructed with rigid insulating layers consisting of oxides and nitrides that are brittle and require high processing temperatures, which can cause a number of problems when used in printed flexible TFTs. In this study, we address these issues and demonstrate a method of producing inkjet-printed TFTs that include an ultra-thin polymeric dielectric layer produced by initiated chemical vapor deposition (iCVD) at room temperature and highly purified 99.9% semiconducting carbon nanotubes. Our integrated approach enables the production of flexible logic circuits consisting of CNT-TFTs on a polyethersulfone (PES) substrate that have a high mobility (up to 9.76 cm2 V-1 sec-1), a low operating voltage (less than 4 V), a high current on/off ratio (3 × 104), and a total device yield of 90%. Thus, it should be emphasized that this study delineates a guideline for the feasibility of producing flexible CNT-TFT logic circuits with high performance based on a low-cost and simple fabrication process.

3D Printing of Ball Grid Arrays

NASA Astrophysics Data System (ADS)

Sinha, Shayandev; Hines, Daniel; Dasgupta, Abhijit; Das, Siddhartha

Ball grid arrays (BGA) are interconnects between an integrated circuit (IC) and a printed circuit board (PCB), that are used for surface mounting electronic components. Typically, lead free alloys are used to make solder balls which, after a reflow process, establish a mechanical and electrical connection between the IC and the PCB. High temperature processing is required for most of these alloys leading to thermal shock causing damage to ICs. For producing flexible circuits on a polymer substrate, there is a requirement for low temperature processing capabilities (around 150 C) and for reducing strain from mechanical stresses. Additive manufacturing techniques can provide an alternative methodology for fabricating BGAs as a direct replacement for standard solder bumped BGAs. We have developed aerosol jet (AJ) printing methods to fabricate a polymer bumped BGA. As a demonstration of the process developed, a daisy chain test chip was polymer bumped using an AJ printed ultra violet (UV) curable polymer ink that was then coated with an AJ printed silver nanoparticle laden ink as a conducting layer printed over the polymer bump. The structure for the balls were achieved by printing the polymer ink using a specific toolpath coupled with in-situ UV curing of the polymer which provided good control over the shape, resulting in well-formed spherical bumps on the order of 200 um wide by 200 um tall for this initial demonstration. A detailed discussion of the AJ printing method and results from accelerated life-time testing will be presented

Printed circuit board impedance matching step for microwave (millimeter wave) devices

DOEpatents

Pao, Hsueh-Yuan; Aguirre, Jerardo; Sargis, Paul

2013-10-01

An impedance matching ground plane step, in conjunction with a quarter wave transformer section, in a printed circuit board provides a broadband microwave matching transition from board connectors or other elements that require thin substrates to thick substrate (>quarter wavelength) broadband microwave (millimeter wave) devices. A method of constructing microwave and other high frequency electrical circuits on a substrate of uniform thickness, where the circuit is formed of a plurality of interconnected elements of different impedances that individually require substrates of different thicknesses, by providing a substrate of uniform thickness that is a composite or multilayered substrate; and forming a pattern of intermediate ground planes or impedance matching steps interconnected by vias located under various parts of the circuit where components of different impedances are located so that each part of the circuit has a ground plane substrate thickness that is optimum while the entire circuit is formed on a substrate of uniform thickness.

Progress in 3D Printing of Carbon Materials for Energy-Related Applications.

PubMed

Fu, Kun; Yao, Yonggang; Dai, Jiaqi; Hu, Liangbing

2017-03-01

The additive-manufacturing (AM) technique, known as three-dimensional (3D) printing, has attracted much attention in industry and academia in recent years. 3D printing has been developed for a variety of applications. Printable inks are the most important component for 3D printing, and are related to the materials, the printing method, and the structures of the final 3D-printed products. Carbon materials, due to their good chemical stability and versatile nanostructure, have been widely used in 3D printing for different applications. Good inks are mainly based on volatile solutions having carbon materials as fillers such as graphene oxide (GO), carbon nanotubes (CNT), carbon blacks, and solvent, as well as polymers and other additives. Studies of carbon materials in 3D printing, especially GO-based materials, have been extensively reported for energy-related applications. In these circumstances, understanding the very recent developments of 3D-printed carbon materials and their extended applications to address energy-related challenges and bring new concepts for material designs are becoming urgent and important. Here, recent developments in 3D printing of emerging devices for energy-related applications are reviewed, including energy-storage applications, electronic circuits, and thermal-energy applications at high temperature. To close, a conclusion and outlook are provided, pointing out future designs and developments of 3D-printing technology based on carbon materials for energy-related applications and beyond. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A low-power integrated humidity CMOS sensor by printing-on-chip technology.

PubMed

Lee, Chang-Hung; Chuang, Wen-Yu; Cowan, Melissa A; Wu, Wen-Jung; Lin, Chih-Ting

2014-05-23

A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems.

A Low-Power Integrated Humidity CMOS Sensor by Printing-on-Chip Technology

PubMed Central

Lee, Chang-Hung; Chuang, Wen-Yu; Cowan, Melissa A.; Wu, Wen-Jung; Lin, Chih-Ting

2014-01-01

A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems. PMID:24859027

[Newly leaching method of copper from waste print circuit board using hydrochloric acid/n-butylamine/copper sulfate].

PubMed

Wang, Hong-Yan; Cui, Zhao-Jie; Yao, Ya-Wei

2010-12-01

A newly leaching method of copper from waste print circuit board was established by using hydrochloric acid-n-butylamine-copper sulfate mixed solution. The conditions of leaching were optimized by changing the hydrochloric acid, n-butylamine, copper sulfate,temperature and other conditions using copper as target mimics. The results indicated that copper could be leached completely after 8 h at 50 degrees C, hydrochloric acid concentration of 1.75 mol/L, n-butylamine concentration of 0.25 mol/L, and copper sulfate mass of 0.96 g. Under the conditions, copper leaching rates in waste print circuit board samples was up to 95.31% after 9 h. It has many advantages such as better effects, low cost, mild reaction conditions, leaching solution recycling.

Coaxial connector for use with printed circuit board edge connector

DOEpatents

Howard, Donald R.; MacGill, Robert A.

1989-01-01

A coaxial cable connector for interfacing with an edge connector for a printed circuit board whereby a coaxial cable can be interconnected with a printed circuit board through the edge connector. The coaxial connector includes a body having two leg portions extending from one side for receiving the edge connector therebetween, and a tubular portion extending from an opposing side for receiving a coaxial cable. A cavity within the body receives a lug of the edge connector and the center conductor of the coaxial cable. Adjacent lugs of the edge connector can be bend around the edge connector housing to function as spring-loaded contacts for receiving the coaxial connector. The lugs also function to facilitate shielding of the center conductor where fastened to the edge connector lug.

Fully Printed Stretchable Thin-Film Transistors and Integrated Logic Circuits.

PubMed

Cai, Le; Zhang, Suoming; Miao, Jinshui; Yu, Zhibin; Wang, Chuan

2016-12-27

This paper reports intrinsically stretchable thin-film transistors (TFTs) and integrated logic circuits directly printed on elastomeric polydimethylsiloxane (PDMS) substrates. The printed devices utilize carbon nanotubes and a type of hybrid gate dielectric comprising PDMS and barium titanate (BaTiO 3 ) nanoparticles. The BaTiO 3 /PDMS composite simultaneously provides high dielectric constant, superior stretchability, low leakage, as well as good printability and compatibility with the elastomeric substrate. Both TFTs and logic circuits can be stretched beyond 50% strain along either channel length or channel width directions for thousands of cycles while showing no significant degradation in electrical performance. This work may offer an entry into more sophisticated stretchable electronic systems with monolithically integrated sensors, actuators, and displays, fabricated by scalable and low-cost methods for real life applications.

Printing low-melting-point alloy ink to directly make a solidified circuit or functional device with a heating pen

PubMed Central

Wang, Lei; Liu, Jing

2014-01-01

A new method to directly print out a solidified electronic circuit through low-melting-point metal ink is proposed. A functional pen with heating capability was fabricated. Several typical thermal properties of the alloy ink Bi35In48.6Sn16Zn0.4 were measured and evaluated. Owing to the specifically selected melting point of the ink, which is slightly higher than room temperature, various electronic devices, graphics or circuits can be manufactured in a short period of time and then rapidly solidified by cooling in the surrounding air. The liquid–solid phase change mechanism of the written lines was experimentally characterized using a scanning electron microscope. In order to determine the matching substrate, wettability between the metal ink Bi35In48.6Sn16Zn0.4 and several materials, including mica plate and silicone rubber, was investigated. The resistance–temperature curve of a printed resistor indicated its potential as a temperature control switch. Furthermore, the measured reflection coefficient of a printed double-diamond antenna accords well with the simulated result. With unique merits such as no pollution, no requirement for encapsulation and easy recycling, the present printing approach is an important supplement to current printed electronics and has enormous practical value in the future. PMID:25484611

Printing low-melting-point alloy ink to directly make a solidified circuit or functional device with a heating pen.

PubMed

Wang, Lei; Liu, Jing

2014-12-08

A new method to directly print out a solidified electronic circuit through low-melting-point metal ink is proposed. A functional pen with heating capability was fabricated. Several typical thermal properties of the alloy ink Bi 35 In 48.6 Sn 16 Zn 0.4 were measured and evaluated. Owing to the specifically selected melting point of the ink, which is slightly higher than room temperature, various electronic devices, graphics or circuits can be manufactured in a short period of time and then rapidly solidified by cooling in the surrounding air. The liquid-solid phase change mechanism of the written lines was experimentally characterized using a scanning electron microscope. In order to determine the matching substrate, wettability between the metal ink Bi 35 In 48.6 Sn 16 Zn 0.4 and several materials, including mica plate and silicone rubber, was investigated. The resistance-temperature curve of a printed resistor indicated its potential as a temperature control switch. Furthermore, the measured reflection coefficient of a printed double-diamond antenna accords well with the simulated result. With unique merits such as no pollution, no requirement for encapsulation and easy recycling, the present printing approach is an important supplement to current printed electronics and has enormous practical value in the future.

A study on Aerosol jet printing technology in LED module manufacturing

NASA Astrophysics Data System (ADS)

Rudorfer, Andreas; Tscherner, Martin; Palfinger, Christian; Reil, Frank; Hartmann, Paul; Seferis, Ioannis E.; Zych, Eugeniusz; Wenzl, Franz P.

2016-09-01

State of the art fabrication of LED modules based on chip-on-board (COB) technology comprises some shortcomings both with respect to the manufacturing process itself but also with regard to potential sources of failures and manufacturing impreciseness. One promising alternative is additive manufacturing, a technology which has gained a lot of attention during the last years due to its materials and cost saving capabilities. Especially direct-write technologies like Aerosol jet printing have demonstrated advantages compared to other technological approaches when printing high precision layers or high precision electronic circuits on substrates which, as an additional advantage, also can be flexible and 3D shaped. Based on test samples and test structures manufactured by Aerosol jet printing technology, in this context we discuss the potentials of additive manufacturing in various aspects of LED module fabrication, ranging from the deposition of the die-attach material, wire bond replacement by printed electrical connects as well as aspects of high-precision phosphor layer deposition for color conversion and white light generation.

Making Complex Electrically Conductive Patterns on Cloth

NASA Technical Reports Server (NTRS)

Chu, Andrew; Fink, Patrick W.; Dobbins, Justin A.; Lin, Greg Y.; Scully, Robert C.; Trevino, Robert

2008-01-01

A method for automated fabrication of flexible, electrically conductive patterns on cloth substrates has been demonstrated. Products developed using this method, or related prior methods, are instances of a technology known as 'e-textiles,' in which electrically conductive patterns ar formed in, and on, textiles. For many applications, including high-speed digital circuits, antennas, and radio frequency (RF) circuits, an e-textile method should be capable of providing high surface conductivity, tight tolerances for control of characteristic impedances, and geometrically complex conductive patterns. Unlike prior methods, the present method satisfies all three of these criteria. Typical patterns can include such circuit structures as RF transmission lines, antennas, filters, and other conductive patterns equivalent to those of conventional printed circuits. The present method overcomes the limitations of the prior methods for forming the equivalent of printed circuits on cloth. A typical fabrication process according to the present method involves selecting the appropriate conductive and non-conductive fabric layers to build the e-textile circuit. The present method uses commercially available woven conductive cloth with established surface conductivity specifications. Dielectric constant, loss tangent, and thickness are some of the parameters to be considered for the non-conductive fabric layers. The circuit design of the conductive woven fabric is secured onto a non-conductive fabric layer using sewing, embroidery, and/or adhesive means. The portion of the conductive fabric that is not part of the circuit is next cut from the desired circuit using an automated machine such as a printed-circuit-board milling machine or a laser cutting machine. Fiducials can be used to align the circuit and the cutting machine. Multilayer circuits can be built starting with the inner layer and using conductive thread to make electrical connections between layers.

Fully Solution-Processable Fabrication of Multi-Layered Circuits on a Flexible Substrate Using Laser Processing

PubMed Central

Ji, Seok Young; Choi, Wonsuk; Jeon, Jin-Woo; Chang, Won Seok

2018-01-01

The development of printing technologies has enabled the realization of electric circuit fabrication on a flexible substrate. However, the current technique remains restricted to single-layer patterning. In this paper, we demonstrate a fully solution-processable patterning approach for multi-layer circuits using a combined method of laser sintering and ablation. Selective laser sintering of silver (Ag) nanoparticle-based ink is applied to make conductive patterns on a heat-sensitive substrate and insulating layer. The laser beam path and irradiation fluence are controlled to create circuit patterns for flexible electronics. Microvia drilling using femtosecond laser through the polyvinylphenol-film insulating layer by laser ablation, as well as sequential coating of Ag ink and laser sintering, achieves an interlayer interconnection between multi-layer circuits. The dimension of microvia is determined by a sophisticated adjustment of the laser focal position and intensity. Based on these methods, a flexible electronic circuit with chip-size-package light-emitting diodes was successfully fabricated and demonstrated to have functional operations. PMID:29425144

75 FR 47609 - U.S. Customs and Border Protection; Notice of Issuance of Final Determination Concerning a...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-06

... Denver, Colorado. Communication Manager is designed to run on a variety of Linux-based media servers.... Some servers are in the form of blades. These are cards (similar to printed circuit cards with...

Fabric-based active electrode design and fabrication for health monitoring clothing.

PubMed

Merritt, Carey R; Nagle, H Troy; Grant, Edward

2009-03-01

In this paper, two versions of fabric-based active electrodes are presented to provide a wearable solution for ECG monitoring clothing. The first version of active electrode involved direct attachment of surface-mountable components to a textile screen-printed circuit using polymer thick film techniques. The second version involved attaching a much smaller, thinner, and less obtrusive interposer containing the active electrode circuitry to a simplified textile circuit. These designs explored techniques for electronic textile interconnection, chip attachment to textiles, and packaging of circuits on textiles for durability. The results from ECG tests indicate that the performance of each active electrode is comparable to commercial Ag/AgCl electrodes. The interposer-based active electrodes survived a five-cycle washing test while maintaining good signal integrity.

Chemically programmed ink-jet printed resistive WORM memory array and readout circuit

NASA Astrophysics Data System (ADS)

Andersson, H.; Manuilskiy, A.; Sidén, J.; Gao, J.; Hummelgård, M.; Kunninmel, G. V.; Nilsson, H.-E.

2014-09-01

In this paper an ink-jet printed write once read many (WORM) resistive memory fabricated on paper substrate is presented. The memory elements are programmed for different resistance states by printing triethylene glycol monoethyl ether on the substrate before the actual memory element is printed using silver nano particle ink. The resistance is thus able to be set to a broad range of values without changing the geometry of the elements. A memory card consisting of 16 elements is manufactured for which the elements are each programmed to one of four defined logic levels, providing a total of 4294 967 296 unique possible combinations. Using a readout circuit, originally developed for resistive sensors to avoid crosstalk between elements, a memory card reader is manufactured that is able to read the values of the memory card and transfer the data to a PC. Such printed memory cards can be used in various applications.

Surface and Electrical Characterization of Ag/AgCl Pseudo-Reference Electrodes Manufactured with Commercially Available PCB Technologies

PubMed Central

Moschou, Despina; Trantidou, Tatiana; Regoutz, Anna; Carta, Daniela; Morgan, Hywel; Prodromakis, Themistoklis

2015-01-01

Lab-on-Chip is a technology that could potentially revolutionize medical Point-of-Care diagnostics. Considerable research effort is focused towards innovating production technologies that will make commercial upscaling financially viable. Printed circuit board manufacturing techniques offer several prospects in this field. Here, we present a novel approach to manufacturing Printed Circuit Board (PCB)-based Ag/AgCl reference electrodes, an essential component of biosensors. Our prototypes were characterized both structurally and electrically. Scanning Electron Microscopy (SEM) and X-Ray Photoelectron Spectroscopy (XPS) were employed to evaluate the electrode surface characteristics. Electrical characterization was performed to determine stability and pH dependency. Finally, we demonstrate utilization along with PCB pH sensors, as a step towards a fully integrated PCB platform, comparing performance with discrete commercial reference electrodes. PMID:26213940

Alumina Based 500 C Electronic Packaging Systems and Future Development

NASA Technical Reports Server (NTRS)

Chen, Liang-Yu

2012-01-01

NASA space and aeronautical missions for probing the inner solar planets as well as for in situ monitoring and control of next-generation aeronautical engines require high-temperature environment operable sensors and electronics. A 96% aluminum oxide and Au thick-film metallization based packaging system including chip-level packages, printed circuit board, and edge-connector is in development for high temperature SiC electronics. An electronic packaging system based on this material system was successfully tested and demonstrated with SiC electronics at 500 C for over 10,000 hours in laboratory conditions previously. In addition to the tests in laboratory environments, this packaging system has more recently been tested with a SiC junction field effect transistor (JFET) on low earth orbit through the NASA Materials on the International Space Station Experiment 7 (MISSE7). A SiC JFET with a packaging system composed of a 96% alumina chip-level package and an alumina printed circuit board mounted on a data acquisition circuit board was launched as a part of the MISSE7 suite to International Space Station via a Shuttle mission and tested on the orbit for eighteen months. A summary of results of tests in both laboratory and space environments will be presented. The future development of alumina based high temperature packaging using co-fired material systems for improved performance at high temperature and more feasible mass production will also be discussed.

Spatial Control of Bacteria Using Screen Printing

PubMed Central

Moon, Soonhee; Fritz, Ian L.; Singer, Zakary S.

2016-01-01

Abstract Synthetic biology has led to advances in both our understanding and engineering of genetic circuits that affect spatial and temporal behaviors in living cells. A growing array of native and synthetic circuits such as oscillators, pattern generators, and cell–cell communication systems has been studied, which exhibit spatiotemporal properties. To better understand the design principles of these genetic circuits, there is a need for versatile and precise methods for patterning cell populations in various configurations. In this study, we develop a screen printing methodology to pattern bacteria on agar, glass, and paper surfaces. Initially, we tested three biocompatible resuspension media with appropriate rheological properties for screen printing. Using microscopy, we characterized the resolution and bleed of bacteria screen prints on agar and glass surfaces, obtaining resolutions as low as 188 μm. Next, we engineered bacterial strains producing visible chromoproteins analogous to the cyan, magenta, and yellow subtractive color system for the creation of multicolored bacteria images. Using this system, we printed distinct populations in overlapping or interlocking designs on both paper and agar substrates. These proof-of-principle experiments demonstrated how the screen printing method could be used to study microbial community interactions and pattern formation of biofilms at submillimeter length scales. Overall, our approach allows for rapid and precise prototyping of patterned bacteria species that will be useful in the understanding and engineering of spatiotemporal behaviors in microbial communities. PMID:29577061

Capacitive charge generation apparatus and method for testing circuits

DOEpatents

Cole, E.I. Jr.; Peterson, K.A.; Barton, D.L.

1998-07-14

An electron beam apparatus and method for testing a circuit are disclosed. The electron beam apparatus comprises an electron beam incident on an outer surface of an insulating layer overlying one or more electrical conductors of the circuit for generating a time varying or alternating current electrical potential on the surface; and a measurement unit connected to the circuit for measuring an electrical signal capacitively coupled to the electrical conductors to identify and map a conduction state of each of the electrical conductors, with or without an electrical bias signal being applied to the circuit. The electron beam apparatus can further include a secondary electron detector for forming a secondary electron image for registration with a map of the conduction state of the electrical conductors. The apparatus and method are useful for failure analysis or qualification testing to determine the presence of any open-circuits or short-circuits, and to verify the continuity or integrity of electrical conductors buried below an insulating layer thickness of 1-100 {micro}m or more without damaging or breaking down the insulating layer. The types of electrical circuits that can be tested include integrated circuits, multi-chip modules, printed circuit boards and flexible printed circuits. 7 figs.

Capacitive charge generation apparatus and method for testing circuits

DOEpatents

Cole, Jr., Edward I.; Peterson, Kenneth A.; Barton, Daniel L.

1998-01-01

An electron beam apparatus and method for testing a circuit. The electron beam apparatus comprises an electron beam incident on an outer surface of an insulating layer overlying one or more electrical conductors of the circuit for generating a time varying or alternating current electrical potential on the surface; and a measurement unit connected to the circuit for measuring an electrical signal capacitively coupled to the electrical conductors to identify and map a conduction state of each of the electrical conductors, with or without an electrical bias signal being applied to the circuit. The electron beam apparatus can further include a secondary electron detector for forming a secondary electron image for registration with a map of the conduction state of the electrical conductors. The apparatus and method are useful for failure analysis or qualification testing to determine the presence of any open-circuits or short-circuits, and to verify the continuity or integrity of electrical conductors buried below an insulating layer thickness of 1-100 .mu.m or more without damaging or breaking down the insulating layer. The types of electrical circuits that can be tested include integrated circuits, multi-chip modules, printed circuit boards and flexible printed circuits.

Fabrication Methods and Performance of Low-Permeability Microfluidic Components for a Miniaturized Wearable Drug Delivery System

PubMed Central

Mescher, Mark J.; Swan, Erin E. Leary; Fiering, Jason; Holmboe, Maria E.; Sewell, William F.; Kujawa, Sharon G.; McKenna, Michael J.; Borenstein, Jeffrey T.

2010-01-01

In this paper, we describe low-permeability components of a microfluidic drug delivery system fabricated with versatile micromilling and lamination techniques. The fabrication process uses laminate sheets which are machined using XY milling tables commonly used in the printed-circuit industry. This adaptable platform for polymer microfluidics readily accommodates integration with silicon-based sensors, printed-circuit, and surface-mount technologies. We have used these methods to build components used in a wearable liquid-drug delivery system for in vivo studies. The design, fabrication, and performance of membrane-based fluidic capacitors and manual screw valves provide detailed examples of the capability and limitations of the fabrication method. We demonstrate fluidic capacitances ranging from 0.015 to 0.15 μL/kPa, screw valves with on/off flow ratios greater than 38 000, and a 45× reduction in the aqueous fluid loss rate to the ambient due to permeation through a silicone diaphragm layer. PMID:20852729

Toxic heavy metal capture using a novel electronic waste-based material-mechanism, modeling and comparison.

PubMed

Hadi, Pejman; Barford, John; McKay, Gordon

2013-08-06

In the modern communication era, the disposal of printed circuit boards is ecologically of dire concern on a global scale. The two prevalent methods applied for the disposal of this waste are either incineration or landfilling both of which are viewed with skepticism due to their negative environmental impact. Activation of the nonmetallic fraction of this waste leads to the development of a mesoporous material with highly functional groups which can potentially be applied for heavy metal uptake. The removal of copper, lead, and zinc was studied employing a cost-effective novel adsorbent based on waste printed circuit boards. The results indicate that the modification of the original e-waste material has a considerable effect on its surface area enhancement. Adsorption experiments revealed that the modified novel material had uptake capacities of 2.9 mmol Cu, 3.4 mmol Pb, and 2.0 mmol Zn per each gram of the adsorbent which are significantly higher values than its commercial counterparts used in industry.

Mineralogical analysis of dust collected from typical recycling line of waste printed circuit boards.

PubMed

Wang, Fangfang; Zhao, Yuemin; Zhang, Tao; Duan, Chenlong; Wang, Lizhang

2015-09-01

As dust is one of the byproducts originating in the mechanical recycling process of waste printed circuit boards such as crushing and separating, from the viewpoints of resource reuse and environmental protection, an effective recycling method to recover valuable materials from this kind of dust is in urgent need. In this paper, detailed mineralogical analysis on the dust collected from a typical recycling line of waste printed circuit boards is investigated by coupling several analytical techniques. The results demonstrate that there are 73.1wt.% organic matters, 4.65wt.% Al, 4.55wt.% Fe, 2.67wt.% Cu and 1.06wt.% Pb in the dust, which reveals the dust is worthy of reuse and harmful to environment. The concentration ratios of Fe, Mn and Zn can reach 12.35, 12.33 and 6.67 respectively by magnetic separation. The yield of dust in each size fraction is nonuniform, while the yield of -0.75mm size fraction is up to 51.15wt.%; as the particle size decreases, the content of liberated metals and magnetic materials increase, and metals are mainly in elemental forms. The F, Cl and Br elements combing to C in the dust would make thermal treatment dangerous to the environment. Based on these results, a flowsheet to recycle the dust is proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cooling/grounding mount for hybrid circuits

NASA Technical Reports Server (NTRS)

Bagstad, B.; Estrada, R.; Mandel, H.

1981-01-01

Extremely short input and output connections, adequate grounding, and efficient heat removal for hybrid integrated circuits are possible with mounting. Rectangular clamp holds hybrid on printed-circuit board, in contact with heat-conductive ground plate. Clamp is attached to ground plane by bolts.

Metals Recovery from Artificial Ore in Case of Printed Circuit Boards, Using Plasmatron Plasma Reactor

PubMed Central

Szałatkiewicz, Jakub

2016-01-01

This paper presents the investigation of metals production form artificial ore, which consists of printed circuit board (PCB) waste, processed in plasmatron plasma reactor. A test setup was designed and built that enabled research of plasma processing of PCB waste of more than 700 kg/day scale. The designed plasma process is presented and discussed. The process in tests consumed 2 kWh/kg of processed waste. Investigation of the process products is presented with their elemental analyses of metals and slag. The average recovery of metals in presented experiments is 76%. Metals recovered include: Ag, Au, Pd, Cu, Sn, Pb, and others. The chosen process parameters are presented: energy consumption, throughput, process temperatures, and air consumption. Presented technology allows processing of variable and hard-to-process printed circuit board waste that can reach up to 100% of the input mass. PMID:28773804

Metals Recovery from Artificial Ore in Case of Printed Circuit Boards, Using Plasmatron Plasma Reactor.

PubMed

Szałatkiewicz, Jakub

2016-08-10

This paper presents the investigation of metals production form artificial ore, which consists of printed circuit board (PCB) waste, processed in plasmatron plasma reactor. A test setup was designed and built that enabled research of plasma processing of PCB waste of more than 700 kg/day scale. The designed plasma process is presented and discussed. The process in tests consumed 2 kWh/kg of processed waste. Investigation of the process products is presented with their elemental analyses of metals and slag. The average recovery of metals in presented experiments is 76%. Metals recovered include: Ag, Au, Pd, Cu, Sn, Pb, and others. The chosen process parameters are presented: energy consumption, throughput, process temperatures, and air consumption. Presented technology allows processing of variable and hard-to-process printed circuit board waste that can reach up to 100% of the input mass.

Packaging Of Control Circuits In A Robot Arm

NASA Technical Reports Server (NTRS)

Kast, William

1994-01-01

Packaging system houses and connects control circuitry mounted on circuit boards within shoulder, upper section, and lower section of seven-degree-of-freedom robot arm. Has modular design that incorporates surface-mount technology, multilayer circuit boards, large-scale integrated circuits, and multi-layer flat cables between sections for compactness. Three sections of robot arm contain circuit modules in form of stardardized circuit boards. Each module contains two printed-circuit cards, one of each face.

Personal electronics printing via tapping mode composite liquid metal ink delivery and adhesion mechanism

NASA Astrophysics Data System (ADS)

Zheng, Yi; He, Zhi-Zhu; Yang, Jun; Liu, Jing

2014-04-01

Printed electronics is becoming increasingly important in a variety of newly emerging areas. However, restricted to the rather limited conductive inks and available printing strategies, the current electronics manufacture is usually confined to industry level. Here, we show a highly cost-effective and entirely automatic printing way towards personal electronics making, through introducing a tapping-mode composite fluid delivery system. Fundamental mechanisms regarding the reliable printing, transfer and adhesion of the liquid metal inks on the substrate were disclosed through systematic theoretical interpretation and experimental measurements. With this liquid metal printer, a series of representative electronic patterns spanning from single wires to desired complex configurations such as integrated circuit (IC), printed-circuits-on-board (PCB), electronic paintings, or more do-it-yourself (DIY) devices, were demonstrated to be printed out with high precision in a moment. And the total machine cost already reached personally affordable price. This is hard to achieve by a conventional PCB technology which generally takes long time and is material, water and energy consuming, while the existing printed electronics is still far away from the real direct printing goal. The present work opens the way for large scale personal electronics manufacture and is expected to generate important value for the coming society.

Personal electronics printing via tapping mode composite liquid metal ink delivery and adhesion mechanism.

PubMed

Zheng, Yi; He, Zhi-Zhu; Yang, Jun; Liu, Jing

2014-04-04

Printed electronics is becoming increasingly important in a variety of newly emerging areas. However, restricted to the rather limited conductive inks and available printing strategies, the current electronics manufacture is usually confined to industry level. Here, we show a highly cost-effective and entirely automatic printing way towards personal electronics making, through introducing a tapping-mode composite fluid delivery system. Fundamental mechanisms regarding the reliable printing, transfer and adhesion of the liquid metal inks on the substrate were disclosed through systematic theoretical interpretation and experimental measurements. With this liquid metal printer, a series of representative electronic patterns spanning from single wires to desired complex configurations such as integrated circuit (IC), printed-circuits-on-board (PCB), electronic paintings, or more do-it-yourself (DIY) devices, were demonstrated to be printed out with high precision in a moment. And the total machine cost already reached personally affordable price. This is hard to achieve by a conventional PCB technology which generally takes long time and is material, water and energy consuming, while the existing printed electronics is still far away from the real direct printing goal. The present work opens the way for large scale personal electronics manufacture and is expected to generate important value for the coming society.

Personal electronics printing via tapping mode composite liquid metal ink delivery and adhesion mechanism

PubMed Central

Zheng, Yi; He, Zhi-Zhu; Yang, Jun; Liu, Jing

2014-01-01

Printed electronics is becoming increasingly important in a variety of newly emerging areas. However, restricted to the rather limited conductive inks and available printing strategies, the current electronics manufacture is usually confined to industry level. Here, we show a highly cost-effective and entirely automatic printing way towards personal electronics making, through introducing a tapping-mode composite fluid delivery system. Fundamental mechanisms regarding the reliable printing, transfer and adhesion of the liquid metal inks on the substrate were disclosed through systematic theoretical interpretation and experimental measurements. With this liquid metal printer, a series of representative electronic patterns spanning from single wires to desired complex configurations such as integrated circuit (IC), printed-circuits-on-board (PCB), electronic paintings, or more do-it-yourself (DIY) devices, were demonstrated to be printed out with high precision in a moment. And the total machine cost already reached personally affordable price. This is hard to achieve by a conventional PCB technology which generally takes long time and is material, water and energy consuming, while the existing printed electronics is still far away from the real direct printing goal. The present work opens the way for large scale personal electronics manufacture and is expected to generate important value for the coming society. PMID:24699375

Fully inkjet-printed two-dimensional material field-effect heterojunctions for wearable and textile electronics.

PubMed

Carey, Tian; Cacovich, Stefania; Divitini, Giorgio; Ren, Jiesheng; Mansouri, Aida; Kim, Jong M; Wang, Chaoxia; Ducati, Caterina; Sordan, Roman; Torrisi, Felice

2017-10-31

Fully printed wearable electronics based on two-dimensional (2D) material heterojunction structures also known as heterostructures, such as field-effect transistors, require robust and reproducible printed multi-layer stacks consisting of active channel, dielectric and conductive contact layers. Solution processing of graphite and other layered materials provides low-cost inks enabling printed electronic devices, for example by inkjet printing. However, the limited quality of the 2D-material inks, the complexity of the layered arrangement, and the lack of a dielectric 2D-material ink able to operate at room temperature, under strain and after several washing cycles has impeded the fabrication of electronic devices on textile with fully printed 2D heterostructures. Here we demonstrate fully inkjet-printed 2D-material active heterostructures with graphene and hexagonal-boron nitride (h-BN) inks, and use them to fabricate all inkjet-printed flexible and washable field-effect transistors on textile, reaching a field-effect mobility of ~91 cm 2  V -1  s -1 , at low voltage (<5 V). This enables fully inkjet-printed electronic circuits, such as reprogrammable volatile memory cells, complementary inverters and OR logic gates.

Evaluation of test equipment for the detection of contamination on electronic circuits

NASA Astrophysics Data System (ADS)

Bergendahl, C. G.; Dunn, B. D.

1984-08-01

The reproducibility, sensitivity and ease of operation of test equipment for the detection of ionizable contaminants on the surface of printed circuit assemblies were assessed. The characteristics of the test equipment are described. Soldering fluxes were chosen as contaminants and were applied in controlled amounts to printed-circuit board assemblies possessing two different component populations. Results show that the relationship between equipment readings varies with flux type. Each kind of test equipment gives a good measure of board cleanliness, although reservations exist concerning the interpretation of such results. A test method for the analysis of total (organic and inorganic) halides in solder fluxes is presented.

77 FR 2957 - Application for Manufacturing Authority, Liberty Pumps, Inc. (Submersible and Water Pumps...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-20

..., mechanical seals, electric motors, transformers, capacitors, switches, electronic components, integrated circuits, process controllers, printed circuit assemblies, electrical components, and measuring instruments...

Effect of Ground Layer Patterns with Slits on Conducted Noise Currents from Printed Circuit Board

NASA Astrophysics Data System (ADS)

Maeno, Tsuyoshi; Unou, Takanori; Ichikawa, Kouji; Fujiwara, Osamu

Electromagnetic disturbances for vehicle-mounted radios can be caused by conducted noise currents that flows out from electronic equipment for vehicles to wire-harnesses. In this paper, for reducing the conducted noise currents from electronic equipment for vehicles, we made a simulation and experiment on how ground patterns affect the noise currents from three-layer printed circuit boards (PCBs) with slit-types and plane-type ground patterns. As a result, we could confirm that slits on a ground pattern allow conducted noise currents to flow out from PCBs to wire-harnesses. For the PCBs with plane-type ground and one of three slit-type patterns, on the other hand, both the simulation and examination showed that resonance phenomena occur at unexpected low-frequencies. A circuit analysis revealed that the above phenomena can be caused by the imbalance of a bridge circuit consisting of the trace circuits on the PCB.

Thermal and Electrical Investigation of Conductive Polylactic Acid Based Filaments

NASA Astrophysics Data System (ADS)

Dobre, R. A.; Marcu, A. E.; Drumea, A.; Vlădescu, M.

2018-06-01

Printed electronics gain momentum as the involved technologies become affordable. The ability to shape electrostatic dissipative materials in almost any form is useful. The idea to use a general-purpose 3D printer to manufacture the electrical interconnections for a circuit is very attractive. The advantage of using a 3D printed structure over other technologies are mainly the lower price, less requirements concerning storage and use conditions, and the capability to build thicker traces while maintaining flexibility. The main element allowing this to happen is a printing filament with conductive properties. The paper shows the experiments that were performed to determine the thermal and electrical properties of polylactic acid (PLA) based ESD dissipative filament. Quantitative results regarding the thermal behavior of the DC resistance and the variation of the equivalent parallel impedance model parameters (losses resistance, capacitance, impedance magnitude and phase angle) with frequency are shown.. Using these results, new applications like printed temperature sensors can be imagined.

Comparative analysis of single-walled and multi-walled carbon nanotubes for electrochemical sensing of glucose on gold printed circuit boards.

PubMed

Alhans, Ruby; Singh, Anukriti; Singhal, Chaitali; Narang, Jagriti; Wadhwa, Shikha; Mathur, Ashish

2018-09-01

In the present work, a comparative study was performed between single-walled carbon nanotubes and multi-walled carbon nanotubes coated gold printed circuit board electrodes for glucose detection. Various characterization techniques were demonstrated in order to compare the modified electrodes viz. cyclic voltammetry, electrochemical impedance spectroscopy and chrono-amperometry. Results revealed that single-walled carbon nanotubes outperformed multi-walled carbon nanotubes and proved to be a better sensing interface for glucose detection. The single-walled carbon nanotubes coated gold printed circuit board electrodes showed a wide linear sensing range (1 mM to 100 mM) with detection limit of 0.1 mM with response time of 5 s while multi-walled carbon nanotubes coated printed circuit board gold electrodes showed linear sensing range (1 mM to 100 mM) with detection limit of 0.1 mM with response time of 5 s. This work provided low cost sensors with enhanced sensitivity, fast response time and reliable results for glucose detection which increased the affordability of such tests in remote areas. In addition, the comparative results confirmed that single-walled carbon nanotubes modified electrodes can be exploited for better amplification signal as compared to multi-walled carbon nanotubes. Copyright © 2018. Published by Elsevier B.V.

Tailored benzoxazines as novel resin systems for printed circuit boards in high temperature e-mobility applications

NASA Astrophysics Data System (ADS)

Troeger, K.; Darka, R. Khanpour; Neumeyer, T.; Altstaedt, V.

2014-05-01

This study focuses on the development of Bisphenol-F-benzoxazine resins blended with different ratios of a trifunctional epoxy resin suitable as matrix for substrates for high temperature printed circuit board (HT-PCB) applications. With the benzoxazine blends glass transition temperatures of more than 190 °C could be achieved in combination with a coefficient of thermal expansion in thickness direction (z-CTE) of less than 60 ppm/K without adding any fillers. This shows the high potential of the benzoxazine-epoxy blend systems as substrate materials for HT-PCBs. To understand the thermal behavior of the different formulations, the apparent crosslink density was calculated based on data from Dynamic Mechanical Analysis. Laminates in laboratory scale were prepared and characterized to demonstrate the transformation of the neat resin properties into real electronic substrate properties. The produced laminates exhibit a z-CTE below 40 ppm/K.

Tailored benzoxazines as novel resin systems for printed circuit boards in high temperature e-mobility applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Troeger, K., E-mail: altstaedt@uni-bayreuth.de; Darka, R. Khanpour, E-mail: altstaedt@uni-bayreuth.de; Neumeyer, T., E-mail: altstaedt@uni-bayreuth.de

2014-05-15

This study focuses on the development of Bisphenol-F-benzoxazine resins blended with different ratios of a trifunctional epoxy resin suitable as matrix for substrates for high temperature printed circuit board (HT-PCB) applications. With the benzoxazine blends glass transition temperatures of more than 190 °C could be achieved in combination with a coefficient of thermal expansion in thickness direction (z-CTE) of less than 60 ppm/K without adding any fillers. This shows the high potential of the benzoxazine-epoxy blend systems as substrate materials for HT-PCBs. To understand the thermal behavior of the different formulations, the apparent crosslink density was calculated based on datamore » from Dynamic Mechanical Analysis. Laminates in laboratory scale were prepared and characterized to demonstrate the transformation of the neat resin properties into real electronic substrate properties. The produced laminates exhibit a z-CTE below 40 ppm/K.« less

Waste Printed Circuit Board (PCB) Recycling Techniques.

PubMed

Ning, Chao; Lin, Carol Sze Ki; Hui, David Chi Wai; McKay, Gordon

2017-04-01

With the development of technologies and the change of consumer attitudes, the amount of waste electrical and electronic equipment (WEEE) is increasing annually. As the core part of WEEE, the waste printed circuit board (WPCB) is a dangerous waste but at the same time a rich resource for various kinds of materials. In this work, various WPCB treatment methods as well as WPCB recycling techniques divided into direct treatment (landfill and incineration), primitive recycling technology (pyrometallurgy, hydrometallurgy, biometallurgy and primitive full recovery of NMF-non metallic fraction), and advanced recycling technology (mechanical separation, direct use and modification of NMF) are reviewed and analyzed based on their advantages and disadvantages. Also, the evaluation criteria are discussed including economic, environmental, and gate-to-market ability. This review indicates the future research direction of WPCB recycling should focus on a combination of several techniques or in series recycling to maximize the benefits of process.

Ab initio surface properties of Ag-Sn alloys: implications for lead-free soldering.

PubMed

Saleh, Gabriele; Xu, Chen; Sanvito, Stefano

2018-02-07

Ag and Sn are the major components of solder alloys adopted to assemble printed circuit boards. The qualities that make them the alloys of choice for the modern electronic industry are related to their physical and chemical properties. For corrosion resistance and solderability, surface properties are particularly important. Yet, atomic-level information about the surfaces of these alloys is not known. Here we fill this gap by presenting an extensive ab initio investigation of composition, energetics, structure and reactivity of Ag-Sn alloy surfaces. The structure and stability of various surfaces is evaluated, and the main factors determining the energetics of surface formation are uncovered. Oxygen and sulphur chemisorptions are studied and discussed in the framework of corrosion tendency, an important issue for printed circuit boards. Adsorption energy trends are rationalized based on the analysis of structural and electronic features.

Design of micro-ring optical sensors and circuits for integration on optical printed circuit boards (O-PCBs)

NASA Astrophysics Data System (ADS)

Lee, El-Hang; Lee, Hyun S.; Lee, S. G.; O, B. H.; Park, S. G.; Kim, K. H.

2007-05-01

We report on the design of micro-ring resonator optical sensors for integration on what we call optical printed circuit boards (O-PCBs). The objective is to realize application-specific O-PCBs, either on hard board or on flexible board, by integrating micro/nano-scale optical sensors for compact, light-weight, low-energy, high-speed, intelligent, and environmentally friendly processing of information. The O-PCBs consist of two-dimensional planar arrays of micro/nano-scale optical wires, circuits and devices that are interconnected and integrated to perform the functions of sensing and then storing, transporting, processing, switching, routing and distributing optical signals that have been collected by means of sensors. For fabrication, the polymer and organic optical wires and waveguides are first fabricated on a board and are used to interconnect and integrate sensors and other micro/ nano-scale photonic devices. Here, in our study, we focus on the sensors based on the micro-ring structures. We designed bio-sensors using silicon based micro-ring resonator. We investigate the characteristics such as sensitivity and selectivity (or quality factor) of micro-ring resonator for their use in bio-sensing application. We performed simulation studies on the quality factor of micro-ring resonators by varying the radius of the ring resonators and the separation between adjacent waveguides. We introduce the effective coupling coefficient as a realistic value to describe the strength of the coupling in micro-ring resonators.

Integrated digital printing of flexible circuits for wireless sensing (Conference Presentation)

NASA Astrophysics Data System (ADS)

Mei, Ping; Whiting, Gregory L.; Schwartz, David E.; Ng, Tse Nga; Krusor, Brent S.; Ready, Steve E.; Daniel, George; Veres, Janos; Street, Bob

2016-09-01

Wireless sensing has broad applications in a wide variety of fields such as infrastructure monitoring, chemistry, environmental engineering and cold supply chain management. Further development of sensing systems will focus on achieving light weight, flexibility, low power consumption and low cost. Fully printed electronics provide excellent flexibility and customizability, as well as the potential for low cost and large area applications, but lack solutions for high-density, high-performance circuitry. Conventional electronics mounted on flexible printed circuit boards provide high performance but are not digitally fabricated or readily customizable. Incorporation of small silicon dies or packaged chips into a printed platform enables high performance without compromising flexibility or cost. At PARC, we combine high functionality c-Si CMOS and digitally printed components and interconnects to create an integrated platform that can read and process multiple discrete sensors. Our approach facilitates customization to a wide variety of sensors and user interfaces suitable for a broad range of applications including remote monitoring of health, structures and environment. This talk will describe several examples of printed wireless sensing systems. The technologies required for these sensor systems are a mix of novel sensors, printing processes, conventional microchips, flexible substrates and energy harvesting power solutions.

Chemical and biological processes for multi-metal extraction from waste printed circuit boards of computers and mobile phones.

PubMed

Shah, Monal B; Tipre, Devayani R; Dave, Shailesh R

2014-11-01

E-waste printed circuit boards (PCB) of computers, mobile-phones, televisions, LX (LongXiang) PCB in LED lights and bulbs, and tube-lights were crushed to ≥250 µm particle size and 16 different metals were analysed. A comparative study has been carried out to evaluate the extraction of Cu-Zn-Ni from computer printed circuit boards (c-PCB) and mobile-phone printed circuit boards (m-PCB) by chemical and biological methods. Chemical process showed the extraction of Cu-Zn-Ni by ferric sulphate was best among the studied chemical lixiviants. Bioleaching experiments were carried out with the iron oxidising consortium, which showed that when E-waste and inoculum were added simultaneously in the medium (one-step process); 60.33% and 87.50% Cu, 75.67% and 85.67% Zn and 71.09% and 81.87% Ni were extracted from 10 g L(-1) of c-PCB and m-PCB, respectively, within 10-15 days of reaction time. Whereas, E-waste added after the complete oxidation of Fe(2+) to Fe(3+) iron containing medium (two-step process) showed 85.26% and 99.99% Cu, 96.75% and 99.49% Zn and 93.23% and 84.21% Ni extraction from c-PCB and m-PCB, respectively, only in 6-8 days. Influence of varying biogenerated Fe(3+) and c-PCB concentrations showed that 16.5 g L(-1) of Fe(3+) iron was optimum up to 100 g L(-1) of c-PCB. Changes in pH, acid consumed and redox potential during the process were also studied. The present study shows the ability of an eco-friendly process for the recovery of multi-metals from E-waste even at 100 g L(-1) printed circuit boards concentration. © The Author(s) 2014.

Screen printed passive components for flexible power electronics

NASA Astrophysics Data System (ADS)

Ostfeld, Aminy E.; Deckman, Igal; Gaikwad, Abhinav M.; Lochner, Claire M.; Arias, Ana C.

2015-10-01

Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components—inductors, capacitors, and resistors—perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application.

Screen printed passive components for flexible power electronics

PubMed Central

Ostfeld, Aminy E.; Deckman, Igal; Gaikwad, Abhinav M.; Lochner, Claire M.; Arias, Ana C.

2015-01-01

Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components—inductors, capacitors, and resistors—perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application. PMID:26514331

Screen printed passive components for flexible power electronics.

PubMed

Ostfeld, Aminy E; Deckman, Igal; Gaikwad, Abhinav M; Lochner, Claire M; Arias, Ana C

2015-10-30

Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components-inductors, capacitors, and resistors-perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application.

Reducing Printed Circuit Board Emissions with Low-Noise Design Practices

NASA Technical Reports Server (NTRS)

Bradley, Arthur T.; Fowler, Jennifer; Yavoich, Brian J.; Jennings, Stephen A.

2012-01-01

This paper presents the results of an experiment designed to determine the effectiveness of adopting several low-noise printed circuit board (PCB) design practices. Two boards were designed and fabricated, each consisting of identical mixed signal circuitry. Several important differences were introduced between the board layouts: one board was constructed using recommended low-noise practices and the other constructed without such attention. The emissions from the two boards were then measured and compared, demonstrating an improvement in radiated emissions of up to 22 dB.

Modular chassis simplifies packaging and interconnecting of circuit boards

NASA Technical Reports Server (NTRS)

Arens, W. E.; Boline, K. G.

1964-01-01

A system of modular chassis structures has simplified the design for mounting a number of printed circuit boards. This design is structurally adaptable to computer and industrial control system applications.

Learning high-quality soldering

NASA Technical Reports Server (NTRS)

Read, W. S.

1981-01-01

Soldering techniques for high-reliability electronic equipment are taught in 5 day course at NASA's Jet Propulsion Laboratory. Topic covered include new circuit assembly, printed-wiring board reworking, circuit changes, wire routing, and component installation.

EGaIn-Assisted Room-Temperature Sintering of Silver Nanoparticles for Stretchable, Inkjet-Printed, Thin-Film Electronics.

PubMed

Tavakoli, Mahmoud; Malakooti, Mohammad H; Paisana, Hugo; Ohm, Yunsik; Marques, Daniel Green; Alhais Lopes, Pedro; Piedade, Ana P; de Almeida, Anibal T; Majidi, Carmel

2018-05-29

Coating inkjet-printed traces of silver nanoparticle (AgNP) ink with a thin layer of eutectic gallium indium (EGaIn) increases the electrical conductivity by six-orders of magnitude and significantly improves tolerance to tensile strain. This enhancement is achieved through a room-temperature "sintering" process in which the liquid-phase EGaIn alloy binds the AgNP particles (≈100 nm diameter) to form a continuous conductive trace. Ultrathin and hydrographically transferrable electronics are produced by printing traces with a composition of AgNP-Ga-In on a 5 µm-thick temporary tattoo paper. The printed circuit is flexible enough to remain functional when deformed and can support strains above 80% with modest electromechanical coupling (gauge factor ≈1). These mechanically robust thin-film circuits are well suited for transfer to highly curved and nondevelopable 3D surfaces as well as skin and other soft deformable substrates. In contrast to other stretchable tattoo-like electronics, the low-cost processing steps introduced here eliminate the need for cleanroom fabrication and instead requires only a commercial desktop printer. Most significantly, it enables functionalities like "electronic tattoos" and 3D hydrographic transfer that have not been previously reported with EGaIn or EGaIn-based biphasic electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Organic–Inorganic Eu3+/Tb3+ codoped hybrid films for temperature mapping in integrated circuits

PubMed Central

Brites, Carlos D. S.; Lima, Patrícia P.; Silva, Nuno J. O.; Millán, Angel; Amaral, Vitor S.; Palacio, Fernando; Carlos, Luís D.

2013-01-01

The continuous decrease on the geometric size of electronic devices and integrated circuits generates higher local power densities and localized heating problems that cannot be characterized by conventional thermographic techniques. Here, a self-referencing intensity-based molecular thermometer involving a di-ureasil organic-inorganic hybrid thin film co-doped with Eu3+ and Tb3+ tris (β-diketonate) chelates is used to obtain the temperature map of a FR4 printed wiring board with spatio-temporal resolutions of 0.42 μm/4.8 ms. PMID:24790938

Integrated circuit package with lead structure and method of preparing the same

NASA Technical Reports Server (NTRS)

Kennedy, B. W. (Inventor)

1973-01-01

A beam-lead integrated circuit package assembly including a beam-lead integrated circuit chip, a lead frame array bonded to projecting fingers of the chip, a rubber potting compound disposed around the chip, and an encapsulating molded plastic is described. The lead frame array is prepared by photographically printing a lead pattern on a base metal sheet, selectively etching to remove metal between leads, and plating with gold. Joining of the chip to the lead frame array is carried out by thermocompression bonding of mating goldplated surfaces. A small amount of silicone rubber is then applied to cover the chip and bonded joints, and the package is encapsulated with epoxy resin, applied by molding.

Flow-enhanced solution printing of all-polymer solar cells

DOE PAGES

Diao, Ying; Zhou, Yan; Kurosawa, Tadanori; ...

2015-08-12

Morphology control of solution coated solar cell materials presents a key challenge limiting their device performance and commercial viability. Here we present a new concept for controlling phase separation during solution printing using an all-polymer bulk heterojunction solar cell as a model system. The key aspect of our method lies in the design of fluid flow using a microstructured printing blade, on the basis of the hypothesis of flow-induced polymer crystallization. Our flow design resulted in a similar to 90% increase in the donor thin film crystallinity and reduced microphase separated donor and acceptor domain sizes. The improved morphology enhancedmore » all metrics of solar cell device performance across various printing conditions, specifically leading to higher short-circuit current, fill factor, open circuit voltage and significantly reduced device-to-device variation. However, we expect our design concept to have broad applications beyond all-polymer solar cells because of its simplicity and versatility.« less

Flow-enhanced solution printing of all-polymer solar cells

PubMed Central

Diao, Ying; Zhou, Yan; Kurosawa, Tadanori; Shaw, Leo; Wang, Cheng; Park, Steve; Guo, Yikun; Reinspach, Julia A.; Gu, Kevin; Gu, Xiaodan; Tee, Benjamin C. K.; Pang, Changhyun; Yan, Hongping; Zhao, Dahui; Toney, Michael F.; Mannsfeld, Stefan C. B.; Bao, Zhenan

2015-01-01

Morphology control of solution coated solar cell materials presents a key challenge limiting their device performance and commercial viability. Here we present a new concept for controlling phase separation during solution printing using an all-polymer bulk heterojunction solar cell as a model system. The key aspect of our method lies in the design of fluid flow using a microstructured printing blade, on the basis of the hypothesis of flow-induced polymer crystallization. Our flow design resulted in a ∼90% increase in the donor thin film crystallinity and reduced microphase separated donor and acceptor domain sizes. The improved morphology enhanced all metrics of solar cell device performance across various printing conditions, specifically leading to higher short-circuit current, fill factor, open circuit voltage and significantly reduced device-to-device variation. We expect our design concept to have broad applications beyond all-polymer solar cells because of its simplicity and versatility. PMID:26264528

The separation of waste printed circuit board by dissolving bromine epoxy resin using organic solvent.

PubMed

Zhu, P; Chen, Y; Wang, L Y; Zhou, M; Zhou, J

2013-02-01

Separation of waste printed circuit boards (WPCBs) has been a bottleneck in WPCBs resource processing. In this study, the separation of WPCBs was performed using dimethyl sulfoxide (DMSO) as a solvent. Various parameters, which included solid to liquid ratio, temperature, WPCB sizes, and time, were studied to understand the separation of WPCBs by dissolving bromine epoxy resin using DMSO. Experimental results showed that the concentration of dissolving the bromine epoxy resin increased with increasing various parameters. The optimum condition of complete separation of WPCBs was solid to liquid ratio of 1:7 and WPCB sizes of 16 mm(2) at 145°C for 60 min. The used DMSO was vapored under the decompression, which obtained the regenerated DMSO and dissolved bromine epoxy resin. This clean and non-polluting technology offers a new way to separate valuable materials from WPCBs and prevent the environmental pollution of waste printed circuit boards effectively. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Methods for fabrication of flexible hybrid electronics

NASA Astrophysics Data System (ADS)

Street, Robert A.; Mei, Ping; Krusor, Brent; Ready, Steve E.; Zhang, Yong; Schwartz, David E.; Pierre, Adrien; Doris, Sean E.; Russo, Beverly; Kor, Siv; Veres, Janos

2017-08-01

Printed and flexible hybrid electronics is an emerging technology with potential applications in smart labels, wearable electronics, soft robotics, and prosthetics. Printed solution-based materials are compatible with plastic film substrates that are flexible, soft, and stretchable, thus enabling conformal integration with non-planar objects. In addition, manufacturing by printing is scalable to large areas and is amenable to low-cost sheet-fed and roll-to-roll processes. FHE includes display and sensory components to interface with users and environments. On the system level, devices also require electronic circuits for power, memory, signal conditioning, and communications. Those electronic components can be integrated onto a flexible substrate by either assembly or printing. PARC has developed systems and processes for realizing both approaches. This talk presents fabrication methods with an emphasis on techniques recently developed for the assembly of off-the-shelf chips. A few examples of systems fabricated with this approach are also described.

Laser-induced forward transfer for printed electronics applications

NASA Astrophysics Data System (ADS)

Fernández-Pradas, J. M.; Sopeña, P.; González-Torres, S.; Arrese, J.; Cirera, A.; Serra, P.

2018-02-01

Laser-induced forward transfer (LIFT) is a printing technique based on the action of a laser pulse that is focused on a thin film of a precursor ink for getting the transfer of a droplet onto a receiver substrate. The experiments presented in this article aim to demonstrate the ability of LIFT to produce electronic circuits on paper, a substrate that is flexible, cheap and recyclable. Tests were conducted to study the printing of conductive tracks with an Ag ink. The printing of a suspension of carbon nanofibers was also studied to demonstrate the ability of LIFT for printing inks with particles with some microns in size that provoke inkjet nozzles to clog. As a proof-of-concept of the LIFT possibilities, both inks were used to print entirely by LIFT a functional humidity sensor on a piece of paper. All the LIFT experiments were performed with a Nd:YAG laser that delivers pulses of a few hundreds of ns in an attempt to approach the technique to laser systems that are already introduced in many production lines for marking and labeling.

All-printed magnetically self-healing electrochemical devices

PubMed Central

Bandodkar, Amay J.; López, Cristian S.; Vinu Mohan, Allibai Mohanan; Yin, Lu; Kumar, Rajan; Wang, Joseph

2016-01-01

The present work demonstrates the synthesis and application of permanent magnetic Nd2Fe14B microparticle (NMP)–loaded graphitic inks for realizing rapidly self-healing inexpensive printed electrochemical devices. The incorporation of NMPs into the printable ink imparts impressive self-healing ability to the printed conducting trace, with rapid (~50 ms) recovery of repeated large (3 mm) damages at the same or different locations without any user intervention or external trigger. The permanent and surrounding-insensitive magnetic properties of the NMPs thus result in long-lasting ability to repair extreme levels of damage, independent of ambient conditions. This remarkable self-healing capability has not been reported for existing man-made self-healing systems and offers distinct advantages over common capsule and intrinsically self-healing systems. The printed system has been characterized by leveraging crystallographic, magnetic hysteresis, microscopic imaging, electrical conductivity, and electrochemical techniques. The real-life applicability of the new self-healing concept is demonstrated for the autonomous repair of all-printed batteries, electrochemical sensors, and wearable textile-based electrical circuits, indicating considerable promise for widespread practical applications and long-lasting printed electronic devices. PMID:27847875

Flexible ambipolar organic field-effect transistors with reverse-offset-printed silver electrodes for a complementary inverter.

PubMed

Park, Junsu; Kim, Minseok; Yeom, Seung-Won; Ha, Hyeon Jun; Song, Hyenggun; Min Jhon, Young; Kim, Yun-Hi; Ju, Byeong-Kwon

2016-06-03

We report ambipolar organic field-effect transistors and complementary inverter circuits with reverse-offset-printed (ROP) Ag electrodes fabricated on a flexible substrate. A diketopyrrolopyrrole-based co-polymer (PDPP-TAT) was used as the semiconductor and poly(methyl methacrylate) was used as the gate insulator. Considerable improvement is observed in the n-channel electrical characteristics by inserting a cesium carbonate (Cs2CO3) as the electron-injection/hole-blocking layer at the interface between the semiconductors and the electrodes. The saturation mobility values are 0.35 cm(2) V(-1) s(-1) for the p-channel and 0.027 cm(2) V(-1) s(-1) for the n-channel. A complementary inverter is demonstrated based on the ROP process, and it is selectively controlled by the insertion of Cs2CO3 onto the n-channel region via thermal evaporation. Moreover, the devices show stable operation during the mechanical bending test using tensile strains ranging from 0.05% to 0.5%. The results confirm that these devices have great potential for use in flexible and inexpensive integrated circuits over a large area.

Study of Photosensitive Dry Films Absorption for Printed Circuit Boards by Photoacoustic Technique

NASA Astrophysics Data System (ADS)

Hernández, R.; Zaragoza, J. A. Barrientos; Jiménez-Pérez, J. L.; Orea, A. Cruz; Correa-Pacheco, Z. N.

2017-08-01

In this work, the study of photosensitive dry-type films by photoacoustic technique is proposed. The dry film photoresist is resistant to chemical etching for printed circuit boards such as ferric chloride, sodium persulfate or ammonium, hydrochloric acid. It is capable of faithfully reproducing circuit pattern exposed to ultraviolet light (UV) through a negative. Once recorded, the uncured portion is removed with alkaline solution. It is possible to obtain good results in surface mount circuits with tracks of 5 mm. Furthermore, the solid resin films are formed by three layers, two protective layers and a UV-sensitive optical absorption layer in the range of 325 nm to 405 nm. By means of optical absorption of UV-visible rays emitted by a low-power Xe lamp, the films transform this energy into thermal waves generated by the absorption of optical radiation and subsequently no-radiative de-excitation occurs. The photoacoustic spectroscopy is a useful technique to measure the transmittance and absorption directly. In this study, the optical absorption spectra of the three layers of photosensitive dry-type films were obtained as a function of the wavelength, in order to have a knowledge of the absorber layer and the protective layers. These analyses will give us the physical properties of the photosensitive film, which are very important in curing the dry film for applications in printed circuit boards.

Development of high-performance printed organic field-effect transistors and integrated circuits.

PubMed

Xu, Yong; Liu, Chuan; Khim, Dongyoon; Noh, Yong-Young

2015-10-28

Organic electronics is regarded as an important branch of future microelectronics especially suited for large-area, flexible, transparent, and green devices, with their low cost being a key benefit. Organic field-effect transistors (OFETs), the primary building blocks of numerous expected applications, have been intensively studied, and considerable progress has recently been made. However, there are still a number of challenges to the realization of high-performance OFETs and integrated circuits (ICs) using printing technologies. Therefore, in this perspective article, we investigate the main issues concerning developing high-performance printed OFETs and ICs and seek strategies for further improvement. Unlike many other studies in the literature that deal with organic semiconductors (OSCs), printing technology, and device physics, our study commences with a detailed examination of OFET performance parameters (e.g., carrier mobility, threshold voltage, and contact resistance) by which the related challenges and potential solutions to performance development are inspected. While keeping this complete understanding of device performance in mind, we check the printed OFETs' components one by one and explore the possibility of performance improvement regarding device physics, material engineering, processing procedure, and printing technology. Finally, we analyze the performance of various organic ICs and discuss ways to optimize OFET characteristics and thus develop high-performance printed ICs for broad practical applications.

Silver Ink For Jet Printing

NASA Technical Reports Server (NTRS)

Vest, R. W.; Singaram, Saraswathi

1989-01-01

Metallo-organic ink containing silver (with some bismuth as adhesion agent) applied to printed-circuit boards and pyrolized in air to form electrically conductive patterns. Ink contains no particles of silver, does not have to be mixed during use to maintain homogeneity, and applied to boards by ink-jet printing heads. Consists of silver neodecanoate and bismuth 2-ethylhexanoate dissolved in xylene and/or toluene.

Detection of Banned and Restricted Ozone-Depleting Chemicals in Printed Circuit Boards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Richard N.; Wright, Bob W.

2008-12-01

A study directed toward the detection of halogenated solvents in the matrix of circuit boards has recently been completed. This work was undertaken to demonstrate the potential for reliable detection of solvents used during the fabrication of printed circuit boards (PCB). Since many of these solvents are now, or soon will be, restricted under the terms of legislation enacted in response to the Montreal Protocol and other international agreements, the work described here, conducted over a period of more that 4 years, has provided guidance for the development of chromatographic system and analytical protocol to assure compliance with regulations introducedmore » to control, or ban, industrial solvents associated with adverse environmental impact.« less

Printed circuit dispersive transmission line

DOEpatents

Ikezi, Hiroyuki; Lin-Liu, Yuh-Ren; DeGrassie, John S.

1991-01-01

A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other.

The Use of 3D Printing in the Development of Gaseous Radiation Detectors

NASA Astrophysics Data System (ADS)

Fargher, Sam; Steer, Chris; Thompson, Lee

2018-01-01

Fused Deposition Modelling has been used to produce a small, single wire, Iarocci-style drift tube to demonstrate the feasibility of using the Additive Manufacturing technique to produce cheap detectors, quickly. Recent technological developments have extended the scope of Additive Manufacturing, or 3D printing, to the possibility of fabricating Gaseous Radiation Detectors, such as Single Wire Proportional Counters and Time Projection Chambers. 3D printing could allow for the production of customisable, modular detectors; that can be easily created and replaced and the possibility of printing detectors on-site in remote locations and even for outreach within schools. The 3D printed drift tube was printed using Polylactic acid to produce a gas volume in the shape of an inverted triangular prism; base length of 28 mm, height 24.25 mm and tube length 145 mm. A stainless steel anode wire was placed in the centre of the tube, mid-print. P5 gas (95% Argon, 5% Methane) was used as the drift gas and a circuit was built to capacitively decouple signals from the high voltage. The signal rate and average pulse height of cosmic ray muons were measured over a range of bias voltages to characterise and prove correct operation of the printed detector.

General technique for the integration of MIC/MMIC'S with waveguides

NASA Technical Reports Server (NTRS)

Geller, Bernard D. (Inventor); Zaghloul, Amir I. (Inventor)

1987-01-01

A technique for packaging and integrating of a microwave integrated circuit (MIC) or monolithic microwave integrated circuit (MMIC) with a waveguide uses a printed conductive circuit pattern on a dielectric substrate to transform impedance and mode of propagation between the MIC/MMIC and the waveguide. The virtually coplanar circuit pattern lies on an equipotential surface within the waveguide and therefore makes possible single or dual polarized mode structures.

Simulation of high SNR photodetector with L-C coupling and transimpedance amplifier circuit and its verification

NASA Astrophysics Data System (ADS)

Wang, Shaofeng; Xiang, Xiao; Zhou, Conghua; Zhai, Yiwei; Quan, Runai; Wang, Mengmeng; Hou, Feiyan; Zhang, Shougang; Dong, Ruifang; Liu, Tao

2017-01-01

In this paper, a model for simulating the optical response and noise performances of photodetectors with L-C coupling and transimpedance amplification circuit is presented. To verify the simulation, two kinds of photodetectors, which are based on the same printed-circuit-board (PCB) designing and PIN photodiode but different operational amplifiers, are developed and experimentally investigated. Through the comparisons between the numerical simulation results and the experimentally obtained data, excellent agreements are achieved, which show that the model provides a highly efficient guide for the development of a high signal to noise ratio photodetector. Furthermore, the parasite capacitances on the developed PCB, which are always hardly measured but play a non-negligible influence on the photodetectors' performances, are estimated.

Simulation of high SNR photodetector with L-C coupling and transimpedance amplifier circuit and its verification.

PubMed

Wang, Shaofeng; Xiang, Xiao; Zhou, Conghua; Zhai, Yiwei; Quan, Runai; Wang, Mengmeng; Hou, Feiyan; Zhang, Shougang; Dong, Ruifang; Liu, Tao

2017-01-01

In this paper, a model for simulating the optical response and noise performances of photodetectors with L-C coupling and transimpedance amplification circuit is presented. To verify the simulation, two kinds of photodetectors, which are based on the same printed-circuit-board (PCB) designing and PIN photodiode but different operational amplifiers, are developed and experimentally investigated. Through the comparisons between the numerical simulation results and the experimentally obtained data, excellent agreements are achieved, which show that the model provides a highly efficient guide for the development of a high signal to noise ratio photodetector. Furthermore, the parasite capacitances on the developed PCB, which are always hardly measured but play a non-negligible influence on the photodetectors' performances, are estimated.

3D printed electromagnetic transmission and electronic structures fabricated on a single platform using advanced process integration techniques

NASA Astrophysics Data System (ADS)

Deffenbaugh, Paul Issac

3D printing has garnered immense attention from many fields including in-office rapid prototyping of mechanical parts, outer-space satellite replication, garage functional firearm manufacture, and NASA rocket engine component fabrication. 3D printing allows increased design flexibility in the fabrication of electronics, microwave circuits and wireless antennas and has reached a level of maturity which allows functional parts to be printed. Much more work is necessary in order to perfect the processes of 3D printed electronics especially in the area of automation. Chapter 1 shows several finished prototypes of 3D printed electronics as well as newly developed techniques in fabrication. Little is known about the RF and microwave properties and applications of the standard materials which have been developed for 3D printing. Measurement of a wide variety of materials over a broad spectrum of frequencies up to 10 GHz using a variety of well-established measurement methods is performed throughout chapter 2. Several types of high frequency RF transmission lines are fabricated and valuable model-matched data is gathered and provided in chapter 3 for future designers' use. Of particular note is a fully 3D printed stripline which was automatically fabricated in one process on one machine. Some core advantages of 3D printing RF/microwave components include rapid manufacturing of complex, dimensionally sensitive circuits (such as antennas and filters which are often iteratively tuned) and the ability to create new devices that cannot be made using standard fabrication techniques. Chapter 4 describes an exemplary fully 3D printed curved inverted-F antenna.

Unit: Electric Circuits, Inspection Pack, National Trial Print.

ERIC Educational Resources Information Center

Australian Science Education Project, Toorak, Victoria.

As a part of the unit materials in the series produced by the Australian Science Education Project, this teacher edition is primarily composed of a core relating to simple circuits, a test form, and options. Options are given under the headings: Your Invention; "How Long Does a Call Last?"; One, Two, Three Wires; Parallel Circuits; More…

Applications Of Graphite Fluoride Fibers In Outer Space

NASA Technical Reports Server (NTRS)

Hung, Ching-Cheng; Long, Martin; Dever, Therese

1993-01-01

Report characterizes graphite fluoride fibers made from commercially available graphitized carbon fibers and discusses some potential applications of graphite fluoride fibers in outer space. Applications include heat-sinking printed-circuit boards, solar concentrators, and absorption of radar waves. Other applications based on exploitation of increased resistance to degradation by atomic oxygen, present in low orbits around Earth.

Fabrication of Bendable Circuits on a Polydimethylsiloxane (PDMS) Surface by Inkjet Printing Semi-Wrapped Structures

PubMed Central

Sun, Jiazhen; Jiang, Jieke; Bao, Bin; Wang, Si; He, Min; Zhang, Xingye; Song, Yanlin

2016-01-01

In this work, an effective method was developed to fabricate bendable circuits on a polydimethylsiloxane (PDMS) surface by inkjet printing semi-wrapped structures. It is demonstrated that the precured PDMS liquid film could influence the depositing morphology of coalesced silver precursor inkjet droplets. Accordingly, continuous and uniform lines with a semi-wrapped structure were fabricated on the PDMS surface. When the printed silver precursor was reduced to Ag nanoparticles, the fabricated conductive film exhibited good transparency and high bendability. This work presented a facile way to fabricate flexible patterns on a PDMS surface without any complicated modification or special equipment. Meanwhile, an in situ hydrazine reduction of Ag has been reported using the vapor phase method in the fabricating process. PMID:28773374

Surface Flashover on Epoxy-Resin Printed Circuit Boards in Vacuum under Electron Irradiation

NASA Astrophysics Data System (ADS)

Fujii, Haruhisa; Hasegawa, Taketoshi; Osuga, Hiroyuki; Matsui, Katsuaki

This paper deals with the surface flashover characteristics of dielectric material in vacuum during electron beam irradiation in order to design adequately the conductive patterns on printed circuit boards used inside a spacecraft. The dielectric material, glass-fiber reinforced epoxy resin, and the electrodes printed on it were irradiated with electrons of the energy of 3-10 keV. DC high voltage was applied between the two electrodes during electron irradiation. The voltage was increased stepwise until the surface flashover occurred on the dielectric material. We obtained the results that the surface flashover voltage increased with the insulation distance between the electrodes but electron irradiation made the flashover voltage lower. The flashover voltage characteristics were obtained as parameters of the electrode distance and the energy of the electron beam.

Artificial Muscle (AM) Cilia Array for Underwater Systems

DTIC Science & Technology

2016-12-15

structures, including cilia-like structures. Specifically, a custom 3D printer was created that utilizes custom-made Nafion filament for 30 printing of custom... printing ) of IPMC material to create custom-shaped AM structures, including cilia-like structures. Various custom-shaped AM structures were fabricated via...integrating square cross-section IPMC actuators with a printed circuit board power delivery system. IV. Concise Accomplishments Performance

New technology for separating resin powder and fiberglass powder from fiberglass-resin powder of waste printed circuit boards.

PubMed

Li, Jia; Gao, Bei; Xu, Zhenming

2014-05-06

New recycling technologies have been developed lately to enhance the value of the fiberglass powder-resin powder fraction (FRP) from waste printed circuit boards. The definite aim of the present paper is to present some novel methods that use the image forces for the separation of the resin powder and fiberglass powder generated from FRP during the corona electrostatic separating process. The particle shape charactization and particle trajectory simulation were performed on samples of mixed non-metallic particles. The simulation results pointed out that particles of resin powder and particles of fiberglass powder had different detach trajectories at the conditions of the same size and certain device parameters. An experiment carried out using a corona electrostatic separator validated the possibility of sorting these particles based on the differences in their shape characteristics. The differences in the physical properties of the different types of particles provided the technical basis for the development of electrostatic separation technologies for the recycling industry.

A long-term static immersion experiment on the leaching behavior of heavy metals from waste printed circuit boards.

PubMed

Zhao, Guo-Hua; Luo, Xing-Zhang; Chen, Gui; Zhao, Yong-Jun

2014-08-01

Printed circuit boards (PCBs) are the main components of electrical and electronic equipment (EEE). Waste PCBs contain several kinds of heavy metals, including Cu, Pb and Zn. We characterize the leaching of heavy metals (Cu, Pb, Zn and Ni) from waste PCBs in a pH range of 3.0 to 5.6 using a novel approach based on batch pH-static leaching experiments in this work. The results indicate that the leaching behavior of Cu, Pb, Zn and Ni is strongly dependent on pH. Leaching behavior also varies with different pH values and leaching times. The maximum concentrations of Cu, Pb, Zn and Ni in leachate from waste PCBs were 335.00, 17.57, 2.40 and 2.33 mg L(-1), respectively. The highest Pb, Ni, and Cu concentrations leached significantly exceeded the European Union waste-acceptance limit values with respect to inert waste landfills. The leaching of metals follows the shrinking core model with surface reaction control.

Extremely Robust and Patternable Electrodes for Copy-Paper-Based Electronics.

PubMed

Ahn, Jaeho; Seo, Ji-Won; Lee, Tae-Ik; Kwon, Donguk; Park, Inkyu; Kim, Taek-Soo; Lee, Jung-Yong

2016-07-27

We propose a fabrication process for extremely robust and easily patternable silver nanowire (AgNW) electrodes on paper. Using an auxiliary donor layer and a simple laminating process, AgNWs can be easily transferred to copy paper as well as various other substrates using a dry process. Intercalating a polymeric binder between the AgNWs and the substrate through a simple printing technique enhances adhesion, not only guaranteeing high foldability of the electrodes, but also facilitating selective patterning of the AgNWs. Using the proposed process, extremely crease-tolerant electronics based on copy paper can be fabricated, such as a printed circuit board for a 7-segment display, portable heater, and capacitive touch sensor, demonstrating the applicability of the AgNWs-based electrodes to paper electronics.

Inkjet printed large-area flexible circuits: a simple methodology for optimizing the printing quality

NASA Astrophysics Data System (ADS)

Cheng, Tao; Wu, Youwei; Shen, Xiaoqin; Lai, Wenyong; Huang, Wei

2018-01-01

In this work, a simple methodology was developed to enhance the patterning resolution of inkjet printing, involving process optimization as well as substrate modification and treatment. The line width of the inkjet-printed silver lines was successfully reduced to 1/3 of the original value using this methodology. Large-area flexible circuits with delicate patterns and good morphology were thus fabricated. The resultant flexible circuits showed excellent electrical conductivity as low as 4.5 Ω/□ and strong tolerance to mechanical bending. The simple methodology is also applicable to substrates with various wettability, which suggests a general strategy to enhance the printing quality of inkjet printing for manufacturing high-performance large-area flexible electronics. Project supported by the National Key Basic Research Program of China (Nos. 2014CB648300, 2017YFB0404501), the National Natural Science Foundation of China (Nos. 21422402, 21674050), the Natural Science Foundation of Jiangsu Province (Nos. BK20140060, BK20130037, BK20140865, BM2012010), the Program for Jiangsu Specially-Appointed Professors (No. RK030STP15001), the Program for New Century Excellent Talents in University (No. NCET-13-0872), the NUPT "1311 Project" and Scientific Foundation (Nos. NY213119, NY213169), the Synergetic Innovation Center for Organic Electronics and Information Displays, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), the Leading Talent of Technological Innovation of National Ten-Thousands Talents Program of China, the Excellent Scientific and Technological Innovative Teams of Jiangsu Higher Education Institutions (No. TJ217038), the Program for Graduate Students Research and Innovation of Jiangsu Province (No. KYZZ16-0253), and the 333 Project of Jiangsu Province (Nos. BRA2017402, BRA2015374).

Method of printed circuits and semiconductor substrates material parameters extraction using wideband reflection measurements

NASA Astrophysics Data System (ADS)

Savin, A. A.; Guba, V. G.; Ladur, A. A.; Bykova, O. N.

2018-05-01

This paper is dedicated to a new method of high frequency circuits material properties extraction based on the reflection measurements of a line shorted two or more times along its length. The line should be fabricated on the material under test. To achieve more precise calculation results, the proposed method uses processing in the time domain. The experimental results section shows obtained assessments for relative permittivity and dielectric loss tangent of the RO4350B hydrocarbon ceramic laminate. Measurements have been conducted over the frequency range up to 20 GHz.

A Simple Picaxe Microcontroller Pulse Source for Juxtacellular Neuronal Labelling.

PubMed

Verberne, Anthony J M

2016-10-19

Juxtacellular neuronal labelling is a method which allows neurophysiologists to fill physiologically-identified neurons with small positively-charged marker molecules. Labelled neurons are identified by histochemical processing of brain sections along with immunohistochemical identification of neuropeptides, neurotransmitters, neurotransmitter transporters or biosynthetic enzymes. A microcontroller-based pulser circuit and associated BASIC software script is described for incorporation into the design of a commercially-available intracellular electrometer for use in juxtacellular neuronal labelling. Printed circuit board construction has been used for reliability and reproducibility. The current design obviates the need for a separate digital pulse source and simplifies the juxtacellular neuronal labelling procedure.

High Temperature Pt/Alumina Co-Fired System for 500 C Electronic Packaging Applications

NASA Technical Reports Server (NTRS)

Chen, Liang-Yu; Neudeck, Philip G.; Spry, David J.; Beheim, Glenn M.; Hunter, Gary W.

2015-01-01

Gold thick-film metallization and 96 alumina substrate based prototype packaging system developed for 500C SiC electronics and sensors is briefly reviewed, the needs of improvement are discussed. A high temperature co-fired alumina material system based packaging system composed of 32-pin chip-level package and printed circuit board is discussed for packaging 500C SiC electronics and sensors.

PVC-based composite material containing recycled non-metallic printed circuit board (PCB) powders.

PubMed

Wang, Xinjie; Guo, Yuwen; Liu, Jingyang; Qiao, Qi; Liang, Jijun

2010-12-01

The study is directed to the use of non-metallic powders obtained from comminuted recycled paper-based printed circuit boards (PCBs) as an additive to polyvinyl chloride (PVC) substrate. The physical properties of the non-metallic PCB (NMPCB) powders were measured, and the morphological, mechanical and thermal properties of the NMPCB/PVC composite material were investigated. The results show that recycled NMPCB powders, when added below a threshold, tended to increase the tensile strength and bending strength of PVC. When 20 wt% NMPCB powders (relative to the substrate PVC) of an average diameter of 0.08 mm were added, the composite tensile strength and bending strength reached 22.6 MPa and 39.83 MPa, respectively, representing 107.2% and 123.1% improvement over pure PVC. The elongation at break of the composite material reached 151.94% of that of pure PVC, while the Vicat softening temperature of the composite material did not increase significantly compared to the pure PVC. The above results suggest that paper-based NMPCB powders, when used at appropriate amounts, can be effective for toughening PVC. Thus, this study suggests a new route for reusing paper-based NMPCB, which may have a significant beneficial environmental impact. Copyright © 2010 Elsevier Ltd. All rights reserved.

Low-Cost Fabrication of Printed Electronics Devices through Continuous Wave Laser-Induced Forward Transfer.

PubMed

Sopeña, Pol; Arrese, Javier; González-Torres, Sergio; Fernández-Pradas, Juan Marcos; Cirera, Albert; Serra, Pere

2017-09-06

Laser-induced forward transfer (LIFT) is a direct-writing technique that allows printing inks from a liquid film in a similar way to inkjet printing but with fewer limitations concerning ink viscosity and loading particle size. In this work, we prove that liquid inks can be printed through LIFT by using continuous wave (CW) instead of pulsed lasers, which allows a substantial reduction in the cost of the printing system. Through the fabrication of a functional circuit on both rigid and flexible substrates (plastic and paper), we provide a proof-of-concept that demonstrates the versatility of the technique for printed electronics applications.

Composition and Elution Behavior of Various Elements from Printed Circuit Boards, Cathode-ray Tube Glass, and Liquid-crystal Displays in Waste Consumer Electronics.

PubMed

Inaba, Kazuho; Murata, Tomoyoshi; Yamamura, Shigeki; Nagano, Masaaki; Iwasaki, Kazuhiro; Nakajima, Daisuke; Takigami, Hidetaka

2018-01-01

The contents and elution behavior of metals in consumer electronics parts were determined so as to understand their maximum environmental risk. Elements contained most in printed-circuit boards were Cu, Si, Br, Ca, Al, Sn, Pb, Sb, Ba, Fe, Ni, Ti, and Zn; in cathode-ray tube glass were Si, Pb, Ba, Sr, Zn, Zr, Ca, and Sb; in arsenic contained liquid-crystal displays were Si, Ca, Sr, Ba, As, and Fe; and in antimony contained liquid-crystal displays were Si, Ba, Ca, Sb, Sr, Fe, and Sn. The elements eluted most from printed-circuit boards were Zn, Pb, and Cu; from cathode-ray tube glass were Pb, Zn, B, Ba, and Si; and from liquid-crystal displays were B and Si, and the toxic As and Sb. The amount eluted was greatest at acidic pH. It was revealed that officially recommended 6-h-shaking with a pure water test was insufficient to understand the real environmental risk of waste electronics.

Examining the technology acceptance for dismantling of waste printed circuit boards in light of recycling and environmental concerns.

PubMed

Duan, Huabo; Hou, Kun; Li, Jinhui; Zhu, Xiaodong

2011-03-01

The dismantling of printed circuit board assemblies (PCBAs) and the recovery of their useful materials can lead to serious environmental impacts mainly due to their complicated physical structure and the variety of toxic elements contained in their material composition. So far, less attention has been paid to their responsible recycling compared to that of bare printed circuit boards. Combined with other materials recovery process, proper dismantling of PCBAs is beneficial to conserve scarce resources, reuse the components, and eliminate or safely dispose of hazardous materials. In analyzing the generation, resources potential and hazardous risk of scrap PCBAs, technologies used for the dismantling of waste PCBAs have been widely investigated and reviewed from the aspects of both industrial application and laboratory-scale studies. In addition, the feasibility of PCBA dismantling has been discussed, the determinants of which, including the heating conditions and mechanical properties have been identified. Moreover, this paper evaluates the environmental consequences caused by the dismantling of PCBAs. Copyright © 2010 Elsevier Ltd. All rights reserved.

Immobilization of Acidithiobacillus ferrooxidans on Cotton Gauze for the Bioleaching of Waste Printed Circuit Boards.

PubMed

Nie, Hongyan; Zhu, Nengwu; Cao, Yanlan; Xu, Zhiguo; Wu, Pingxiao

2015-10-01

The bioleaching parameters of metal concentrates from waste printed circuit boards by Acidithiobacillus ferrooxidans immobilized on cotton gauze in a two-step reactor were investigated in this study. The results indicated that an average ferrous iron oxidation rate of 0.54 g/(L·h) and a ferrous iron oxidation ratio of 96.90 % were obtained after 12 h at aeration rate of 1 L/min in bio-oxidation reactor. After 96 h, the highest leaching efficiency of copper reached 91.68 % under the conditions of the content of the metal powder 12 g/L, the retention time 6 h, and the aeration rate 1 L/min. The bioleaching efficiency of copper could be above 91.12 % under repeated continuous batch operation. Meanwhile, 95.32 % of zinc, 90.32 % of magnesium, 86.31 % of aluminum, and 59.07 % of nickel were extracted after 96 h. All the findings suggested that the recovery of metal concentrates from waste printed circuit boards via immobilization of A. ferrooxidans on cotton gauze was feasible.

Internet of "printed" Things: low-cost fabrication of autonomous sensing nodes by inkjet printing

NASA Astrophysics Data System (ADS)

Kawahara, Yoshihiro

2014-11-01

"What if electronics devices are printed using an inkjet printer even at home?" "What if those devices no longer need a battery?" I will introduce two enabling technologies for the Internet of Things concept. 1. Instant Inkjet Circuits: A low cost, fast and accessible technology to support the rapid prototyping of electronic devices. We demonstrated that "sintering-free" silver nano particle ink with a commodity inkjet printer can be used to fabricate printed circuit board and high-frequency applications such as antennas and sensors. The technology is now commercialized by AgIC, Inc. 2. Wireless Power: Although large amounts of data can be exchanged over a wireless communication link, mobile devices are still tethered by power cables. We are trying to solve this problem by two different approaches: energy harvesting. A simple circuitry comprised of diodes and capacitor can convert ambient radio signals into DC current. Our research revealed the signals from TV tower located 6.5km apart could be used to feed 100 microwatts to power microcontrollers.

Analysis of complex environment effect on near-field emission

NASA Astrophysics Data System (ADS)

Ravelo, B.; Lalléchère, S.; Bonnet, P.; Paladian, F.

2014-10-01

The article is dealing with uncertainty analyses of radiofrequency circuits electromagnetic compatibility emission based on the near-field/near-field (NF/NF) transform combined with stochastic approach. By using 2D data corresponding to electromagnetic (EM) field (X=E or H) scanned in the observation plane placed at the position z0 above the circuit under test (CUT), the X field map was extracted. Then, uncertainty analyses were assessed via the statistical moments from X component. In addition, stochastic collocation based was considered and calculations were applied to planar EM NF radiated by the CUTs as Wilkinson power divider and a microstrip line operating at GHz levels. After Matlab implementation, the mean and standard deviation were assessed. The present study illustrates how the variations of environmental parameters may impact EM fields. The NF uncertainty methodology can be applied to any physical parameter effects in complex environment and useful for printed circuit board (PCBs) design guideline.

Fully printable, strain-engineered electronic wrap for customizable soft electronics.

PubMed

Byun, Junghwan; Lee, Byeongmoon; Oh, Eunho; Kim, Hyunjong; Kim, Sangwoo; Lee, Seunghwan; Hong, Yongtaek

2017-03-24

Rapid growth of stretchable electronics stimulates broad uses in multidisciplinary fields as well as industrial applications. However, existing technologies are unsuitable for implementing versatile applications involving adaptable system design and functions in a cost/time-effective way because of vacuum-conditioned, lithographically-predefined processes. Here, we present a methodology for a fully printable, strain-engineered electronic wrap as a universal strategy which makes it more feasible to implement various stretchable electronic systems with customizable layouts and functions. The key aspects involve inkjet-printed rigid island (PRI)-based stretchable platform technology and corresponding printing-based automated electronic functionalization methodology, the combination of which provides fully printed, customized layouts of stretchable electronic systems with simplified process. Specifically, well-controlled contact line pinning effect of printed polymer solution enables the formation of PRIs with tunable thickness; and surface strain analysis on those PRIs leads to the optimized stability and device-to-island fill factor of strain-engineered electronic wraps. Moreover, core techniques of image-based automated pinpointing, surface-mountable device based electronic functionalizing, and one-step interconnection networking of PRIs enable customized circuit design and adaptable functionalities. To exhibit the universality of our approach, multiple types of practical applications ranging from self-computable digital logics to display and sensor system are demonstrated on skin in a customized form.

Fully printable, strain-engineered electronic wrap for customizable soft electronics

NASA Astrophysics Data System (ADS)

Byun, Junghwan; Lee, Byeongmoon; Oh, Eunho; Kim, Hyunjong; Kim, Sangwoo; Lee, Seunghwan; Hong, Yongtaek

2017-03-01

Rapid growth of stretchable electronics stimulates broad uses in multidisciplinary fields as well as industrial applications. However, existing technologies are unsuitable for implementing versatile applications involving adaptable system design and functions in a cost/time-effective way because of vacuum-conditioned, lithographically-predefined processes. Here, we present a methodology for a fully printable, strain-engineered electronic wrap as a universal strategy which makes it more feasible to implement various stretchable electronic systems with customizable layouts and functions. The key aspects involve inkjet-printed rigid island (PRI)-based stretchable platform technology and corresponding printing-based automated electronic functionalization methodology, the combination of which provides fully printed, customized layouts of stretchable electronic systems with simplified process. Specifically, well-controlled contact line pinning effect of printed polymer solution enables the formation of PRIs with tunable thickness; and surface strain analysis on those PRIs leads to the optimized stability and device-to-island fill factor of strain-engineered electronic wraps. Moreover, core techniques of image-based automated pinpointing, surface-mountable device based electronic functionalizing, and one-step interconnection networking of PRIs enable customized circuit design and adaptable functionalities. To exhibit the universality of our approach, multiple types of practical applications ranging from self-computable digital logics to display and sensor system are demonstrated on skin in a customized form.

Fully printable, strain-engineered electronic wrap for customizable soft electronics

PubMed Central

Byun, Junghwan; Lee, Byeongmoon; Oh, Eunho; Kim, Hyunjong; Kim, Sangwoo; Lee, Seunghwan; Hong, Yongtaek

2017-01-01

Rapid growth of stretchable electronics stimulates broad uses in multidisciplinary fields as well as industrial applications. However, existing technologies are unsuitable for implementing versatile applications involving adaptable system design and functions in a cost/time-effective way because of vacuum-conditioned, lithographically-predefined processes. Here, we present a methodology for a fully printable, strain-engineered electronic wrap as a universal strategy which makes it more feasible to implement various stretchable electronic systems with customizable layouts and functions. The key aspects involve inkjet-printed rigid island (PRI)-based stretchable platform technology and corresponding printing-based automated electronic functionalization methodology, the combination of which provides fully printed, customized layouts of stretchable electronic systems with simplified process. Specifically, well-controlled contact line pinning effect of printed polymer solution enables the formation of PRIs with tunable thickness; and surface strain analysis on those PRIs leads to the optimized stability and device-to-island fill factor of strain-engineered electronic wraps. Moreover, core techniques of image-based automated pinpointing, surface-mountable device based electronic functionalizing, and one-step interconnection networking of PRIs enable customized circuit design and adaptable functionalities. To exhibit the universality of our approach, multiple types of practical applications ranging from self-computable digital logics to display and sensor system are demonstrated on skin in a customized form. PMID:28338055

Effects of mould on electrochemical migration behaviour of immersion silver finished printed circuit board.

PubMed

Yi, Pan; Xiao, Kui; Dong, Chaofang; Zou, Shiwen; Li, Xiaogang

2018-02-01

The role played by mould in the electrochemical migration (ECM) behaviour of an immersion silver finished printed circuit board (PCB-ImAg) under a direct current (DC) bias was investigated. An interesting phenomenon is found whereby mould, especially Aspergillus niger, can preferentially grow well on PCB-ImAg under electrical bias and then bridge integrated circuits and form a migration path. The cooperation of the mould and DC bias aggravates the ECM process occurring on PCB-ImAg. When the bias voltage is below 15V, ECM almost does not occur for Ag coating. Mechanisms that explain the ECM processes of PCB-ImAg in the presence of mould and DC bias are proposed. Copyright © 2017. Published by Elsevier B.V.

Beam forming network

NASA Technical Reports Server (NTRS)

Cramer, P. W., Jr. (Inventor)

1985-01-01

The network, which is connected to a layer of 134 feed elements that transmit and receive microwaves, consists of a pair of circuit boards parallel to the feed element layer. One of the two boards has 87 dividers that each divide a signal to be transmitted into seven portions, and the other board has 134 combiners that each collect seven transmit signal portions and deliver the sum to one of the feed elements. A similar arrangement is used to handle received signals. The large number of interconnections are made by printed circuit conductors radiating from each of the numerous dividers and combiners, and by providing interconnection pins that interconnect the ends of pairs of conductors lying on the two boards. The printed circuit conductors extend in undulating paths that provide maximum separation of conductors to minimize crosstalk.

Packaging Technologies for High Temperature Electronics and Sensors

NASA Technical Reports Server (NTRS)

Chen, Liang-Yu; Hunter, Gary W.; Neudeck, Philip G.; Beheim, Glenn M.; Spry, David J.; Meredith, Roger D.

2013-01-01

This paper reviews ceramic substrates and thick-film metallization based packaging technologies in development for 500 C silicon carbide (SiC) electronics and sensors. Prototype high temperature ceramic chip-level packages and printed circuit boards (PCBs) based on ceramic substrates of aluminum oxide (Al2O3) and aluminum nitride (AlN) have been designed and fabricated. These ceramic substrate-based chip-level packages with gold (Au) thick-film metallization have been electrically characterized at temperatures up to 550 C. A 96% alumina based edge connector for a PCB level subsystem interconnection has also been demonstrated recently. The 96% alumina packaging system composed of chip-level packages and PCBs has been tested with high temperature SiC devices at 500 C for over 10,000 hours. In addition to tests in a laboratory environment, a SiC JFET with a packaging system composed of a 96% alumina chip-level package and an alumina printed circuit board mounted on a data acquisition circuit board was launched as a part of the MISSE-7 suite to the International Space Station via a Shuttle mission. This packaged SiC transistor was successfully tested in orbit for eighteen months. A spark-plug type sensor package designed for high temperature SiC capacitive pressure sensors was developed. This sensor package combines the high temperature interconnection system with a commercial high temperature high pressure stainless steel seal gland (electrical feed-through). Test results of a packaged high temperature capacitive pressure sensor at 500 C are also discussed. In addition to the pressure sensor package, efforts for packaging high temperature SiC diode-based gas chemical sensors are in process.

Packaging Technologies for High Temperature Electronics and Sensors

NASA Technical Reports Server (NTRS)

Chen, Liangyu; Hunter, Gary W.; Neudeck, Philip G.; Beheim, Glenn M.; Spry, David J.; Meredith, Roger D.

2013-01-01

This paper reviews ceramic substrates and thick-film metallization based packaging technologies in development for 500degC silicon carbide (SiC) electronics and sensors. Prototype high temperature ceramic chip-level packages and printed circuit boards (PCBs) based on ceramic substrates of aluminum oxide (Al2O3) and aluminum nitride (AlN) have been designed and fabricated. These ceramic substrate-based chiplevel packages with gold (Au) thick-film metallization have been electrically characterized at temperatures up to 550degC. A 96% alumina based edge connector for a PCB level subsystem interconnection has also been demonstrated recently. The 96% alumina packaging system composed of chip-level packages and PCBs has been tested with high temperature SiC devices at 500degC for over 10,000 hours. In addition to tests in a laboratory environment, a SiC JFET with a packaging system composed of a 96% alumina chip-level package and an alumina printed circuit board mounted on a data acquisition circuit board was launched as a part of the MISSE-7 suite to the International Space Station via a Shuttle mission. This packaged SiC transistor was successfully tested in orbit for eighteen months. A spark-plug type sensor package designed for high temperature SiC capacitive pressure sensors was developed. This sensor package combines the high temperature interconnection system with a commercial high temperature high pressure stainless steel seal gland (electrical feed-through). Test results of a packaged high temperature capacitive pressure sensor at 500degC are also discussed. In addition to the pressure sensor package, efforts for packaging high temperature SiC diode-based gas chemical sensors are in process.

Toward Wireless Health Monitoring via an Analog Signal Compression-Based Biosensing Platform.

PubMed

Zhao, Xueyuan; Sadhu, Vidyasagar; Le, Tuan; Pompili, Dario; Javanmard, Mehdi

2018-06-01

Wireless all-analog biosensor design for the concurrent microfluidic and physiological signal monitoring is presented in this paper. The key component is an all-analog circuit capable of compressing two analog sources into one analog signal by the analog joint source-channel coding (AJSCC). Two circuit designs are discussed, including the stacked-voltage-controlled voltage source (VCVS) design with the fixed number of levels, and an improved design, which supports a flexible number of AJSCC levels. Experimental results are presented on the wireless biosensor prototype, composed of printed circuit board realizations of the stacked-VCVS design. Furthermore, circuit simulation and wireless link simulation results are presented on the improved design. Results indicate that the proposed wireless biosensor is well suited for sensing two biological signals simultaneously with high accuracy, and can be applied to a wide variety of low-power and low-cost wireless continuous health monitoring applications.

Printed circuit dispersive transmission line

DOEpatents

Ikezi, H.; Lin-Liu, Y.R.; DeGrassie, J.S.

1991-08-27

A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other. 5 figures.

Eddy current gauge for monitoring displacement using printed circuit coil

DOEpatents

Visioli, Jr., Armando J.

1977-01-01

A proximity detection system for non-contact displacement and proximity measurement of static or dynamic metallic or conductive surfaces is provided wherein the measurement is obtained by monitoring the change in impedance of a flat, generally spiral-wound, printed circuit coil which is excited by a constant current, constant frequency source. The change in impedance, which is detected as a corresponding change in voltage across the coil, is related to the eddy current losses in the distant conductive material target. The arrangement provides for considerable linear displacement range with increased accuracies, stability, and sensitivity over the entire range.

Aerosol jet printed p- and n-type electrolyte-gated transistors with a variety of electrode materials: exploring practical routes to printed electronics.

PubMed

Hong, Kihyon; Kim, Se Hyun; Mahajan, Ankit; Frisbie, C Daniel

2014-11-12

Printing electrically functional liquid inks is a promising approach for achieving low-cost, large-area, additive manufacturing of flexible electronic circuits. To print thin-film transistors, a basic building block of thin-film electronics, it is important to have several options for printable electrode materials that exhibit high conductivity, high stability, and low-cost. Here we report completely aerosol jet printed (AJP) p- and n-type electrolyte-gated transistors (EGTs) using a variety of different electrode materials including highly conductive metal nanoparticles (Ag), conducting polymers (polystyrenesulfonate doped poly(3,4-ethylendedioxythiophene, PEDOT:PSS), transparent conducting oxides (indium tin oxide), and carbon-based materials (reduced graphene oxide). Using these source-drain electrode materials and a PEDOT:PSS/ion gel gate stack, we demonstrated all-printed p- and n-type EGTs in combination with poly(3-hexythiophene) and ZnO semiconductors. All transistor components (including electrodes, semiconductors, and gate insulators) were printed by AJP. Both kinds of devices showed typical p- and n-type transistor characteristics, and exhibited both low-threshold voltages (<2 V) and high hole and electron mobilities. Our assessment suggests Ag electrodes may be the best option in terms of overall performance for both types of EGTs.

Paper-based piezoelectric touch pads with hydrothermally grown zinc oxide nanowires.

PubMed

Li, Xiao; Wang, Yu-Hsuan; Zhao, Chen; Liu, Xinyu

2014-12-24

This paper describes a new type of paper-based piezoelectric touch pad integrating zinc oxide nanowires (ZnO NWs), which can serve as user interfaces in paper-based electronics. The sensing functionality of these touch pads is enabled by the piezoelectric property of ZnO NWs grown on paper using a simple, cost-efficient hydrothermal method. A piece of ZnO-NW paper with two screen-printed silver electrodes forms a touch button, and touch-induced electric charges from the button are converted into a voltage output using a charge amplifier circuit. A touch pad consisting of an array of buttons can be readily integrated into paper-based electronic devices, allowing user input of information for various purposes such as programming, identification checking, and gaming. This novel design features ease of fabrication, low cost, ultrathin structure, and good compatibility with techniques in printed electronics, and further enriches the available technologies of paper-based electronics.

Design of a signal conditioner for the Fermilab Magnet Test Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giannelli, Pietro

2012-01-01

This thesis describes the design of a remotely-programmable signal conditioner for the harmonic measurement of accelerator magnets. A 10-channel signal conditioning circuit featuring bucking capabilities was designed from scratch and implemented to the level of the printed circuit board layout. Other system components were chosen from those available on the market. Software design was started with the definition of routine procedures. This thesis is part of an upgrade project for replacing obsolescent automated test equipment belonging to the Fermilab Magnet Test Facility. The design started with a given set of requirements. Using a top-down approach, all the circuits were designedmore » and their expected performances were theoretically predicted and simulated. A limited prototyping phase followed. The printed circuit boards were laid out and routed using a CAD software and focusing the design on maximum electromagnetic interference immunity. An embedded board was selected for controlling and interfacing the signal conditioning circuitry with the instrumentation network. Basic low level routines for hardware access were defined. This work covered the entire design process of the signal conditioner, resulting in a project ready for manufacturing. The expected performances are in line with the requirements and, in the cases where this was not possible, approval of trade-offs was sought and received from the end users. Part I deals with the global structure of the signal conditioner and the subdivision in functional macro-blocks. Part II treats the hardware design phase in detail, covering the analog and digital circuits, the printed circuit layouts, the embedded controller and the power supply selection. Part III deals with the basic hardware-related routines to be implemented in the final software.« less

Liter Flow and Mix Selection in Semiclosed-Circuit Scuba

DTIC Science & Technology

1970-01-27

iCUII*. TO USE IT& JUST MNSWER 130 PRINT "INC OUSTIfWS AS IIIEY APPEAR*’ 130 PRINT 340 PRIN’ ISO PRINT MAXIMUM @11 USAGSE LW sees IŔ INPUT US 170 PRINT...34MINIMUM 03 UISAM "i NODS ISO INPUT U4 90Itoli U4bs 113 10 It0 too "i ISO35 310 PRINT 310 PRINT "ETRY MI STAKE* TNT AGAIN" too PRINT SAI0 as To ISO ...113049 S600467 30 4.79063 5.14876 7047556 so 6.32109 6.98531 10.506 T0 IeSSISS lst’$$IS5 11352 t00 10.1472 1.657,6-1 14.0871 too 1707995 10. 79P 4

Portable Cytometry Using Microscale Electronic Sensing

PubMed Central

Emaminejad, Sam; Paik, Kee-Hyun; Tabard-Cossa, Vincent; Javanmard, Mehdi

2015-01-01

In this manuscript, we present three different micro-impedance sensing architectures for electronic counting of cells and beads. The first method of sensing is based on using an open circuit sensing electrode integrated in a micro-pore, which measures the shift in potential as a micron-sized particle passes through. Our micro-pore, based on a funnel shaped microchannel, was fabricated in PDMS and was bound covalently to a glass substrate patterned with a gold open circuit electrode. The amplification circuitry was integrated onto a battery-powered custom printed circuit board. The second method is based on a three electrode differential measurement, which opens up the potential of using signal processing techniques to increase signal to noise ratio post measurement. The third architecture uses a contactless sensing approach, which significantly minimizes the cost of the consumable component of the impedance cytometer. We demonstrated proof of concept for the three sensing architectures by measuring the detected signal due to the passage of micron sized beads through the pore. PMID:27647950

Nanosilver conductive ink: A case study for evaluating the potential risk of nanotechnology under hypothetical use scenarios.

PubMed

Martin, David P; Melby, Nicolas L; Jordan, Shinita M; Bednar, Anthony J; Kennedy, Alan J; Negrete, Maria E; Chappell, Mark A; Poda, Aimee R

2016-11-01

Engineered nanomaterials (ENMs) are being incorporated into a variety of consumer products due to unique properties that offer a variety of advantages over bulk materials. Understanding of the nano-specific risk associated with nano-enabled technologies, however, continues to lag behind research and development, registration with regulators, and commercialization. One example of a nano-enabled technology is nanosilver ink, which can be used in commercial ink-jet printers for the development of low-cost printable electronics. This investigation utilizes a tiered EHS framework to evaluate the potential nano-specific release, exposure and hazard associated with typical use of both nanosilver ink and printed circuits. The framework guides determination of the potential for ENM release from both forms of the technology in simulated use scenarios, including spilling of the ink, aqueous release (washing) from the circuits and UV light exposure. The as-supplied ink merits nano-specific consideration based on the presence of nanoparticles and their persistence in environmentally-relevant media. The material released from the printed circuits upon aqueous exposure was characterized by a number of analysis techniques, including ultracentrifugation and single particle ICP-MS, and the results suggest that a vast majority of the material was ionic in nature and nano-specific regulatory scrutiny may be less relevant. Published by Elsevier Ltd.

A cytokine immunosensor for Multiple Sclerosis detection based upon label-free electrochemical impedance spectroscopy using electroplated printed circuit board electrodes.

PubMed

Bhavsar, Kinjal; Fairchild, Aaron; Alonas, Eric; Bishop, Daniel K; La Belle, Jeffrey T; Sweeney, James; Alford, T L; Joshi, Lokesh

2009-10-15

A biosensor for the serum cytokine, Interleukin-12 (IL-12), based upon a label-free electrochemical impedance spectroscopy (EIS) monitoring approach is described. Overexpression of IL-12 has been correlated to the diagnosis of Multiple Sclerosis (MS). An immunosensor has been fabricated by electroplating gold onto a disposable printed circuit board (PCB) electrode and immobilizing anti-IL-12 monoclonal antibodies (MAb) onto the surface of the electrode. This approach yields a robust sensor that facilitates reproducible mass fabrication and easy alteration of the electrode shape. Results indicate that this novel PCB sensor can detect IL-12 at physiological levels, <100 fM with f-values of 0.05 (typically <0.0001) in a label-free and rapid manner. A linear (with respect to log concentration) detectable range was achieved. Detection in a complex biological solution is also explored; however, significant loss of dynamic range is noted in the 100% complex solution. The cost effective approach described here can be used potentially for diagnosis of diseases (like MS) with known biomarkers in body fluids and for monitoring physiological levels of biomolecules with healthcare, food, and environmental relevance.

Optomechanical Design and Characterization of a Printed-Circuit-Board-Based Free-Space Optical Interconnect Package

NASA Astrophysics Data System (ADS)

Zheng, Xuezhe; Marchand, Philippe J.; Huang, Dawei; Kibar, Osman; Ozkan, Nur S. E.; Esener, Sadik C.

1999-09-01

We present a proof of concept and a feasibility demonstration of a practical packaging approach in which free-space optical interconnects (FSOI s) can be integrated simply on electronic multichip modules (MCM s) for intra-MCM board interconnects. Our system-level packaging architecture is based on a modified folded 4 f imaging system that has been implemented with only off-the-shelf optics, conventional electronic packaging, and passive-assembly techniques to yield a potentially low-cost and manufacturable packaging solution. The prototypical system as built supports 48 independent FSOI channels with 8 separate laser and detector chips, for which each chip consists of a one-dimensional array of 12 devices. All the chips are assembled on a single substrate that consists of a printed circuit board or a ceramic MCM. Optical link channel efficiencies of greater than 90% and interchannel cross talk of less than 20 dB at low frequency have been measured. The system is compact at only 10 in. 3 (25.4 cm 3 ) and is scalable, as it can easily accommodate additional chips as well as two-dimensional optoelectronic device arrays for increased interconnection density.

Graphene Ink Laminate Structures on Poly(vinylidene difluoride) (PVDF) for Pyroelectric Thermal Energy Harvesting and Waste Heat Recovery.

PubMed

Zabek, Daniel; Seunarine, Kris; Spacie, Chris; Bowen, Chris

2017-03-15

Thermal energy can be effectively converted into electricity using pyroelectrics, which act as small scale power generator and energy harvesters providing nanowatts to milliwatts of electrical power. In this paper, a novel pyroelectric harvester based on free-standing poly(vinylidene difluoride) (PVDF) was manufactured that exploits the high thermal radiation absorbance of a screen printed graphene ink electrode structure to facilitate the conversion of the available thermal radiation energy into electrical energy. The use of interconnected graphene nanoplatelets (GNPs) as an electrode enable high thermal radiation absorbance and high electrical conductivity along with the ease of deposition using a screen print technique. For the asymmetric structure, the pyroelectric open-circuit voltage and closed-circuit current were measured, and the harvested electrical energy was stored in an external capacitor. For the graphene ink/PVDF/aluminum system the closed circuit pyroelectric current improves by 7.5 times, the open circuit voltage by 3.4 times, and the harvested energy by 25 times compared to a standard aluminum/PVDF/aluminum system electrode design, with a peak energy density of 1.13 μJ/cm 3 . For the pyroelectric device employed in this work, a complete manufacturing process and device characterization of these structures are reported along with the thermal conductivity of the graphene ink. The material combination presented here provides a new approach for delivering smart materials and structures, wireless technologies, and Internet of Things (IoT) devices.

Reversible Conversion of Dominant Polarity in Ambipolar Polymer/Graphene Oxide Hybrids

PubMed Central

Zhou, Ye; Han, Su-Ting; Sonar, Prashant; Ma, Xinlei; Chen, Jihua; Zheng, Zijian; Roy, V. A. L.

2015-01-01

The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. This hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits. PMID:25801827

3D printed magnetic polymer composite transformers

NASA Astrophysics Data System (ADS)

Bollig, Lindsey M.; Hilpisch, Peter J.; Mowry, Greg S.; Nelson-Cheeseman, Brittany B.

2017-11-01

The possibility of 3D printing a transformer core using fused deposition modeling methods is explored. With the use of additive manufacturing, ideal transformer core geometries can be achieved in order to produce a more efficient transformer. In this work, different 3D printed settings and toroidal geometries are tested using a custom integrated magnetic circuit capable of measuring the hysteresis loop of a transformer. These different properties are then characterized, and it was determined the most effective 3D printed transformer core requires a high fill factor along with a high concentration of magnetic particulate.

Selective thermal transformation of old computer printed circuit boards to Cu-Sn based alloy.

PubMed

Shokri, Ali; Pahlevani, Farshid; Cole, Ivan; Sahajwalla, Veena

2017-09-01

This study investigates, verifies and determines the optimal parameters for the selective thermal transformation of problematic electronic waste (e-waste) to produce value-added copper-tin (Cu-Sn) based alloys; thereby demonstrating a novel new pathway for the cost-effective recovery of resources from one of the world's fastest growing and most challenging waste streams. Using outdated computer printed circuit boards (PCBs), a ubiquitous component of e-waste, we investigated transformations across a range of temperatures and time frames. Results indicate a two-step heat treatment process, using a low temperature step followed by a high temperature step, can be used to produce and separate off, first, a lead (Pb) based alloy and, subsequently, a Cu-Sn based alloy. We also found a single-step heat treatment process at a moderate temperature of 900 °C can be used to directly transform old PCBs to produce a Cu-Sn based alloy, while capturing the Pb and antimony (Sb) as alloying elements to prevent the emission of these low melting point elements. These results demonstrate old computer PCBs, large volumes of which are already within global waste stockpiles, can be considered a potential source of value-added metal alloys, opening up a new opportunity for utilizing e-waste to produce metal alloys in local micro-factories. Copyright © 2017 Elsevier Ltd. All rights reserved.

CMOS Imaging of Temperature Effects on Pin-Printed Xerogel Sensor Microarrays.

PubMed

Lei Yao; Ka Yi Yung; Chodavarapu, Vamsy P; Bright, Frank V

2011-04-01

In this paper, we study the effect of temperature on the operation and performance of a xerogel-based sensor microarrays coupled to a complementary metal-oxide semiconductor (CMOS) imager integrated circuit (IC) that images the photoluminescence response from the sensor microarray. The CMOS imager uses a 32 × 32 (1024 elements) array of active pixel sensors and each pixel includes a high-gain phototransistor to convert the detected optical signals into electrical currents. A correlated double sampling circuit and pixel address/digital control/signal integration circuit are also implemented on-chip. The CMOS imager data are read out as a serial coded signal. The sensor system uses a light-emitting diode to excite target analyte responsive organometallic luminophores doped within discrete xerogel-based sensor elements. As a proto type, we developed a 3 × 3 (9 elements) array of oxygen (O2) sensors. Each group of three sensor elements in the array (arranged in a column) is designed to provide a different and specific sensitivity to the target gaseous O2 concentration. This property of multiple sensitivities is achieved by using a mix of two O2 sensitive luminophores in each pin-printed xerogel sensor element. The CMOS imager is designed to be low noise and consumes a static power of 320.4 μW and an average dynamic power of 624.6 μW when operating at 100-Hz sampling frequency and 1.8-V dc power supply.

Hybrid stretchable circuits on silicone substrate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, A., E-mail: adam.1.robinson@nokia.com; Aziz, A., E-mail: a.aziz1@lancaster.ac.uk; Liu, Q.

When rigid and stretchable components are integrated onto a single elastic carrier substrate, large strain heterogeneities appear in the vicinity of the deformable-non-deformable interfaces. In this paper, we report on a generic approach to manufacture hybrid stretchable circuits where commercial electronic components can be mounted on a stretchable circuit board. Similar to printed circuit board development, the components are electrically bonded on the elastic substrate and interconnected with stretchable electrical traces. The substrate—a silicone matrix carrying concentric rigid disks—ensures both the circuit elasticity and the mechanical integrity of the most fragile materials.

Flexible Packaging by Film-Assisted Molding for Microintegration of Inertia Sensors

PubMed Central

Hera, Daniel; Berndt, Armin; Günther, Thomas; Schmiel, Stephan; Harendt, Christine; Zimmermann, André

2017-01-01

Packaging represents an important part in the microintegration of sensors based on microelectromechanical system (MEMS). Besides miniaturization and integration density, functionality and reliability in combination with flexibility in packaging design at moderate costs and consequently high-mix, low-volume production are the main requirements for future solutions in packaging. This study investigates possibilities employing printed circuit board (PCB-)based assemblies to provide high flexibility for circuit designs together with film-assisted transfer molding (FAM) to package sensors. The feasibility of FAM in combination with PCB and MEMS as a packaging technology for highly sensitive inertia sensors is being demonstrated. The results prove the technology to be a viable method for damage-free packaging of stress- and pressure-sensitive MEMS. PMID:28653992

A Simple Picaxe Microcontroller Pulse Source for Juxtacellular Neuronal Labelling †

PubMed Central

Verberne, Anthony J. M.

2016-01-01

Juxtacellular neuronal labelling is a method which allows neurophysiologists to fill physiologically-identified neurons with small positively-charged marker molecules. Labelled neurons are identified by histochemical processing of brain sections along with immunohistochemical identification of neuropeptides, neurotransmitters, neurotransmitter transporters or biosynthetic enzymes. A microcontroller-based pulser circuit and associated BASIC software script is described for incorporation into the design of a commercially-available intracellular electrometer for use in juxtacellular neuronal labelling. Printed circuit board construction has been used for reliability and reproducibility. The current design obviates the need for a separate digital pulse source and simplifies the juxtacellular neuronal labelling procedure. PMID:28952589

Housing And Mounting Structure

DOEpatents

Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R.F.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Miller, Gregory V.; Peterson, David W.; Smith, Terrance T.

2005-03-08

This invention relates to an optical transmitter, receiver or transceiver module, and more particularly, to an apparatus for connecting a first optical connector to a second optical connector. The apparatus comprises: (1) a housing having at least a first end and at least a second end, the first end of the housing capable of receiving the first optical connector, and the second end of the housing capable of receiving the second optical connector; (2) a longitudinal cavity extending from the first end of the housing to the second end of the housing; and (3) an electromagnetic shield comprising at least a portion of the housing. This invention also relates to an apparatus for housing a flexible printed circuit board, and this apparatus comprises: (1) a mounting structure having at least a first surface and a second surface; (2) alignment ridges along the first and second surfaces of the mounting structure, the alignment ridges functioning to align and secure a flexible printed circuit board that is wrapped around and attached to the first and second surfaces of the mounting structure; and (3) a series of heat sink ridges adapted to the mounting structure, the heat sink ridges functioning to dissipate heat that is generated from the flexible printed circuit board.

Toward environmentally-benign utilization of nonmetallic fraction of waste printed circuit boards as modifier and precursor.

PubMed

Hadi, Pejman; Ning, Chao; Ouyang, Weiyi; Xu, Meng; Lin, Carol S K; McKay, Gordon

2015-01-01

Electronic waste, including printed circuit boards, is growing at an alarming rate due to the accelerated technological progress and the shorter lifespan of the electronic equipment. In the past decades, due to the lack of proper economic and environmentally-benign recycling technologies, a major fraction of e-waste generated was either destined to landfills or incinerated with the sole intention of its disposal disregarding the toxic nature of this waste. Recently, with the increasing public awareness over their environment and health issues and with the enaction of more stringent regulations, environmentally-benign recycling has been driven to be an alternative option partially replacing the traditional eco-unfriendly disposal methods. One of the most favorable green technologies has been the mechanical separation of the metallic and nonmetallic fraction of the waste printed circuit boards. Although metallic fraction, as the most profitable component, is used to generate the revenue of the separation process, the nonmetallic fraction (NMF) has been left isolated. Herein, the recent developments in the application of NMF have been comprehensively reviewed and an eco-friendly emerging usage of NMF as a value-added material for sustainable remediation has been introduced. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sensor fusion of phase measuring profilometry and stereo vision for three-dimensional inspection of electronic components assembled on printed circuit boards.

PubMed

Hong, Deokhwa; Lee, Hyunki; Kim, Min Young; Cho, Hyungsuck; Moon, Jeon Il

2009-07-20

Automatic optical inspection (AOI) for printed circuit board (PCB) assembly plays a very important role in modern electronics manufacturing industries. Well-developed inspection machines in each assembly process are required to ensure the manufacturing quality of the electronics products. However, generally almost all AOI machines are based on 2D image-analysis technology. In this paper, a 3D-measurement-method-based AOI system is proposed consisting of a phase shifting profilometer and a stereo vision system for assembled electronic components on a PCB after component mounting and the reflow process. In this system information from two visual systems is fused to extend the shape measurement range limited by 2pi phase ambiguity of the phase shifting profilometer, and finally to maintain fine measurement resolution and high accuracy of the phase shifting profilometer with the measurement range extended by the stereo vision. The main purpose is to overcome the low inspection reliability problem of 2D-based inspection machines by using 3D information of components. The 3D shape measurement results on PCB-mounted electronic components are shown and compared with results from contact and noncontact 3D measuring machines. Based on a series of experiments, the usefulness of the proposed sensor system and its fusion technique are discussed and analyzed in detail.

Morphological Behavior of Printed Silver Electrodes with Protective Self-Assembled Monolayers for Electrochemical Migration.

PubMed

Sekine, Tomohito; Sato, Jun; Takeda, Yasunori; Kumaki, Daisuke; Tokito, Shizuo

2018-05-09

We evaluated the electrochemical behaviors and reliability of printed silver (Ag) electrodes prepared from nanoparticle inks with the use of protective self-assembled monolayers (SAMs) under electronic bias conditions. The printed Ag electrodes were fabricated by inkjet printing on a hydrophobic substrate. The SAMs, which acted as barriers to moisture, were prepared by immersing the substrate in a pentafluorobenzenethiol solution at ambient temperature (25 °C). We investigated the electrochemical migration phenomenon using the water drop method, and the results showed that the formation of dendrites connecting the cathode and the anode, which can affect the electrochemical reliability of an electric device, was suppressed in the presence of the SAMs. The time before short circuit occurred was found to depend on the spacing between the electrodes, i.e., 130 s, when the distance between the electrodes was 200 μm in the presence of an SAM. We demonstrated that Ag electrodes treated using the procedure described in this work suppress the occurrence of electrical short circuits caused by Ag dendrite formation and thus their electrochemical properties are substantially improved.

Interferometric surface mapping with variable sensitivity.

PubMed

Jaerisch, W; Makosch, G

1978-03-01

In the photolithographic process, presently employed for the production of integrated circuits, sets of correlated masks are used for exposing the photoresist on silicon wafers. Various sets of masks which are printed in different printing tools must be aligned correctly with respect to the structures produced on the wafer in previous process steps. Even when perfect alignment is considered, displacements and distortions of the printed wafer patterns occur. They are caused by imperfections of the printing tools or/and wafer deformations resulting from high temperature processes. Since the electrical properties of the final integrated circuits and therefore the manufacturing yield depend to a great extent on the precision at which such patterns are superimposed, simple and fast overlay measurements and flatness measurements as well are very important in IC-manufacturing. A simple optical interference method for flatness measurements will be described which can be used under manufacturing conditions. This method permits testing of surface height variations by nearly grazing light incidence by absence of a physical reference plane. It can be applied to polished surfaces and rough surfaces as well.

Laser-Assisted Reduction of Highly Conductive Circuits Based on Copper Nitrate for Flexible Printed Sensors

NASA Astrophysics Data System (ADS)

Bai, Shi; Zhang, Shigang; Zhou, Weiping; Ma, Delong; Ma, Ying; Joshi, Pooran; Hu, Anming

2017-10-01

Stretchable electronic sensing devices are defining the path toward wearable electronics. High-performance flexible strain sensors attached on clothing or human skin are required for potential applications in the entertainment, health monitoring, and medical care sectors. In this work, conducting copper electrodes were fabricated on polydimethylsiloxane as sensitive stretchable microsensors by integrating laser direct writing and transfer printing approaches. The copper electrode was reduced from copper salt using laser writing rather than the general approach of printing with pre-synthesized copper or copper oxide nanoparticles. An electrical resistivity of 96 μΩ cm was achieved on 40-μm-thick Cu electrodes on flexible substrates. The motion sensing functionality successfully demonstrated a high sensitivity and mechanical robustness. This in situ fabrication method leads to a path toward electronic devices on flexible substrates.[Figure not available: see fulltext.

Modular control subsystems for use in solar heating systems for multi-family dwellings

NASA Technical Reports Server (NTRS)

1977-01-01

Progress in the development of solar heating modular control subsystems is reported. Circuit design, circuit drawings, and printed circuit board layout are discussed along with maintenance manuals, installation instructions, and verification and acceptance tests. Calculations made to determine the predicted performance of the differential thermostat are given including details and results of tests for the offset temperature, and boil and freeze protect points.

[Electric short-circuit incident observed with "Upsher" laryngoscopes].

PubMed

Tritsch, L; Vailly, B

2006-01-01

We observed an electrical short-circuit between a fasten screw of the printed circuit and the handle of an Upsher universal laryngoscope (serial number UQ1). The isolating Silicone layer was broken above the screw. This isolation defect was found all over our Upsher laryngoscopes of the UQ1 series. No doubt that if accumulators were used instead of batteries, emitted heat would be in largest amount and perhaps dangerous.

Phoenix Interferometer

DTIC Science & Technology

1975-06-01

proportioning circuit , Triac , and heater blankets. The significant features of the temperature controllers are small size, less than one half per...interferometer. The only change to the Firebird system needed to ac- commodate the new sensor is the replacement of several circuit boards. No hard wiring or...temperature at altitude (220oK). In addition to the sensor head, the Phoe- nix system also includes a set of plug-in printed circuit cards which

Effect of Bypass Capacitor in Common-mode Noise Reduction Technique for Automobile PCB

NASA Astrophysics Data System (ADS)

Uno, Takanori; Ichikawa, Kouji; Mabuchi, Yuichi; Nakamura, Atushi

In this letter, we studied the use of common mode noise reduction technique for in-vehicle electronic equipment, each comprising large-scale integrated circuit (LSI), printed circuit board (PCB), wiring harnesses, and ground plane. We have improved the model circuit of the common mode noise that flows to the wire harness to add the effect of by-pass capacitors located near an LSI.

A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines

PubMed Central

Liu, Yadong; Xie, Xiaolei; Hu, Yue; Qian, Yong; Sheng, Gehao; Jiang, Xiuchen

2016-01-01

The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices. PMID:27213402

Flexible printed circuit board actuators

NASA Astrophysics Data System (ADS)

Lee, Junseok; Cha, Youngsu

2017-12-01

Out-of-plane actuators are made possible by the breaking of planar symmetry. In this paper, we present a thin-film out-of-plane electrostatic actuator for a flexible printed circuit board (FPCB) that can be fabricated with a single step of the conventional manufacturing process. No other components are required for actuation except a single sheet of the FPCB, and it works based on the planar asymmetry resulting from asymmetrically patterned top and bottom electrodes on each side of the polyimide film. With the structural asymmetry, the application of a high voltage in the order of kilovolts results in the asymmetry of the electric fields and the body force density, which generates the bending moment that leads to macroscopic deformations. We applied the finite element method to examine the asymmetry induced by the difference in the electrodes. In the experiment, the displacement responses to step input and square wave input of various frequencies were analyzed. It was found that our actuator constitutes an underdamped system, exhibiting resonance characteristics. The maximum oscillatory amplitude was determined at resonance, and the relationship between the displacement and the applied voltage was investigated.

Roughness measurements on coupling structures for optical interconnections integrated on a printed circuit board

NASA Astrophysics Data System (ADS)

Hendrickx, Nina; Van Erps, Jürgen; Suyal, Himanshu; Taghizadeh, Mohammad; Thienpont, Hugo; Van Daele, Peter

2006-04-01

In this paper, laser ablation (at UGent), deep proton writing (at VUB) and laser direct writing (at HWU) are presented as versatile technologies that can be used for the fabrication of coupling structures for optical interconnections integrated on a printed circuit board (PCB). The optical layer, a highly cross-linked acrylate based polymer, is applied on an FR4 substrate. Both laser ablation and laser direct writing are used for the definition of arrays of multimode optical waveguides, which guide the light in the plane of the optical layer. In order to couple light vertically in/out of the plane of the optical waveguides, coupling structures have to be integrated into the optical layer. Out-of-plane turning mirrors, that deflect the light beam over 90°, are used for this purpose. The surface roughness and angle of three mirror configurations are evaluated: a laser ablated one that is integrated into the optical waveguide, a laser direct written one that is also directly written onto the waveguide and a DPW insert that is plugged into a cavity into the waveguiding layer.

Copper recovery and gold enrichment from waste printed circuit boards by mediated electrochemical oxidation.

PubMed

Fogarasi, Szabolcs; Imre-Lucaci, Florica; Imre-Lucaci, Arpád; Ilea, Petru

2014-05-30

The present study aims to develop an eco-friendly chemical-electrochemical process for the simultaneous recovery of copper and separation of a gold rich residue from waste printed circuit boards (WPCBs). The process was carried out by employing two different types of reactors coupled in series: a leaching reactor with a perforated rotating drum, for the dissolution of base metals and a divided electrochemical reactor for the regeneration of the leaching solution with the parallel electrowinning of copper. The process performances were evaluated on the basis of the dissolution efficiency, current efficiency and specific energy consumptions. Finally a process scale up was realized taking into consideration the optimal values of the operating parameters. The laboratory scale leaching plant allowed the recovery of a high purity copper deposit (99.04wt.%) at a current efficiency of 63.84% and specific energy consumption of 1.75kWh/kg cooper. The gold concentration in the remained solid residue was 25 times higher than the gold concentration in the initial WPCB samples. Copyright © 2014 Elsevier B.V. All rights reserved.

A Low-cost 4 Bit, 10 Giga-samples-per-second Analog-to-digital Converter Printed Circuit Board Assembly for FPGA-based Backends

NASA Astrophysics Data System (ADS)

Jiang, Homin; Yu, Chen-Yu; Kubo, Derek; Chen, Ming-Tang; Guzzino, Kim

2016-11-01

In this study, a 4 bit, 10 giga-samples-per-second analog-to-digital converter (ADC) printed circuit board assembly (PCBA) was designed, manufactured, and characterized for digitizing radio telescopes. For this purpose, an Adsantec ANST7120A-KMA flash ADC chip was used. Together with the field-programmable gate array platform, developed by the Collaboration for Astronomy Signal Processing and Electronics Research community, the PCBA enables data acquisition with a wide bandwidth and simplifies the intermediate frequency section. In the current version, the PCBA and the chip exhibit an analog bandwidth of 10 GHz (3 dB loss) and 20 GHz, respectively, which facilitates second, third, and even fourth Nyquist sampling. The following average performance parameters were obtained from the first and second Nyquist zones of the three boards: a spurious-free dynamic range of 31.35/30.45 dB, a signal-to-noise and distortion ratio of 22.95/21.83 dB, and an effective number of bits of 3.65/3.43, respectively.

Environmental risk assessment of wastewaters from printed circuit board production: A multibiomarker approach using human cells.

PubMed

Gerić, Marko; Gajski, Goran; Oreščanin, Višnja; Domijan, Ana-Marija; Kollar, Robert; Garaj-Vrhovac, Vera

2017-02-01

Since the production of printed circuit boards (PCBs) generates wastewater contaminated with heavy metals and organic matter, PCB factories represent potential pollution sites. The wastewater toxicologically tested in this study contained several metals and the most abundant were copper and iron. At two exposure times tested (4 and 24 h) PCB wastewater (PCBW) proved to be cytotoxic (decreased cell viability) and genotoxic (increased comet assay tail intensity and tail moment) to human blood peripheral lymphocytes in vitro, and the oxidative stress parameter (malondialdehyde concentration) was also found to be higher. After application of combined treatment by waste base, ozone and waste sludge methods, concentrations of metals in purified PCBW were below the upper permitted levels and all tested toxicological parameters did not differ compared to the negative control. Taken together, similar methods could be implemented in PCB factories before discharging potentially toxic wastewater into the environment because purified PCBW does not represent a threat from the aspect of cytotoxicity and genotoxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Separation and recovery of fine particles from waste circuit boards using an inflatable tapered diameter separation bed.

PubMed

Duan, Chenlong; Sheng, Cheng; Wu, Lingling; Zhao, Yuemin; He, Jinfeng; Zhou, Enhui

2014-01-01

Recovering particle materials from discarded printed circuit boards can enhance resource recycling and reduce environmental pollution. Efficiently physically separating and recovering fine metal particles (-0.5 mm) from the circuit boards are a key recycling challenge. To do this, a new type of separator, an inflatable tapered diameter separation bed, was developed to study particle motion and separation mechanisms in the bed's fluid flow field. For 0.5-0.25 mm circuit board particles, metal recovery rates ranged from 87.56 to 94.17%, and separation efficiencies ranged from 87.71 to 94.20%. For 0.25-0.125 mm particles, metal recovery rates ranged from 84.76 to 91.97%, and separation efficiencies ranged from 84.74 to 91.86%. For superfine products (-0.125 mm), metal recovery rates ranged from 73.11 to 83.04%, and separation efficiencies ranged from 73.00 to 83.14%. This research showed that the inflatable tapered diameter separation bed achieved efficient particle separation and can be used to recover fine particles under a wide range of operational conditions. The bed offers a new mechanical technology to recycle valuable materials from discarded printed circuit boards, reducing environmental pollution.

Quantitative analysis of peel-off degree for printed electronics

NASA Astrophysics Data System (ADS)

Park, Janghoon; Lee, Jongsu; Sung, Ki-Hak; Shin, Kee-Hyun; Kang, Hyunkyoo

2018-02-01

We suggest a facile methodology of peel-off degree evaluation by image processing on printed electronics. The quantification of peeled and printed areas was performed using open source programs. To verify the accuracy of methods, we manually removed areas from the printed circuit that was measured, resulting in 96.3% accuracy. The sintered patterns showed a decreasing tendency in accordance with the increase in the energy density of an infrared lamp, and the peel-off degree increased. Thus, the comparison between both results was presented. Finally, the correlation between performance characteristics was determined by quantitative analysis.

Reversible conversion of dominant polarity in ambipolar polymer/graphene oxide hybrids

DOE PAGES

Zhou, Ye; Han, Su -Ting; Sonar, Prashant; ...

2015-03-24

The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. Wemore » conclude that this hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits.« less

High density electrical card connector system

DOEpatents

Haggard, J. Eric; Trotter, Garrett R.

2000-01-01

An electrical circuit board card connection system is disclosed which comprises a wedge-operated locking mechanism disposed along an edge portion of the printed circuit board. An extrusion along the edge of the circuit board mates with an extrusion fixed to the card cage having a plurality of electrical connectors. The connection system allows the connectors to be held away from the circuit board during insertion/extraction and provides a constant mating force once the circuit board is positioned and the wedge inserted. The disclosed connection system is a simple solution to the need for a greater number of electrical signal connections.

Packaging printed circuit boards: A production application of interactive graphics

NASA Technical Reports Server (NTRS)

Perrill, W. A.

1975-01-01

The structure and use of an Interactive Graphics Packaging Program (IGPP), conceived to apply computer graphics to the design of packaging electronic circuits onto printed circuit boards (PCB), were described. The intent was to combine the data storage and manipulative power of the computer with the imaginative, intuitive power of a human designer. The hardware includes a CDC 6400 computer and two CDC 777 terminals with CRT screens, light pens, and keyboards. The program is written in FORTRAN 4 extended with the exception of a few functions coded in COMPASS (assembly language). The IGPP performs four major functions for the designer: (1) data input and display, (2) component placement (automatic or manual), (3) conductor path routing (automatic or manual), and (4) data output. The most complex PCB packaged to date measured 16.5 cm by 19 cm and contained 380 components, two layers of ground planes and four layers of conductors mixed with ground planes.

Cleaning of printed circuit assemblies with surface-mounted components

NASA Astrophysics Data System (ADS)

Arzigian, J. S.

The need for ever-increasing miniaturization of airborne instrumentation through the use of surface mounted components closely placed on printed circuit boards highlights problems with traditional board cleaning methods. The reliability of assemblies which have been cleaned with vapor degreasing and spray cleaning can be seriously compromised by residual contaminants leading to solder joint failure, board corrosion, and even electrical failure of the mounted parts. In addition, recent government actions to eliminate fully halogenated chlorofluorocarbons (CFC) and chlorinated hydrocarbons from the industrial environment require the development of new cleaning materials and techniques. This paper discusses alternative cleaning materials and techniques and results that can be expected with them. Particular emphasis is placed on problems related to surface-mounted parts. These new techniques may lead to improved circuit reliability and, at the same time, be less expensive and less environmentally hazardous than the traditional systems.

3D Printed Shock Mitigating Structures

NASA Astrophysics Data System (ADS)

Schrand, Amanda; Elston, Edwin; Dennis, Mitzi; Metroke, Tammy; Chen, Chenggang; Patton, Steven; Ganguli, Sabyasachi; Roy, Ajit

Here we explore the durability, and shock mitigating potential, of solid and cellular 3D printed polymers and conductive inks under high strain rate, compressive shock wave and high g acceleration conditions. Our initial designs include a simple circuit with 4 resistors embedded into circular discs and a complex cylindrical gyroid shape. A novel ink consisting of silver-coated carbon black nanoparticles in a thermoplastic polyurethane was used as the trace material. One version of the disc structural design has the advantage of allowing disassembly after testing for direct failure analysis. After increasing impacts, printed and traditionally potted circuits were examined for functionality. Additionally, in the open disc design, trace cracking and delamination of resistors were able to be observed. In a parallel study, we examined the shock mitigating behavior of 3D printed cellular gyroid structures on a Split Hopkinson Pressure Bar (SHPB). We explored alterations to the classic SHPB setup for testing the low impedance, cellular samples to most accurately reflect the stress state inside the sample (strain rates from 700 to 1750 s-1). We discovered that the gyroid can effectively absorb the impact of the test resulting in crushing the structure. Future studies aim to tailor the unit cell dimensions for certain frequencies, increase print accuracy and optimize material compositions for conductivity and adhesion to manufacture more durable devices.

Automated visual inspection system based on HAVNET architecture

NASA Astrophysics Data System (ADS)

Burkett, K.; Ozbayoglu, Murat A.; Dagli, Cihan H.

1994-10-01

In this study, the HAusdorff-Voronoi NETwork (HAVNET) developed at the UMR Smart Engineering Systems Lab is tested in the recognition of mounted circuit components commonly used in printed circuit board assembly systems. The automated visual inspection system used consists of a CCD camera, a neural network based image processing software and a data acquisition card connected to a PC. The experiments are run in the Smart Engineering Systems Lab in the Engineering Management Dept. of the University of Missouri-Rolla. The performance analysis shows that the vision system is capable of recognizing different components under uncontrolled lighting conditions without being effected by rotation or scale differences. The results obtained are promising and the system can be used in real manufacturing environments. Currently the system is being customized for a specific manufacturing application.

RGB-Stack Light Emitting Diode Modules with Transparent Glass Circuit Board and Oil Encapsulation

PubMed Central

Li, Ying-Chang; Chang, Yuan-Hsiao; Singh, Preetpal; Chang, Liann-Be; Yeh, Der-Hwa; Chao, Ting-Yu; Jian, Si-Yun; Li, Yu-Chi; Lai, Chao-Sung; Ying, Shang-Ping

2018-01-01

The light emitting diode (LED) is widely used in modern solid-state lighting applications, and its output efficiency is closely related to the submounts’ material properties. Most submounts used today, such as low-power printed circuit boards (PCBs) or high-power metal core printed circuit boards (MCPCBs), are not transparent and seriously decrease the output light extraction. To meet the requirements of high light output and better color mixing, a three-dimensional (3-D) stacked flip-chip (FC) LED module is proposed and demonstrated. To realize light penetration and mixing, the mentioned 3-D vertically stacking RGB LEDs use transparent glass as FC package submounts called glass circuit boards (GCB). Light emitted from each GCB stacked LEDs passes through each other and thus exhibits good output efficiency and homogeneous light-mixing characteristics. In this work, the parasitic problem of heat accumulation, which caused by the poor thermal conductivity of GCB and leads to a serious decrease in output efficiency, is solved by a proposed transparent cooling oil encapsulation (OCP) method. PMID:29494534

RGB-Stack Light Emitting Diode Modules with Transparent Glass Circuit Board and Oil Encapsulation.

PubMed

Li, Ying-Chang; Chang, Yuan-Hsiao; Singh, Preetpal; Chang, Liann-Be; Yeh, Der-Hwa; Chao, Ting-Yu; Jian, Si-Yun; Li, Yu-Chi; Tan, Cher Ming; Lai, Chao-Sung; Chow, Lee; Ying, Shang-Ping

2018-03-01

The light emitting diode (LED) is widely used in modern solid-state lighting applications, and its output efficiency is closely related to the submounts' material properties. Most submounts used today, such as low-power printed circuit boards (PCBs) or high-power metal core printed circuit boards (MCPCBs), are not transparent and seriously decrease the output light extraction. To meet the requirements of high light output and better color mixing, a three-dimensional (3-D) stacked flip-chip (FC) LED module is proposed and demonstrated. To realize light penetration and mixing, the mentioned 3-D vertically stacking RGB LEDs use transparent glass as FC package submounts called glass circuit boards (GCB). Light emitted from each GCB stacked LEDs passes through each other and thus exhibits good output efficiency and homogeneous light-mixing characteristics. In this work, the parasitic problem of heat accumulation, which caused by the poor thermal conductivity of GCB and leads to a serious decrease in output efficiency, is solved by a proposed transparent cooling oil encapsulation (OCP) method.

[Characterization of pyrolysis of waste printed circuit boards by high-resolution pyrolysis gas chromatography-mass spectrometry].

PubMed

Zhang, Yanhong; Huang, Hong; Xia, Zhengbin; Chen, Huanqin

2008-07-01

Thermal degradation of pyrolysis of waste circuit boards was investigated by high-resolution pyrolysis gas chromatography-mass spectrometry (PyGC-MS) and thermogravimetry (TG). In helium atmosphere, the products of FR-4 waste printed circuit board were pyrolyzed at 350, 450, 550, 650, and 750 degrees degrees C, separately, and the pyrolysis products were identified by online MS. The results indicated that the pyrolysis products of the FR-4 waste circuit board were three kinds of substances, such as the low boiling point products, phenol, bisphenol and their related products. Moreover, under 300 degrees degrees C, only observed less pyrolysis products. As the increase of pyrolysis temperature, the relative content of the low boiling point products increased. In the range of 450-650 degrees degrees C, the qualitative analysis and character were similar, and the relative contents of phenol and bisphenol were higher. The influence of pyrolysis temperature on pyrolyzate yields was studied. On the basis of the pyrolyzate profile and the dependence of pyrolyzate yields on pyrolysis temperature, the thermal degradation mechanism of brominated epoxy resin was proposed.

Integrated testing system FiTest for diagnosis of PCBA

NASA Astrophysics Data System (ADS)

Bogdan, Arkadiusz; Lesniak, Adam

2016-12-01

This article presents the innovative integrated testing system FiTest for automatic, quick inspection of printed circuit board assemblies (PCBA) manufactured in Surface Mount Technology (SMT). Integration of Automatic Optical Inspection (AOI), In-Circuit Tests (ICT) and Functional Circuit Tests (FCT) resulted in universal hardware platform for testing variety of electronic circuits. The platform provides increased test coverage, decreased level of false calls and optimization of test duration. The platform is equipped with powerful algorithms performing tests in a stable and repetitive way and providing effective management of diagnosis.

Future opportunities for advancing glucose test device electronics.

PubMed

Young, Brian R; Young, Teresa L; Joyce, Margaret K; Kennedy, Spencer I; Atashbar, Massood Z

2011-09-01

Advancements in the field of printed electronics can be applied to the field of diabetes testing. A brief history and some new developments in printed electronics components applicable to personal test devices, including circuitry, batteries, transmission devices, displays, and sensors, are presented. Low-cost, thin, and lightweight materials containing printed circuits with energy storage or harvest capability and reactive/display centers, made using new printing/imaging technologies, are ideal for incorporation into personal-use medical devices such as glucose test meters. Semicontinuous rotogravure printing, which utilizes flexible substrates and polymeric, metallic, and/or nano "ink" composite materials to effect rapidly produced, lower-cost printed electronics, is showing promise. Continuing research advancing substrate, "ink," and continuous processing development presents the opportunity for research collaboration with medical device designers. © 2011 Diabetes Technology Society.

An Undergraduate Design Experience in Digital Logic Design Course of Special Purpose Arithmetic Logic Unit Using Multisim, Ultiboard and Print Circuit Board

ERIC Educational Resources Information Center

Al-Haija, Qasem Abu; Al-Amri, Hasan; Al-Nashri, Mohamed; Al-Muhaisen, Sultan

2013-01-01

Project-Based Curriculum (PBC) is considered one of the most powerful methods in the engineering education where each course or courses-cluster is assigned a design project which considers a series of inter-related concepts that have been shown theoretically for the students. Using this approach, the student will gain the required knowledge in an…

Industrial Applications of Graphite Fluoride Fibers

NASA Technical Reports Server (NTRS)

Hung, Ching-Cheh; Kucera, Donald

1991-01-01

Based on fluorination technology developed during 1934 to 1959, and the fiber technology developed during the 1970s, a new process was developed to produce graphite fluoride fibers. In the process, pitch based graphitized carbon fibers are at first intercalated and deintercalated several times by bromine and iodine, followed by several cycles of nitrogen heating and fluorination at 350 to 370 C. Electrical, mechanical, and thermal properties of this fiber depend on the fluorination process and the fluorine content of the graphite fluoride product. However, these properties are between those of graphite and those of PTFE (Teflon). Therefore, it is considered to be a semiplastic. The physical properties suggest that this new material may have many new and unexplored applications. For example, it can be a thermally conductive electrical insulator. Its coefficient of thermal expansion (CTE) can be adjusted to match that of silicon, and therefore, it can be a heat sinking printed circuit board which is CTE compatible with silicon. Using these fibers in printed circuit boards may provide improved electrical performance and reliability of the electronics on the board over existing designs. Also, since it releases fluorine at 300 C or higher, it can be used as a material to store fluorine and to conduct fluorination. This application may simplify the fluorination process and reduce the risk of handling fluorine.

Separation of the metallic and non-metallic fraction from printed circuit boards employing green technology.

PubMed

Estrada-Ruiz, R H; Flores-Campos, R; Gámez-Altamirano, H A; Velarde-Sánchez, E J

2016-07-05

The generation of electrical and electronic waste is increasing day by day; recycling is attractive because of the metallic fraction containing these. Nevertheless, conventional techniques are highly polluting. The comminution of the printed circuit boards followed by an inverse flotation process is a clean technique that allows one to separate the metallic fraction from the non-metallic fraction. It was found that particle size and superficial air velocity are the main variables in the separation of the different fractions. In this way an efficient separation is achieved by avoiding the environmental contamination coupled with the possible utilization of the different fractions obtained. Copyright © 2016 Elsevier B.V. All rights reserved.

User's Guide for Computer Program that Routes Signal Traces

NASA Technical Reports Server (NTRS)

Hedgley, David R., Jr.

2000-01-01

This disk contains both a FORTRAN computer program and the corresponding user's guide that facilitates both its incorporation into your system and its utility. The computer program represents an efficient algorithm that routes signal traces on layers of a printed circuit with both through-pins and surface mounts. The computer program included is an implementation of the ideas presented in the theoretical paper titled "A Formal Algorithm for Routing Signal Traces on a Printed Circuit Board", NASA TP-3639 published in 1996. The computer program in the "connects" file can be read with a FORTRAN compiler and readily integrated into software unique to each particular environment where it might be used.

High-Resolution Graphene Films for Electrochemical Sensing via Inkjet Maskless Lithography.

PubMed

Hondred, John A; Stromberg, Loreen R; Mosher, Curtis L; Claussen, Jonathan C

2017-10-24

Solution-phase printing of nanomaterial-based graphene inks are rapidly gaining interest for fabrication of flexible electronics. However, scalable manufacturing techniques for high-resolution printed graphene circuits are still lacking. Here, we report a patterning technique [i.e., inkjet maskless lithography (IML)] to form high-resolution, flexible, graphene films (line widths down to 20 μm) that significantly exceed the current inkjet printing resolution of graphene (line widths ∼60 μm). IML uses an inkjet printed polymer lacquer as a sacrificial pattern, viscous spin-coated graphene, and a subsequent graphene lift-off to pattern films without the need for prefabricated stencils, templates, or cleanroom technology (e.g., photolithography). Laser annealing is employed to increase conductivity on thermally sensitive, flexible substrates [polyethylene terephthalate (PET)]. Laser annealing and subsequent platinum nanoparticle deposition substantially increases the electroactive nature of graphene as illustrated by electrochemical hydrogen peroxide (H 2 O 2 ) sensing [rapid response (5 s), broad linear sensing range (0.1-550 μm), high sensitivity (0.21 μM/μA), and low detection limit (0.21 μM)]. Moreover, high-resolution, complex graphene circuits [i.e., interdigitated electrodes (IDE) with varying finger width and spacing] were created with IML and characterized via potassium chloride (KCl) electrochemical impedance spectroscopy (EIS). Results indicated that sensitivity directly correlates to electrode feature size as the IDE with the smallest finger width and spacing (50 and 50 μm) displayed the largest response to changes in KCl concentration (∼21 kΩ). These results indicate that the developed IML patterning technique is well-suited for rapid, solution-phase graphene film prototyping on flexible substrates for numerous applications including electrochemical sensing.

Reusable vibration resistant integrated circuit mounting socket

DOEpatents

Evans, Craig N.

1995-01-01

This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and holds it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuit lead can be removed from the socket without damage either to the lead or to the socket components.

Nuclear code case development of printed-circuit heat exchangers with thermal and mechanical performance testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aakre, Shaun R.; Jentz, Ian W.; Anderson, Mark H.

The U.S. Department of Energy has agreed to fund a three-year integrated research project to close technical gaps involved with compact heat exchangers to be used in nuclear applications. This paper introduces the goals of the project, the research institutions, and industrial partners working in collaboration to develop a draft Boiler and Pressure Vessel Code Case for this technology. Heat exchanger testing, as well as non-destructive and destructive evaluation, will be performed by researchers across the country to understand the performance of compact heat exchangers. Testing will be performed using coolants and conditions proposed for Gen IV Reactor designs. Preliminarymore » observations of the mechanical failure mechanisms of the heat exchangers using destructive and non-destructive methods is presented. Unit-cell finite element models assembled to help predict the mechanical behavior of these high-temperature components are discussed as well. Performance testing methodology is laid out in this paper along with preliminary modeling results, an introduction to x-ray and neutron inspection techniques, and results from a recent pressurization test of a printed-circuit heat exchanger. The operational and quality assurance knowledge gained from these models and validation tests will be useful to developers of supercritical CO 2 systems, which commonly employ printed-circuit heat exchangers.« less

Removing lead from metallic mixture of waste printed circuit boards by vacuum distillation: factorial design and removal mechanism.

PubMed

Li, Xingang; Gao, Yujie; Ding, Hui

2013-10-01

The lead removal from the metallic mixture of waste printed circuit boards by vacuum distillation was optimized using experimental design, and a mathematical model was established to elucidate the removal mechanism. The variables studied in lead evaporation consisted of the chamber pressure, heating temperature, heating time, particle size and initial mass. The low-level chamber pressure was fixed at 0.1 Pa as the operation pressure. The application of two-level factorial design generated a first-order polynomial that agreed well with the data for evaporation efficiency of lead. The heating temperature and heating time exhibited significant effects on the efficiency, which was validated by means of the copper-lead mixture experiments. The optimized operating conditions within the region studied were the chamber pressure of 0.1 Pa, heating temperature of 1023 K and heating time of 120 min. After the conditions were employed to remove lead from the metallic mixture of waste printed circuit boards, the efficiency was 99.97%. The mechanism of the effects was elucidated by mathematical modeling that deals with evaporation, mass transfer and condensation, and can be applied to a wider range of metal removal by vacuum distillation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Low energy switching driver for printed electrochromic displays

NASA Astrophysics Data System (ADS)

Ionescu, Ciprian; Dobre, Robert Alexandru

2016-12-01

This paper continues our investigations in relatively new developed printed electrochromic displays (ECDs). There are some advantages of ECDs that recommend them for specific low end and short time disposable display applications, for instance the ECD devices present low power consumption (they are non-emissive, reflective, i.e. passive) and have a good viewing angle, looking like ink on paper. It is to note that these displays are still in research, and partly present on the market. There are a lot of papers regarding the chemistry and electro-chemistry of the device, but very few about concrete schematics for driving these displays. Due to their low penetration in applications, and due to lack of standardization, there are not yet realized custom drivers in form of integrated circuits. The driving of these circuits is not at all so simple. These are very sensitive devices in what it concerns exceeding the drive pulse duration and voltage level. In order to take full advantage of the low power consumption of this device, a good driver circuitry needs to be realized also in the "low power" class. We propose in this paper an original driving circuit, that has very low consumption and that can be even supplied by a supercapacitor or by a printed battery. The whole structure can be further integrated as a system on foil.

Solder Flux Residues and Humidity-Related Failures in Electronics: Relative Effects of Weak Organic Acids Used in No-Clean Flux Systems

NASA Astrophysics Data System (ADS)

Verdingovas, Vadimas; Jellesen, Morten Stendahl; Ambat, Rajan

2015-04-01

This paper presents the results of humidity testing of weak organic acids (WOAs), namely adipic, succinic, glutaric, dl-malic, and palmitic acids, which are commonly used as activators in no-clean solder fluxes. The study was performed under humidity conditions varying from 60% relative humidity (RH) to ˜99%RH at 25°C. The following parameters were used for characterization of WOAs: mass gain due to water adsorption and deliquescence of the WOA (by quartz crystal microbalance), resistivity of the water layer formed on the printed circuit board (by impedance spectroscopy), and leakage current measured using the surface insulation resistance pattern in the potential range from 0 V to 10 V. The combined results indicate the importance of the WOA chemical structure for the water adsorption and therefore conductive water layer formation on the printed circuit board assembly (PCBA). A substantial increase of leakage currents and probability of electrochemical migration was observed at humidity levels above the RH corresponding to the deliquescence point of WOAs present as contaminants on the printed circuit boards. The results suggest that use of solder fluxes with WOAs having higher deliquescence point could improve the reliability of electronics operating under circumstances in which exposure to high humidity is likely to occur.

Humidity Control in the U.S. Air Force Aircraft Service Shelter

DTIC Science & Technology

1988-06-30

printed circuit board control module , terminal boards, and blowt.r, etc.) are off-the-shelf commercial components. Only the humidifier ho:;Ift, I...indication of the shelter RH. - Circuit Breaker: A 20 amp, three pole breaker is providud fur equipment protection. o Water Storage Tank. A stainless...tapped into the shelter’s existing electrical system at the panelboard, on the load side of the 100 Amp main AC circuit breaker. Power is then

Optical printed circuit board (O-PCB) and VLSI photonic integrated circuits: visions, challenges, and progresses

NASA Astrophysics Data System (ADS)

Lee, El-Hang; Lee, S. G.; O, B. H.; Park, S. G.; Noh, H. S.; Kim, K. H.; Song, S. H.

2006-09-01

A collective overview and review is presented on the original work conducted on the theory, design, fabrication, and in-tegration of micro/nano-scale optical wires and photonic devices for applications in a newly-conceived photonic systems called "optical printed circuit board" (O-PCBs) and "VLSI photonic integrated circuits" (VLSI-PIC). These are aimed for compact, high-speed, multi-functional, intelligent, light-weight, low-energy and environmentally friendly, low-cost, and high-volume applications to complement or surpass the capabilities of electrical PCBs (E-PCBs) and/or VLSI electronic integrated circuit (VLSI-IC) systems. These consist of 2-dimensional or 3-dimensional planar arrays of micro/nano-optical wires and circuits to perform the functions of all-optical sensing, storing, transporting, processing, switching, routing and distributing optical signals on flat modular boards or substrates. The integrated optical devices include micro/nano-scale waveguides, lasers, detectors, switches, sensors, directional couplers, multi-mode interference devices, ring-resonators, photonic crystal devices, plasmonic devices, and quantum devices, made of polymer, silicon and other semiconductor materials. For VLSI photonic integration, photonic crystals and plasmonic structures have been used. Scientific and technological issues concerning the processes of miniaturization, interconnection and integration of these systems as applicable to board-to-board, chip-to-chip, and intra-chip integration, are discussed along with applications for future computers, telecommunications, and sensor-systems. Visions and challenges toward these goals are also discussed.

Passive UHF RFID Tag for Multispectral Assessment

PubMed Central

Escobedo, Pablo; Carvajal, Miguel A.; Capitán-Vallvey, Luis F.; Fernández-Salmerón, José; Martínez-Olmos, Antonio; Palma, Alberto J.

2016-01-01

This work presents the design, fabrication, and characterization of a passive printed radiofrequency identification tag in the ultra-high-frequency band with multiple optical sensing capabilities. This tag includes five photodiodes to cover a wide spectral range from near-infrared to visible and ultraviolet spectral regions. The tag antenna and circuit connections have been screen-printed on a flexible polymeric substrate. An ultra-low-power microcontroller-based switch has been included to measure the five magnitudes issuing from the optical sensors, providing a spectral fingerprint of the incident electromagnetic radiation from ultraviolet to infrared, without requiring energy from a battery. The normalization procedure has been designed applying illuminants, and the entire system was tested by measuring cards from a colour chart and sensing fruit ripening. PMID:27428973

Passive UHF RFID Tag for Multispectral Assessment.

PubMed

Escobedo, Pablo; Carvajal, Miguel A; Capitán-Vallvey, Luis F; Fernández-Salmerón, José; Martínez-Olmos, Antonio; Palma, Alberto J

2016-07-14

This work presents the design, fabrication, and characterization of a passive printed radiofrequency identification tag in the ultra-high-frequency band with multiple optical sensing capabilities. This tag includes five photodiodes to cover a wide spectral range from near-infrared to visible and ultraviolet spectral regions. The tag antenna and circuit connections have been screen-printed on a flexible polymeric substrate. An ultra-low-power microcontroller-based switch has been included to measure the five magnitudes issuing from the optical sensors, providing a spectral fingerprint of the incident electromagnetic radiation from ultraviolet to infrared, without requiring energy from a battery. The normalization procedure has been designed applying illuminants, and the entire system was tested by measuring cards from a colour chart and sensing fruit ripening.

Helping the Visually Impaired Student with Electronic Video Visual Aids.

ERIC Educational Resources Information Center

Visualtek, Inc., Santa Monica, CA.

THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: Video visual aids are Closed Circuit TV systems (CCTV's) which magnify print and enlarge it electronically upon a screen so partially sighted persons with some residual vision can read and write normal size print. These devices are in use around the world in homes, schools, industries and libraries,…

Flip-flop logic circuit based on fully solution-processed organic thin film transistor devices with reduced variations in electrical performance

NASA Astrophysics Data System (ADS)

Takeda, Yasunori; Yoshimura, Yudai; Adib, Faiz Adi Ezarudin Bin; Kumaki, Daisuke; Fukuda, Kenjiro; Tokito, Shizuo

2015-04-01

Organic reset-set (RS) flip-flop logic circuits based on pseudo-CMOS inverters have been fabricated using full solution processing at a relatively low process temperatures of 150 °C or less. The work function for printed silver electrodes was increased from 4.7 to 5.4 eV through surface modification with a self-assembled monolayer (SAM) material. A bottom-gate, bottom-contact organic thin-film transistor (OTFT) device using a solution-processable small-molecular semiconductor material exhibited field-effect mobility of 0.40 cm2 V-1 s-1 in the saturation region and a threshold voltage (VTH) of -2.4 V in ambient air operation conditions. In order to reduce the variations in mobility and VTH, we designed a circuit with six transistors arranged in parallel, in order to average out their electrical characteristics. As a result, we have succeeded in reducing these variations without changing the absolute values of the mobility and VTH. The fabricated RS flip-flop circuits were functioned well and exhibited short delay times of 3.5 ms at a supply voltage of 20 V.

Circuit-lead trimming template

NASA Technical Reports Server (NTRS)

Ofarrell, K.; Winn, E.

1979-01-01

Template for use in trimming leads on production wiring boards is low-cost means for eliminating rejections for short leads and improving lead-strength uniformity. Template is simply unclad piece of printed-circuit board material that is drilled using same drill control tape used in making original production board. Revisions in component layout of board can therefore be made simultaneously in template.

Surface study of graphene ink for fine solid lines printed on BOPP Substrate in micro-flexographic printing using XPS analysis technique

NASA Astrophysics Data System (ADS)

Hassan, S.; Yusof, M. S.; Embong, Z.; Ding, S.; Maksud, M. I.

2018-01-01

Micro-flexographic printing is a combination of flexography and micro-contact printing technique. It is a new printing method for fine solid lines printing purpose. Graphene material has been used as depositing agent or printing ink in other printing technique like inkjet printing. This graphene ink is printed on biaxially oriented polypropylene (BOPP) by using Micro-flexographic printing technique. The choose of graphene as a printing ink is due to its wide application in producing electronic and micro-electronic devices such as Radio-frequency identification (RFID) and printed circuit board. The graphene printed on the surface of BOPP substrate was analyzed using X-Ray Photoelectron Spectroscopy (XPS). The positions for each synthetic component in the narrow scan are referred to the electron binding energy (eV). This research is focused on two narrow scan regions which are C 1s and O 1s. Further discussion of the narrow scan spectrum will be explained in detail. From the narrow scan analysis, it is proposed that from the surface adhesive properties of graphene, it is suitable as an alternative printing ink medium for Micro-flexographic printing technique in printing multiple fine solid lines at micro to nano scale feature.

Separation and Recovery of Fine Particles from Waste Circuit Boards Using an Inflatable Tapered Diameter Separation Bed

PubMed Central

Sheng, Cheng; Wu, Lingling; Zhao, Yuemin; He, Jinfeng; Zhou, Enhui

2014-01-01

Recovering particle materials from discarded printed circuit boards can enhance resource recycling and reduce environmental pollution. Efficiently physically separating and recovering fine metal particles (−0.5 mm) from the circuit boards are a key recycling challenge. To do this, a new type of separator, an inflatable tapered diameter separation bed, was developed to study particle motion and separation mechanisms in the bed's fluid flow field. For 0.5–0.25 mm circuit board particles, metal recovery rates ranged from 87.56 to 94.17%, and separation efficiencies ranged from 87.71 to 94.20%. For 0.25–0.125 mm particles, metal recovery rates ranged from 84.76 to 91.97%, and separation efficiencies ranged from 84.74 to 91.86%. For superfine products (−0.125 mm), metal recovery rates ranged from 73.11 to 83.04%, and separation efficiencies ranged from 73.00 to 83.14%. This research showed that the inflatable tapered diameter separation bed achieved efficient particle separation and can be used to recover fine particles under a wide range of operational conditions. The bed offers a new mechanical technology to recycle valuable materials from discarded printed circuit boards, reducing environmental pollution. PMID:25379546

Electronic Jewelry

ERIC Educational Resources Information Center

Ward, Vesta

1972-01-01

Brightly banded resisters, condensers, diodes and transistors as well as printed circuit boards were used with the objective of discovering their potential in creating objects for personal adornment. (RB)

3D printed Lego®-like modular microfluidic devices based on capillary driving.

PubMed

Nie, Jing; Gao, Qing; Qiu, Jing-Jiang; Sun, Miao; Liu, An; Shao, Lei; Fu, Jian-Zhong; Zhao, Peng; He, Yong

2018-03-12

The field of how to rapidly assemble microfluidics with modular components continuously attracts researchers' attention, however, extra efforts must be devoted to solving the problems of leaking and aligning between individual modules. This paper presents a novel type of modular microfluidic device, driven by capillary force. There is no necessity for a strict seal or special alignment, and its open structures make it easy to integrate various stents and reactants. The key rationale for this method is to print different functional modules with a low-cost three-dimensional (3D) printer, then fill the channels with capillary materials and assemble them with plugs like Lego ® bricks. This rapidly reconstructed modular microfluidic device consists of a variety of common functional modules and other personalized modules, each module having a unified standard interface for easy assembly. As it can be printed by a desktop 3D printer, the manufacturing process is simple and efficient, with controllable regulation of the flow channel scale. Through diverse combinations of different modules, a variety of different functions can be achieved, without duplicating the manufacturing process. A single module can also be taken out for testing and analysis. What's more, combined with basic circuit components, it can serve as a low-cost Lego ® -like modular microfluidic circuits. As a proof of concept, the modular microfluidic device has been successfully demonstrated and used for stent degradation and cell cultures, revealing the potential use of this method in both chemical and biological research.

Development of high-resolution two-dimensional magnetic field measurement system by use of printed-circuit technology

NASA Astrophysics Data System (ADS)

Akimitsu, Moe; Qinghong, Cao; Sawada, Asuka; Hatano, Hironori; Tanabe, Hiroshi; Ono, Yasushi; TS-Group Team

2017-10-01

We have developed a new-types of high-resolution magnetic probe array for our new magnetic reconnection experiments: TS-3U (ST, FRC: R =0.2m, 2017-) and TS-4U (ST, FRC: R =0.5m, 2018-), using the advanced printed-circuit technology. They are equipped with all three-components of magnetic pick-up coils whose size is 1-5mm x 3mm. Each coil is composed of two-sided coil pattern with line width of 0.05mm. We can install two or three printed arrays in a single glass (ceramic) tube for two or three component measurements. Based on this new probe technique, we started high-resolution and high-accuracy measurement of the current sheet thickness and studied its plasma parameter dependence. We found that the thickness of current sheet increases inversely with the guide toroidal field. It is probably determined by the ion gyroradius in agreement with the particle simulation by Horiuchi etc. While the reconnection speed is steady under low guide field condition, it is observed to oscillate in the specific range of guide field, suggesting transition from the quasi-steady reconnection to the intermittent reconnection. Cause and mechanism for intermittent reconnection will be discussed using the current sheet dissipation and dynamic balance between plasma inflow and outflow. This work supported by JSPS KAKENHI Grant Numbers 15H05750, 15K14279 and 17H04863.

An Exploratory Study of the Effect of Screen Size and Resolution on the Legibility of Graphics in Automated Job Performance Aids. Final Report.

ERIC Educational Resources Information Center

Dwyer, Daniel J.

Designed to assess the effect of alternative display (CRT) screen sizes and resolution levels on user ability to identify and locate printed circuit (PC) board points, this study is the first in a protracted research program on the legibility of graphics in computer-based job aids. Air Force maintenance training pipeline students (35 male and 1…

A Printed Organic Amplification System for Wearable Potentiometric Electrochemical Sensors.

PubMed

Shiwaku, Rei; Matsui, Hiroyuki; Nagamine, Kuniaki; Uematsu, Mayu; Mano, Taisei; Maruyama, Yuki; Nomura, Ayako; Tsuchiya, Kazuhiko; Hayasaka, Kazuma; Takeda, Yasunori; Fukuda, Takashi; Kumaki, Daisuke; Tokito, Shizuo

2018-03-02

Electrochemical sensor systems with integrated amplifier circuits play an important role in measuring physiological signals via in situ human perspiration analysis. Signal processing circuitry based on organic thin-film transistors (OTFTs) have significant potential in realizing wearable sensor devices due to their superior mechanical flexibility and biocompatibility. Here, we demonstrate a novel potentiometric electrochemical sensing system comprised of a potassium ion (K + ) sensor and amplifier circuits employing OTFT-based pseudo-CMOS inverters, which have a highly controllable switching voltage and closed-loop gain. The ion concentration sensitivity of the fabricated K + sensor was 34 mV/dec, which was amplified to 160 mV/dec (by a factor of 4.6) with high linearity. The developed system is expected to help further the realization of ultra-thin and flexible wearable sensor devices for healthcare applications.

Basic research for development of the beam profile monitor based on a Faraday cup array system

NASA Astrophysics Data System (ADS)

Park, Mook-Kwang

2015-10-01

The basic design used to develop a beam profile monitor based on a Faraday cup array (FCA), which has the advantages of high robustness, reliability, and long-term stability, along with the ability to measure the ion current over a wide dynamic range, was developed. The total system is divided into three parts: i.e., a faraday cup, measuring electronics, and a display program part. The FCA was considered to consist of a collimator, suppressor, insulator frame, and 64 (8 × 8 array) tiny Faraday cups (FC). An electronic circuit using a multiplexer was applied to effectively address many signal lines and the printed circuit board (PCB) was designed to be divided into three parts, i.e., an electrode PCB (ELEC PCB), capacitance PCB (CAP PCB), and control PCB (CON PCB).

Laser printing of 3D metallic interconnects

NASA Astrophysics Data System (ADS)

Beniam, Iyoel; Mathews, Scott A.; Charipar, Nicholas A.; Auyeung, Raymond C. Y.; Piqué, Alberto

2016-04-01

The use of laser-induced forward transfer (LIFT) techniques for the printing of functional materials has been demonstrated for numerous applications. The printing gives rise to patterns, which can be used to fabricate planar interconnects. More recently, various groups have demonstrated electrical interconnects from laser-printed 3D structures. The laser printing of these interconnects takes place through aggregation of voxels of either molten metal or of pastes containing dispersed metallic particles. However, the generated 3D structures do not posses the same metallic conductivity as a bulk metal interconnect of the same cross-section and length as those formed by wire bonding or tab welding. An alternative is to laser transfer entire 3D structures using a technique known as lase-and-place. Lase-and-place is a LIFT process whereby whole components and parts can be transferred from a donor substrate onto a desired location with one single laser pulse. This paper will describe the use of LIFT to laser print freestanding, solid metal foils or beams precisely over the contact pads of discrete devices to interconnect them into fully functional circuits. Furthermore, this paper will also show how the same laser can be used to bend or fold the bulk metal foils prior to transfer, thus forming compliant 3D structures able to provide strain relief for the circuits under flexing or during motion from thermal mismatch. These interconnect "ridges" can span wide gaps (on the order of a millimeter) and accommodate height differences of tens of microns between adjacent devices. Examples of these laser printed 3D metallic bridges and their role in the development of next generation electronics by additive manufacturing will be presented.

Description of the three axis low-g accelerometer package

NASA Technical Reports Server (NTRS)

Amalavage, A. J.; Fikes, E. H.; Berry, E. H.

1978-01-01

The three axis low-g accelerometer package designed for use on the Space Processing Application Rocket (SPAR) Program is described. The package consists of the following major sections: (1) three Kearfott model 2412 accelerometers mounted in an orthogonal triad configuration on a temperature controlled, thermally isolated cube, (2) the accelerometer servoelectronics (printed circuit cards PC-6 through PC-12), and (3) the signal conditioner (printed circuit cards PC-15 and PC-16). The measurement range is 0 + or - 0.031 g with a quantization of 1.1 x 10 to the 7th power g. The package was flown successfully on six SPAR launches with the Black Brant booster. These flights provide approximately 300 s of free fall or zero-g environment.

Carbon black dispersion pre-plating technology for printed wire board manufacturing. Final technology evaluation report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Folsom, D.W.; Gavaskar, A.R.; Jones, J.A.

1993-10-01

The project compared chemical use, waste generation, cost, and product quality between electroless copper and carbon-black-based preplating technologies at the printed wire board (PWB) manufacturing facility of McCurdy Circuits in Orange, CA. The carbon-black based preplating technology evaluated is used as an alternative process for electroless copper (EC) plating of through-holes before electrolytic copper plating. The specific process used at McCurdy is the BlackHole (BH) technology process, which uses a dispersion of carbon black in an aqueous solution to provide a conductive surface for subsequent electrolytic copper plating. The carbon-black dispersion technology provided effective waste reduction and long-term cost savings.more » The economic analysis determined that the new process was cost efficient because chemical use was reduced and the process proved more efficient; the payback period was less than 4 yrs.« less

Solution-printed organic semiconductor blends exhibiting transport properties on par with single crystals

PubMed Central

Niazi, Muhammad R.; Li, Ruipeng; Qiang Li, Er; Kirmani, Ahmad R.; Abdelsamie, Maged; Wang, Qingxiao; Pan, Wenyang; Payne, Marcia M.; Anthony, John E.; Smilgies, Detlef-M.; Thoroddsen, Sigurdur T.; Giannelis, Emmanuel P.; Amassian, Aram

2015-01-01

Solution-printed organic semiconductors have emerged in recent years as promising contenders for roll-to-roll manufacturing of electronic and optoelectronic circuits. The stringent performance requirements for organic thin-film transistors (OTFTs) in terms of carrier mobility, switching speed, turn-on voltage and uniformity over large areas require performance currently achieved by organic single-crystal devices, but these suffer from scale-up challenges. Here we present a new method based on blade coating of a blend of conjugated small molecules and amorphous insulating polymers to produce OTFTs with consistently excellent performance characteristics (carrier mobility as high as 6.7 cm2 V−1 s−1, low threshold voltages of<1 V and low subthreshold swings <0.5 V dec−1). Our findings demonstrate that careful control over phase separation and crystallization can yield solution-printed polycrystalline organic semiconductor films with transport properties and other figures of merit on par with their single-crystal counterparts. PMID:26592862

Solution-printed organic semiconductor blends exhibiting transport properties on par with single crystals.

PubMed

Niazi, Muhammad R; Li, Ruipeng; Qiang Li, Er; Kirmani, Ahmad R; Abdelsamie, Maged; Wang, Qingxiao; Pan, Wenyang; Payne, Marcia M; Anthony, John E; Smilgies, Detlef-M; Thoroddsen, Sigurdur T; Giannelis, Emmanuel P; Amassian, Aram

2015-11-23

Solution-printed organic semiconductors have emerged in recent years as promising contenders for roll-to-roll manufacturing of electronic and optoelectronic circuits. The stringent performance requirements for organic thin-film transistors (OTFTs) in terms of carrier mobility, switching speed, turn-on voltage and uniformity over large areas require performance currently achieved by organic single-crystal devices, but these suffer from scale-up challenges. Here we present a new method based on blade coating of a blend of conjugated small molecules and amorphous insulating polymers to produce OTFTs with consistently excellent performance characteristics (carrier mobility as high as 6.7 cm(2) V(-1) s(-1), low threshold voltages of<1 V and low subthreshold swings <0.5 V dec(-1)). Our findings demonstrate that careful control over phase separation and crystallization can yield solution-printed polycrystalline organic semiconductor films with transport properties and other figures of merit on par with their single-crystal counterparts.

A novel 3D bioprinted flexible and biocompatible hydrogel bioelectronic platform.

PubMed

Agarwala, Shweta; Lee, Jia Min; Ng, Wei Long; Layani, Michael; Yeong, Wai Yee; Magdassi, Shlomo

2018-04-15

Bioelectronics platforms are gaining widespread attention as they provide a template to study the interactions between biological species and electronics. Decoding the effect of the electrical signals on the cells and tissues holds the promise for treating the malignant tissue growth, regenerating organs and engineering new-age medical devices. This work is a step forward in this direction, where bio- and electronic materials co-exist on one platform without any need for post processing. We fabricate a freestanding and flexible hydrogel based platform using 3D bioprinting. The fabrication process is simple, easy and provides a flexible route to print materials with preferred shapes, size and spatial orientation. Through the design of interdigitated electrodes and heating coil, the platform can be tailored to print various circuits for different functionalities. The biocompatibility of the printed platform is tested using C2C12 murine myoblasts cell line. Furthermore, normal human dermal fibroblasts (primary cells) are also seeded on the platform to ascertain the compatibility. Copyright © 2017 Elsevier B.V. All rights reserved.

A Comprehensive Surface Mount Technology Solution for Integrated Circuits onto Flexible Screen Printed Electrical Interconnects

DTIC Science & Technology

2014-05-19

their acceptable thermal stability, Polyimides have established as a conventional substrate material for flexible interconnects, which can be...of the silver flake ink for the screen-printed interconnects, the assembled unit fulfills biocompatibility requirements in a limited manner ([29...30]). Even though biocompatibility of substrate [31] is fulfilled, toxicity of the insulating mask [32] and encapsulation need to be considered

Electro-optical backplane demonstrator with integrated multimode gradient-index thin glass waveguide panel

NASA Astrophysics Data System (ADS)

Schröder, Henning; Brusberg, Lars; Pitwon, Richard; Whalley, Simon; Wang, Kai; Miller, Allen; Herbst, Christian; Weber, Daniel; Lang, Klaus-Dieter

2015-03-01

Optical interconnects for data transmission at board level offer increased energy efficiency, system density, and bandwidth scalability compared to purely copper driven systems. We present recent results on manufacturing of electrooptical printed circuit board (PCB) with integrated planar glass waveguides. The graded index multi-mode waveguides are patterned inside commercially available thin-glass panels by performing a specific ion-exchange process. The glass waveguide panel is embedded within the layer stack-up of a PCB using proven industrial processes. This paper describes the design, manufacture, assembly and characterization of the first electro-optical backplane demonstrator based on integrated planar glass waveguides. The electro-optical backplane in question is created by laminating the glass waveguide panel into a conventional multi-layer electronic printed circuit board stack-up. High precision ferrule mounts are automatically assembled, which will enable MT compliant connectors to be plugged accurately to the embedded waveguide interfaces on the glass panel edges. The demonstration platform comprises a standardized sub-rack chassis and five pluggable test cards each housing optical engines and pluggable optical connectors. The test cards support a variety of different data interfaces and can support data rates of up to 32 Gb/s per channel.

Integrated printed circuit board device for cell lysis and nucleic acid extraction.

PubMed

Marshall, Lewis A; Wu, Liang Li; Babikian, Sarkis; Bachman, Mark; Santiago, Juan G

2012-11-06

Preparation of raw, untreated biological samples remains a major challenge in microfluidics. We present a novel microfluidic device based on the integration of printed circuit boards and an isotachophoresis assay for sample preparation of nucleic acids from biological samples. The device has integrated resistive heaters and temperature sensors as well as a 70 μm × 300 μm × 3.7 cm microfluidic channel connecting two 15 μL reservoirs. We demonstrated this device by extracting pathogenic nucleic acids from 1 μL dispensed volume of whole blood spiked with Plasmodium falciparum. We dispensed whole blood directly onto an on-chip reservoir, and the system's integrated heaters simultaneously lysed and mixed the sample. We used isotachophoresis to extract the nucleic acids into a secondary buffer via isotachophoresis. We analyzed the convective mixing action with micro particle image velocimetry (micro-PIV) and verified the purity and amount of extracted nucleic acids using off-chip quantitative polymerase chain reaction (PCR). We achieved a clinically relevant limit of detection of 500 parasites per microliter. The system has no moving parts, and the process is potentially compatible with a wide range of on-chip hybridization or amplification assays.

Delamination mechanism study of large size waste printed circuit boards by using dimethylacetamide.

PubMed

Verma, Himanshu Ranjan; Singh, Kamalesh K; Mankhand, Tilak Raj

2017-07-01

Present work investigates the recycling of waste printed circuit boards (PCBs) by cracking of its multi-layered structure by using dimethylacetamide (DMA). The study shows that cracking and separation of layers of PCBs increases as the temperature increases; and decreases as the surface area of PCBs increases. After separation of layers, the used solvent was analyzed by proton and carbon nuclear magnetic resonance spectroscopy (NMR) to understand the dissolution phenomenon of resin. Further, NMR and Fourier transform infrared spectroscopy analysis of DMA sample after 1h, 2h, 3h, 4h and 8h of reaction with PCBs at 433K and PCB:DMA ratio (wt/vol) of 3:10 has been carried out to investigate the mechanism of dissolution of resin. These studies revealed that hydroxyl group of PCBs polymeric chain participates in hydrogen bonding with parent carbonyl group of DMA molecule that results in the solvation of resin. Possible chemical reaction based on the above finding has been discussed. Using this technique, separation of the metallic fraction without application of any energy intensive mechanical pre-processing is possible. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Novel Designed Bioreactor for Recovering Precious Metals from Waste Printed Circuit Boards

PubMed Central

Jujun, Ruan; Jie, Zheng; Jian, Hu; Zhang, Jianwen

2015-01-01

For recovering precious metals from waste printed circuit boards (PCBs), a novel hybrid technology including physical and biological methods was developed. It consisted of crushing, corona-electrostatic separation, and bioleaching. Bioleaching process is the focus of this paper. A novel bioreactor for bioleaching was designed. Bioleaching was carried out using Pseudomonas chlororaphis. Bioleaching experiments using mixed particles of Au and Cu were performed and leachate contained 0.006 mg/L, 2823 mg/L Au+ and Cu2+ respectively. It showed when Cu existed, the concentrations of Au were extremely small. This provided the feasibility to separate Cu from Au. The method of orthogonal experimental design was employed in the simulation bioleaching experiments. Experimental results showed the optimized parameters for separating Cu from Au particles were pH 7.0, temperature 22.5 °C, and rotation speed 80 r/min. Based on the optimized parameters obtained, the bioreactor was operated for recovering mixed Au and Cu particles. 88.1 wt.% of Cu and 76.6 wt.% of Au were recovered. The paper contributed important information to recover precious metals from waste PCBs. PMID:26316021

Design for low-power and reliable flexible electronics

NASA Astrophysics Data System (ADS)

Huang, Tsung-Ching (Jim)

Flexible electronics are emerging as an alternative to conventional Si electronics for large-area low-cost applications such as e-paper, smart sensors, and disposable RFID tags. By utilizing inexpensive manufacturing methods such as ink-jet printing and roll-to-roll imprinting, flexible electronics can be made on low-cost plastics just like printing a newspaper. However, the key elements of exible electronics, thin-film transistors (TFTs), have slower operating speeds and less reliability than their Si electronics counterparts. Furthermore, depending on the material property, TFTs are usually mono-type -- either p- or n-type -- devices. Making air-stable complementary TFT circuits is very challenging and not applicable to most TFT technologies. Existing design methodologies for Si electronics, therefore, cannot be directly applied to exible electronics. Other inhibiting factors such as high supply voltage, large process variation, and lack of trustworthy device modeling also make designing larger-scale and robust TFT circuits a significant challenge. The major goal of this dissertation is to provide a viable solution for robust circuit design in exible electronics. I will first introduce a reliability simulation framework that can predict the degraded TFT circuits' performance under bias-stress. This framework has been validated using the amorphous-silicon (a-Si) TFT scan driver for TFT-LCD displays. To reuse the existing CMOS design ow for exible electronics, I propose a Pseudo-CMOS cell library that can make TFT circuits operable under low supply voltage and which has post-fabrication tunability for reliability and performance enhancement. This cell library has been validated using 2V self-assembly-monolayer (SAM) organic TFTs with a low-cost shadow-mask deposition process. I will also demonstrate a 3-bit 1.25KS/s Flash ADC in a-Si TFTs, which is based on the proposed Pseudo-CMOS cell library, and explore more possibilities in display, energy, and sensing applications.

Extremely high frequency RF effects on electronics.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale

The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit boardmore » traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.« less

Generating millimeter-wave Bessel beam with orbital angular momentum using reflective-type metasurface inherently integrated with source

NASA Astrophysics Data System (ADS)

Shen, Yizhu; Yang, Jiawei; Meng, Hongfu; Dou, Wenbin; Hu, Sanming

2018-04-01

Metasurfaces, orbital angular momenta (OAM), and non-diffractive Bessel beams have been attracting worldwide research. Combining the benefits of these three promising techniques, this paper proposes a metasurface-based reflective-type approach to generate a first-order Bessel beam carrying OAM. To validate this approach, a millimeter-wave metasurface is analyzed, designed, fabricated, and measured. Experimental results agree well with simulation. Moreover, this reflective-type metasurface, generating a Bessel beam with OAM, is inherently integrated with a planar feeding source in the same single-layer printed circuit board. Therefore, the proposed design features low profile, low cost, easy integration with front-end active circuits, and no alignment error between the feeding source and the metasurface.

A Tactile Sensor Network System Using a Multiple Sensor Platform with a Dedicated CMOS-LSI for Robot Applications †

PubMed Central

Shao, Chenzhong; Tanaka, Shuji; Nakayama, Takahiro; Hata, Yoshiyuki; Bartley, Travis; Muroyama, Masanori

2017-01-01

Robot tactile sensation can enhance human–robot communication in terms of safety, reliability and accuracy. The final goal of our project is to widely cover a robot body with a large number of tactile sensors, which has significant advantages such as accurate object recognition, high sensitivity and high redundancy. In this study, we developed a multi-sensor system with dedicated Complementary Metal-Oxide-Semiconductor (CMOS) Large-Scale Integration (LSI) circuit chips (referred to as “sensor platform LSI”) as a framework of a serial bus-based tactile sensor network system. The sensor platform LSI supports three types of sensors: an on-chip temperature sensor, off-chip capacitive and resistive tactile sensors, and communicates with a relay node via a bus line. The multi-sensor system was first constructed on a printed circuit board to evaluate basic functions of the sensor platform LSI, such as capacitance-to-digital and resistance-to-digital conversion. Then, two kinds of external sensors, nine sensors in total, were connected to two sensor platform LSIs, and temperature, capacitive and resistive sensing data were acquired simultaneously. Moreover, we fabricated flexible printed circuit cables to demonstrate the multi-sensor system with 15 sensor platform LSIs operating simultaneously, which showed a more realistic implementation in robots. In conclusion, the multi-sensor system with up to 15 sensor platform LSIs on a bus line supporting temperature, capacitive and resistive sensing was successfully demonstrated. PMID:29061954

A Tactile Sensor Network System Using a Multiple Sensor Platform with a Dedicated CMOS-LSI for Robot Applications.

PubMed

Shao, Chenzhong; Tanaka, Shuji; Nakayama, Takahiro; Hata, Yoshiyuki; Bartley, Travis; Nonomura, Yutaka; Muroyama, Masanori

2017-08-28

Robot tactile sensation can enhance human-robot communication in terms of safety, reliability and accuracy. The final goal of our project is to widely cover a robot body with a large number of tactile sensors, which has significant advantages such as accurate object recognition, high sensitivity and high redundancy. In this study, we developed a multi-sensor system with dedicated Complementary Metal-Oxide-Semiconductor (CMOS) Large-Scale Integration (LSI) circuit chips (referred to as "sensor platform LSI") as a framework of a serial bus-based tactile sensor network system. The sensor platform LSI supports three types of sensors: an on-chip temperature sensor, off-chip capacitive and resistive tactile sensors, and communicates with a relay node via a bus line. The multi-sensor system was first constructed on a printed circuit board to evaluate basic functions of the sensor platform LSI, such as capacitance-to-digital and resistance-to-digital conversion. Then, two kinds of external sensors, nine sensors in total, were connected to two sensor platform LSIs, and temperature, capacitive and resistive sensing data were acquired simultaneously. Moreover, we fabricated flexible printed circuit cables to demonstrate the multi-sensor system with 15 sensor platform LSIs operating simultaneously, which showed a more realistic implementation in robots. In conclusion, the multi-sensor system with up to 15 sensor platform LSIs on a bus line supporting temperature, capacitive and resistive sensing was successfully demonstrated.

Evaluating print performance of Sn-Ag-Cu lead-free solder pastes used in electronics assembly process

NASA Astrophysics Data System (ADS)

Mallik, S.; Bauer, R.; Hübner, F.; Ekere, N. N.

2011-01-01

Solder paste is the most widely used interconnection material in the electronic assembly process for attaching electronic components/devices directly onto the surface of printed circuit boards, using stencil printing process. This paper evaluates the performance of three different commercially available Sn-Ag-Cu solder pastes formulated with different particle size distributions (PSD), metal content and alloy composition. A series of stencil printing tests were carried out using a specially designed stencil of 75 μm thickness and apertures of 300×300 μm2 dimension and 500 μm pitch sizes. Solder paste printing behaviors were found related to attributes such as slumping and surface tension and printing performance was correlated with metal content and PSD. The results of the study should benefit paste manufacturers and SMT assemblers to improve their products and practices.

A Microcomputer-Based Program for Printing Check Plots of Integrated Circuits Specified in Caltech Intermediate Form.

DTIC Science & Technology

1984-12-01

only four transistors[5]. Each year since that time, the semiconductor industry has con- sistently improved the quality of the fabrication tech- niques...rarely took place at universities and was almost exclusively confined to industry . IC design techniques were developed, tested, and taught only in the...community, it is not uncommon for industry to borrow ideas and even particular programs from these university designed tools. The Very Large Scale Integration

A Parallel Neuromorphic Text Recognition System and Its Implementation on a Heterogeneous High-Performance Computing Cluster

DTIC Science & Technology

2013-01-01

M. Ahmadi, and M. Shridhar, “ Handwritten Numeral Recognition with Multiple Features and Multistage Classifiers,” Proc. IEEE Int’l Symp. Circuits...ARTICLE (Post Print) 3. DATES COVERED (From - To) SEP 2011 – SEP 2013 4. TITLE AND SUBTITLE A PARALLEL NEUROMORPHIC TEXT RECOGNITION SYSTEM AND ITS...research in computational intelligence has entered a new era. In this paper, we present an HPC-based context-aware intelligent text recognition

Recycle technology for recovering resources and products from waste printed circuit boards.

PubMed

Li, Jia; Lu, Hongzhou; Guo, Jie; Xu, Zhenming; Zhou, Yaohe

2007-03-15

The printed circuit board (PCB) contains nearly 28% metals that are abundant non-ferrous metals such as Cu, Al, Sn, etc. The purity of precious metals in PCBs is more than 10 times higher than that of rich-content minerals. Therefore, recycling of PCBs is an important subject not only from the treatment of waste but also from the recovery of valuable materials. Chemical and mechanical methods are two traditional recycling processes for waste PCBs. However, the prospect of chemical methods will be limited since the emission of toxic liquid or gas brings secondary pollution to the environment during the process. Mechanical processes, such as shape separation, jigging, density-based separation, and electrostatic separation have been widely utilized in the recycling industry. But, recycling of waste PCBs is only beginning. In this study, a total of 400 kg of waste PCBs was processed by a recycle technology without negative impact to the environment. The technology contained mechanical two-step crushing, corona electrostatic separating, and recovery. The results indicated that (i) two-step crushing was an effect process to strip metals from base plates completely; (ii) the size of particles between 0.6 and 1.2 mm was suitable for corona electrostatic separating during industrial application; and (iii) the nonmetal of waste PCBs attained 80% weight of a kind of nonmetallic plate that expanded the applying prospect of waste nonmetallic materials.

Direct-referencing Two-dimensional-array Digital Microfluidics Using Multi-layer Printed Circuit Board

PubMed Central

Gong, Jian; Kim, Chang-Jin “CJ”

2008-01-01

Digital (i.e. droplet-based) microfluidics, by the electrowetting-on-dielectric (EWOD) mechanism, has shown great potential for a wide range of applications, such as lab-on-a-chip. While most reported EWOD chips use a series of electrode pads essentially in one-dimensional line pattern designed for specific tasks, the desired universal chips allowing user-reconfigurable paths would require the electrode pads in two-dimensional pattern. However, to electrically access the electrode pads independently, conductive lines need to be fabricated underneath the pads in multiple layers, raising a cost issue especially for disposable chip applications. In this article, we report the building of digital microfluidic plates based on a printed-circuit-board (PCB), in which multilayer electrical access lines were created inexpensively using mature PCB technology. However, due to its surface topography and roughness and resulting high resistance against droplet movement, as-fabricated PCB surfaces require unacceptably high (~500 V) voltages unless coated with or immersed in oil. Our goal is EWOD operations of aqueous droplets not only on oil-covered but also on dry surfaces. To meet varying levels of performances, three types of gradually complex post-PCB microfabrication processes are developed and evaluated. By introducing land-grid-array (LGA) sockets in the packaging, a scalable digital microfluidics system with reconfigurable and low-cost chip is also demonstrated. PMID:19234613

Inexpensive Implementation of Many Strain Gauges

NASA Technical Reports Server (NTRS)

Berkun, Andrew C.

2010-01-01

It has been proposed to develop arrays of strain gauges as arrays of ordinary metal film resistors and associated electronic readout circuitry on printed circuit boards or other suitable substrates. This proposal is a by-product of a development of instrumentation utilizing metal film resistors on printed-circuit boards to measure temperatures at multiple locations. In the course of that development, it was observed that in addition to being sensitive to temperature, the metal film resistors were also sensitive to strains in the printed-circuit boards to which they were attached. Because of the low cost of ordinary metal film resistors (typically <$0.01 apiece at 2007 prices), the proposal could enable inexpensive implementation of arrays of many (e.g., 100 or more) strain gauges, possibly concentrated in small areas. For example, such an array could be designed for use as a computer keyboard with no moving parts, as a device for sensing the shape of an object resting on a surface, or as a device for measuring strains at many points on a mirror, a fuel tank, an airplane wing, or other large object. Ordinarily, the effect of strain on resistance would be regarded as a nuisance in a temperature-measuring application, and the effect of temperature on resistance would be regarded as a nuisance in a strain-measuring application. The strain-induced changes in resistance of the metal film resistors in question are less than those of films in traditional strain gauges. The main novel aspect of present proposal lies in the use of circuitry affording sufficient sensitivity to measure strain plus means for compensating for the effect of temperature. For an array of metal film resistors used as proposed, the readout circuits would include a high-accuracy analog-to-digital converter fed by a low noise current source, amplifier chain, and an analog multiplexer chain. Corrections would be provided by use of high-accuracy calibration resistors and a temperature sensor. By use of such readout circuitry, it would be possible to read the resistances of as many as 100 fixed resistors in a time interval of 1 second at a resolution much greater than 16 bits. The readout data would be processed, along with temperature calibration data, to deduce the strain on the printed-circuit board or other substrate in the areas around the resistors. It should also be possible to also deduce the temperature from the readings.

Tape transfer printing of a liquid metal alloy for stretchable RF electronics.

PubMed

Jeong, Seung Hee; Hjort, Klas; Wu, Zhigang

2014-09-03

In order to make conductors with large cross sections for low impedance radio frequency (RF) electronics, while still retaining high stretchability, liquid-alloy-based microfluidic stretchable electronics offers stretchable electronic systems the unique opportunity to combine various sensors on our bodies or organs with high-quality wireless communication with the external world (devices/systems), without sacrificing enhanced user comfort. This microfluidic approach, based on printed circuit board technology, allows large area processing of large cross section conductors and robust contacts, which can handle a lot of stretching between the embedded rigid active components and the surrounding system. Although it provides such benefits, further development is needed to realize its potential as a high throughput, cost-effective process technology. In this paper, tape transfer printing is proposed to supply a rapid prototyping batch process at low cost, albeit at a low resolution of 150 μm. In particular, isolated patterns can be obtained in a simple one-step process. Finally, a stretchable radio frequency identification (RFID) tag is demonstrated. The measured results show the robustness of the hybrid integrated system when the tag is stretched at 50% for 3000 cycles.

Wideband analytical equivalent circuit for one-dimensional periodic stacked arrays.

PubMed

Molero, Carlos; Rodríguez-Berral, Raúl; Mesa, Francisco; Medina, Francisco; Yakovlev, Alexander B

2016-01-01

A wideband equivalent circuit is proposed for the accurate analysis of scattering from a set of stacked slit gratings illuminated by a plane wave with transverse magnetic or electric polarization that impinges normally or obliquely along one of the principal planes of the structure. The slit gratings are printed on dielectric slabs of arbitrary thickness, including the case of closely spaced gratings that interact by higher-order modes. A Π-circuit topology is obtained for a pair of coupled arrays, with fully analytical expressions for all the circuit elements. This equivalent Π circuit is employed as the basis to derive the equivalent circuit of finite stacks with any given number of gratings. Analytical expressions for the Brillouin diagram and the Bloch impedance are also obtained for infinite periodic stacks.

Active alignment/contact verification system

DOEpatents

Greenbaum, William M.

2000-01-01

A system involving an active (i.e. electrical) technique for the verification of: 1) close tolerance mechanical alignment between two component, and 2) electrical contact between mating through an elastomeric interface. For example, the two components may be an alumina carrier and a printed circuit board, two mating parts that are extremely small, high density parts and require alignment within a fraction of a mil, as well as a specified interface point of engagement between the parts. The system comprises pairs of conductive structures defined in the surfaces layers of the alumina carrier and the printed circuit board, for example. The first pair of conductive structures relate to item (1) above and permit alignment verification between mating parts. The second pair of conductive structures relate to item (2) above and permit verification of electrical contact between mating parts.

Method of defining features on materials with a femtosecond laser

DOEpatents

Roos, Edward Victor [Los Altos, CA; Roeske, Franklin [Livermore, CA; Lee, Ronald S [Livermore, CA; Benterou, Jerry J [Livermore, CA

2006-05-23

The invention relates to a pulsed laser ablation method of metals and/or dielectric films from the surface of a wafer, printed circuit board or a hybrid substrate. By utilizing a high-energy ultra-short pulses of laser light, such a method can be used to manufacture electronic circuits and/or electro-mechanical assemblies without affecting the material adjacent to the ablation zone.

A digital receiver module with direct data acquisition for magnetic resonance imaging systems.

PubMed

Tang, Weinan; Sun, Hongyu; Wang, Weimin

2012-10-01

A digital receiver module for magnetic resonance imaging (MRI) with detailed hardware implementations is presented. The module is based on a direct sampling scheme using the latest mixed-signal circuit design techniques. A single field-programmable gate array chip is employed to perform software-based digital down conversion for radio frequency signals. The modular architecture of the receiver allows multiple acquisition channels to be implemented on a highly integrated printed circuit board. To maintain the phase coherence of the receiver and the exciter in the context of direct sampling, an effective phase synchronization method was proposed to achieve a phase deviation as small as 0.09°. The performance of the described receiver module was verified in the experiments for both low- and high-field (0.5 T and 1.5 T) MRI scanners and was compared to a modern commercial MRI receiver system.

Packaging Technologies for 500 C SiC Electronics and Sensors: Challenges in Material Science and Technology

NASA Technical Reports Server (NTRS)

Chen, Liang-Yu; Neudeck, Philip G.; Behelm, Glenn M.; Spry, David J.; Meredith, Roger D.; Hunter, Gary W.

2015-01-01

This paper presents ceramic substrates and thick-film metallization based packaging technologies in development for 500C silicon carbide (SiC) electronics and sensors. Prototype high temperature ceramic chip-level packages and printed circuit boards (PCBs) based on ceramic substrates of aluminum oxide (Al2O3) and aluminum nitride (AlN) have been designed and fabricated. These ceramic substrate-based chip-level packages with gold (Au) thick-film metallization have been electrically characterized at temperatures up to 550C. The 96 alumina packaging system composed of chip-level packages and PCBs has been successfully tested with high temperature SiC discrete transistor devices at 500C for over 10,000 hours. In addition to tests in a laboratory environment, a SiC junction field-effect-transistor (JFET) with a packaging system composed of a 96 alumina chip-level package and an alumina printed circuit board was tested on low earth orbit for eighteen months via a NASA International Space Station experiment. In addition to packaging systems for electronics, a spark-plug type sensor package based on this high temperature interconnection system for high temperature SiC capacitive pressure sensors was also developed and tested. In order to further significantly improve the performance of packaging system for higher packaging density, higher operation frequency, power rating, and even higher temperatures, some fundamental material challenges must be addressed. This presentation will discuss previous development and some of the challenges in material science (technology) to improve high temperature dielectrics for packaging applications.

Elements configuration of the open lead test circuit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fukuzaki, Yumi, E-mail: 14514@sr.kagawa-nct.ac.jp; Ono, Akira

In the field of electronics, small electronic devices are widely utilized because they are easy to carry. The devices have various functions by user’s request. Therefore, the lead’s pitch or the ball’s pitch have been narrowed and high-density printed circuit board has been used in the devices. Use of the ICs which have narrow lead pitch makes normal connection difficult. When logic circuits in the devices are fabricated with the state-of-the-art technology, some faults have occurred more frequently. It can be divided into types of open faults and short faults. We have proposed a new test method using a testmore » circuit in the past. This paper propose elements configuration of the test circuit.« less

Reusable vibration resistant integrated circuit mounting socket

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evans, C.N.

1993-12-31

This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and hold it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuitmore » lead can be removed from the socket without damage either to the lead or to the socket components.« less

Reusable vibration resistant integrated circuit mounting socket

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evans, C.N.

1995-08-29

This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and holds it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuitmore » lead can be removed from the socket without damage either to the lead or to the socket components. 11 figs.« less

Design and Fabrication of an Experimental Microheater Array Powder Sintering Printer

NASA Astrophysics Data System (ADS)

Holt, Nicholas; Zhou, Wenchao

2018-03-01

Microheater array powder sintering (MAPS) is a novel additive manufacturing process that uses an array of microheaters to selectively sinter powder particles. MAPS shows great promise as a new method of printing flexible electronics by enabling digital curing of conductive inks on a variety of substrates. For MAPS to work effectively, a microscale air gap needs to be maintained between the heater array and the conductive ink. In this article, we present an experimental MAPS printer with air gap control for printing conductive circuits. First, we discuss design aspects necessary to implement MAPS. An analysis is performed to validate that the design can maintain the desired air gap between the microheaters and the sintering layer, which consists of a silver nanoparticle ink. The printer is tested by printing conductive lines on a flexible plastic substrate with silver nanoparticle ink. Results show MAPS performs on par with or better than the existing fabrication methods for printed electronics in terms of both the print quality (conductivity of the printed line) and print speed, which shows MAPS' great promise as a competitive new method for digital production of printed electronics.

GRC-2013-C-02448

NASA Image and Video Library

2009-06-23

Environmental Portrait, Electrical Power Systems Employee, hardware for the High Power 300-Volt Power Processing Unit (PPU). The Printed Circuit Boards (PCBs) are the Discharge Module Inverter and the Pulse Width Modulation (PWM) Controller

New polymeric materials for designing photoresistors and photodetective assemblies based on CdHgTe

NASA Astrophysics Data System (ADS)

Khitrova, L. M.; Troshkin, Y. S.; Belyaev, V. P.; Popovyan, G. E.; Kiseleva, L. V.

1999-06-01

In order to improve quality of photodetectors and photodetective assemblies two new cryo- and chemically resistant adhesives were developed: epoxy-silico-organic adhesive `(Phi) X-5P' and acrylic `OPHOH-2' adhesive for gluing of CdHgTe wafers to a substrate `XCK-H' vacuum-tight modified adhesive is used for attaching of inlet windows and glass holder elements. `OPUOH-65' vibration damping thixotropic composition was developed for mounting of multi- layer printed circuits.

Advanced Polymers for Practical Use

NASA Technical Reports Server (NTRS)

1999-01-01

Resulting from a SBIR contract with the Goddard Space Flight Center, Foster-Miller developed a high performance, low cost substrate for printed circuits with a coefficient of thermal expansion (CTE) matched to the surface mounted devices. The commercial product that resulted from the agreement between the two organizations was so successful that Foster-Miller created a spin-off company named Superex, Inc., devoted solely to the promotion of this particular substrate. The contract originated from NASA's need to develop better, more cost effective satellite and land based electronic applications.

An interactive wire-wrap board layout program

NASA Technical Reports Server (NTRS)

Schlutsmeyer, A.

1987-01-01

An interactive computer-graphics-based tool for specifying the placement of electronic parts on a wire-wrap circuit board is presented. Input is a data file (currently produced by a commercial logic design system) which describes the parts used and their interconnections. Output includes printed reports describing the parts and wire paths, parts counts, placement lists, board drawing, and a tape to send to the wire-wrap vendor. The program should reduce the engineer's layout time by a factor of 3 to 5 as compared to manual methods.

Silicon photonic IC embedded optical-PCB for high-speed interconnect application

NASA Astrophysics Data System (ADS)

Kallega, Rakshitha; Nambiar, Siddharth; Kumar, Abhai; Ranganath, Praveen; Selvaraja, Shankar Kumar

2018-02-01

Optical-Printed Circuit Board (PCB) is an emerging optical interconnect technology to bridge the gap between the board edge and the processing module. The technology so far has been used as a broadband transmitter using polymer waveguides in the PCB. In this paper, we report a Silicon Nitride based photonic IC embedded in the PCB along with the polymers as waveguides in the PCB. The motivation for such integration is to bring routing capability and to reduce the power loss due to broadcasting mode.

A Q-band low noise GaAs pHEMT MMIC power amplifier for pulse electron spin resonance spectrometer

NASA Astrophysics Data System (ADS)

Sitnikov, A.; Kalabukhova, E.; Oliynyk, V.; Kolisnichenko, M.

2017-05-01

We present the design and development of a single stage pulse power amplifier working in the frequency range 32-38 GHz based on a monolithic microwave integrated circuit (MMIC). We have designed the MMIC power amplifier by using the commercially available packaged GaAs pseudomorphic high electron mobility transistor. The circuit fabrication and assembly process includes the elaboration of the matching networks for the MMIC power amplifier and their assembling as well as the topology outline and fabrication of the printed circuit board of the waveguide-microstrip line transitions. At room ambient temperature, the measured peak output power from the prototype amplifier is 35.5 dBm for 16.6 dBm input driving power, corresponding to 19 dB gain. The measured rise/fall time of the output microwave signal modulated by a high-speed PIN diode was obtained as 5-6 ns at 20-250 ns pulse width with 100 kHz pulse repetition rate frequency.

A Q-band low noise GaAs pHEMT MMIC power amplifier for pulse electron spin resonance spectrometer.

PubMed

Sitnikov, A; Kalabukhova, E; Oliynyk, V; Kolisnichenko, M

2017-05-01

We present the design and development of a single stage pulse power amplifier working in the frequency range 32-38 GHz based on a monolithic microwave integrated circuit (MMIC). We have designed the MMIC power amplifier by using the commercially available packaged GaAs pseudomorphic high electron mobility transistor. The circuit fabrication and assembly process includes the elaboration of the matching networks for the MMIC power amplifier and their assembling as well as the topology outline and fabrication of the printed circuit board of the waveguide-microstrip line transitions. At room ambient temperature, the measured peak output power from the prototype amplifier is 35.5 dBm for 16.6 dBm input driving power, corresponding to 19 dB gain. The measured rise/fall time of the output microwave signal modulated by a high-speed PIN diode was obtained as 5-6 ns at 20-250 ns pulse width with 100 kHz pulse repetition rate frequency.

Resistence seam welding thin copper foils

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hollar, D.L. Jr.

1991-02-01

Use of flat flexible circuits in the electronics industry is expanding. The term flexible circuits'' is defined here as copper foil which has been bonded to an insulating film such as Kapton film. The foil is photo processed to produce individual circuit paths similar to printed circuit boards. Another insulating film is laminated over the conductors to complete the flexible circuit. Flexible circuits, like multiwire cables, are susceptible to electromagnetic radiation (EMR) interference. On multiwire cables the interference problem is mitigated by adding a woven wire braid shielding over the conductors. Shielding on flexible circuits is accomplished by enclosing themore » circuits in a copper foil envelope. However, the copper foil must be electrically sealed around the flexcircuit to be effective. Ultimately, a resistance seam welding process and appropriate equipment were developed which would provide the required electrical seal between two layers of 2-oz (0.0028-inch thick) copper foil on a 1.1-inch wide, 30-inch long, 0.040-inch thick flexible circuit. 4 refs., 19 figs.« less

Characterizing Graphene-modified Electrodes for Interfacing with Arduino®-based Devices.

PubMed

Arris, Farrah Aida; Ithnin, Mohamad Hafiz; Salim, Wan Wardatul Amani Wan

2016-08-01

Portable low-cost platform and sensing systems for identification and quantitative measurement are in high demand for various environmental monitoring applications, especially in field work. Quantifying parameters in the field requires both minimal sample handling and a device capable of performing measurements with high sensitivity and stability. Furthermore, the one-device-fits-all concept is useful for continuous monitoring of multiple parameters. Miniaturization of devices can be achieved by introducing graphene as part of the transducer in an electrochemical sensor. In this project, we characterize graphene deposition methods on glassy-carbon electrodes (GCEs) with the goal of interfacing with an Arduino-based user-friendly microcontroller. We found that a galvanostatic electrochemical method yields the highest peak current of 10 mA, promising a highly sensitive electrochemical sensor. An Atlas Scientific™ printed circuit board (PCB) was connected to an Arduino® microcontroller using a multi-circuit connection that can be interfaced with graphene-based electrochemical sensors for environmental monitoring.

Analysis of Multilayered Printed Circuit Boards using Computed Tomography

DTIC Science & Technology

2014-05-01

complex PCBs that present a challenge for any testing or fault analysis. Set-to- work testing and fault analysis of any electronic circuit require...Electronic Warfare and Radar Division in December 2010. He is currently in Electro- Optic Countermeasures Group. Samuel works on embedded system design...and software optimisation of complex electro-optical systems, including the set to work and characterisation of these systems. He has a Bachelor of

Microfluidics with fluid walls.

PubMed

Walsh, Edmond J; Feuerborn, Alexander; Wheeler, James H R; Tan, Ann Na; Durham, William M; Foster, Kevin R; Cook, Peter R

2017-10-10

Microfluidics has great potential, but the complexity of fabricating and operating devices has limited its use. Here we describe a method - Freestyle Fluidics - that overcomes many key limitations. In this method, liquids are confined by fluid (not solid) walls. Aqueous circuits with any 2D shape are printed in seconds on plastic or glass Petri dishes; then, interfacial forces pin liquids to substrates, and overlaying an immiscible liquid prevents evaporation. Confining fluid walls are pliant and resilient; they self-heal when liquids are pipetted through them. We drive flow through a wide range of circuits passively by manipulating surface tension and hydrostatic pressure, and actively using external pumps. Finally, we validate the technology with two challenging applications - triggering an inflammatory response in human cells and chemotaxis in bacterial biofilms. This approach provides a powerful and versatile alternative to traditional microfluidics.The complexity of fabricating and operating microfluidic devices limits their use. Walsh et al. describe a method in which circuits are printed as quickly and simply as writing with a pen, and liquids in them are confined by fluid instead of solid walls.

Electrochemical Migration Behavior of Copper-Clad Laminate and Electroless Nickel/Immersion Gold Printed Circuit Boards under Thin Electrolyte Layers

PubMed Central

Yi, Pan; Xiao, Kui; Ding, Kangkang; Dong, Chaofang; Li, Xiaogang

2017-01-01

The electrochemical migration (ECM) behavior of copper-clad laminate (PCB-Cu) and electroless nickel/immersion gold printed circuit boards (PCB-ENIG) under thin electrolyte layers of different thicknesses containing 0.1 M Na2SO4 was studied. Results showed that, under the bias voltage of 12 V, the reverse migration of ions occurred. For PCB-Cu, both copper dendrites and sulfate precipitates were found on the surface of FR-4 (board material) between two plates. Moreover, the Cu dendrite was produced between the two plates and migrated toward cathode. Compared to PCB-Cu, PCB-ENIG exhibited a higher tendency of ECM failure and suffered from seriously short circuit failure under high relative humidity (RH) environment. SKP results demonstrated that surface potentials of the anode plates were greater than those of the cathode plates, and those potentials of the two plates exhibited a descending trend as the RH increased. At the end of the paper, an electrochemical migration corrosion failure model of PCB was proposed. PMID:28772497

Programmable logic devices

NASA Astrophysics Data System (ADS)

Jacobs, J. L.

1993-04-01

Erasable programmable logic devices (EPLD's) were investigated to determine their advantages and/or disadvantages in Test Equipment Engineering applications. It was found that EPLD's performed as well as or better than identical circuits using standard transistor transistor logic (TTL). The chip count in these circuits was reduced, saving printed circuit board space and shortening fabrication and prove-in time. Troubleshooting circuits of EPLD's was also easier with 10 to 100 times fewer wires needed. The reduced number of integrated circuits (IC's) contributed to faster system speeds and an overall lower power consumption. In some cases changes to the circuit became software changes using EPLD's instead of hardware changes for standard logic. Using EPLD's was fairly easy; however, as with any new technology, a learning curve must be overcome before EPLD's can be used efficiently. The many benefits of EPLD's outweighed this initial inconvenience.

High-Throughput Printing Process for Flexible Electronics

NASA Astrophysics Data System (ADS)

Hyun, Woo Jin

Printed electronics is an emerging field for manufacturing electronic devices with low cost and minimal material waste for a variety of applications including displays, distributed sensing, smart packaging, and energy management. Moreover, its compatibility with roll-to-roll production formats and flexible substrates is desirable for continuous, high-throughput production of flexible electronics. Despite the promise, however, the roll-to-roll production of printed electronics is quite challenging due to web movement hindering accurate ink registration and high-fidelity printing. In this talk, I will present a promising strategy for roll-to-roll production using a novel printing process that we term SCALE (Self-aligned Capillarity-Assisted Lithography for Electronics). By utilizing capillarity of liquid inks on nano/micro-structured substrates, the SCALE process facilitates high-resolution and self-aligned patterning of electrically functional inks with greatly improved printing tolerance. I will show the fabrication of key building blocks (e.g. transistor, resistor, capacitor) for electronic circuits using the SCALE process on plastics.

Electrical and electronic devices and components: A compilation

NASA Technical Reports Server (NTRS)

1975-01-01

Components and techniques which may be useful in the electronics industry are described. Topics discussed include transducer technology, printed-circuit technology, solid state devices, MOS transistors, Gunn device, microwave antennas, and position indicators.

Ergonomics improvements of the visual inspection process in a printed circuit assembly factory.

PubMed

Yeow, Paul H P; Sen, Rabindra Nath

2004-01-01

An ergonomics improvement study was conducted on the visual inspection process of a printed circuit assembly (PCA) factory. The process was studied through subjective assessment and direct observation. Three problems were identified: operators' eye problems, insufficient time for inspection and ineffective visual inspection. These problems caused a huge yearly rejection cost of US 298,240 dollars, poor quality, customer dissatisfaction and poor occupational health and safety. Ergonomics interventions were made to rectify the problems: reduced usage of a magnifying glass, the use of less glaring inspection templates, inspection of only electrically non-tested components and introduction of a visual inspection sequence. The interventions produced savings in rejection cost, reduced operators' eye strain, headaches and watery eyes, lowered the defect percentage at customers' sites and increased the factory's productivity and customer satisfaction.

A new strain for recovering precious metals from waste printed circuit boards.

PubMed

Ruan, Jujun; Zhu, Xingjiong; Qian, Yiming; Hu, Jian

2014-05-01

A new strain, Pseudomonas Chlororaphis (PC), was found for dissolving gold, silver, and copper from the metallic particles of crushed waste printed circuit boards (PCBs). The optimized conditions that greatly improved the ability of producing CN- (for dissolving metals) were obtained. Dissolving experiments of pure gold, silver, and copper showed that the metals could be changed into Au+, Ag+, and Cu2+. PC cells and their secreta would adsorb metallic ions. Meanwhile, metallic ions destroyed the growth of PC. Dissolving experiments of metallic particles from crushed waste PCBs were performed by PC. The results indicated that 8.2% of the gold, 12.1% silver, and 52.3% copper were dissolved into solution. This paper contributed significance information to recovering precious metals from waste PCBs by bioleaching. Copyright © 2014 Elsevier Ltd. All rights reserved.

PCBA depaneling stress minimization study

NASA Astrophysics Data System (ADS)

Darus, M. H. B. M.; Aziz, M. H. B. A.; Ong, N. R.; Alcain, J. B.; Retnasamy, V.

2017-09-01

Printed circuit board (PCB) is board that used to connect the electricity using the conductive pathways. The PCB that consists with electronic components was called as printed circuit board assembly (PCBA). Bending process has been used as one of the depaneling techniques may contribute to mechanical stress and the failure of capacitors and other components to function. As a result, the idea to create holes in particular location was implemented in order to absorb the stress. In this study, finite element analysis is demonstrated by using ANSYS software. Two PCBA design models are considered in order to investigate the effect of the hole and the stress response. The simulation results show that the hole on the PCBA has reduced the stress. For Design model 2, the stress response of the holes located vertically to the PCBA is lower than the holes located horizontally to the PCBA.

Volumetric segmentation of range images for printed circuit board inspection

NASA Astrophysics Data System (ADS)

Van Dop, Erik R.; Regtien, Paul P. L.

1996-10-01

Conventional computer vision approaches towards object recognition and pose estimation employ 2D grey-value or color imaging. As a consequence these images contain information about projections of a 3D scene only. The subsequent image processing will then be difficult, because the object coordinates are represented with just image coordinates. Only complicated low-level vision modules like depth from stereo or depth from shading can recover some of the surface geometry of the scene. Recent advances in fast range imaging have however paved the way towards 3D computer vision, since range data of the scene can now be obtained with sufficient accuracy and speed for object recognition and pose estimation purposes. This article proposes the coded-light range-imaging method together with superquadric segmentation to approach this task. Superquadric segments are volumetric primitives that describe global object properties with 5 parameters, which provide the main features for object recognition. Besides, the principle axes of a superquadric segment determine the phase of an object in the scene. The volumetric segmentation of a range image can be used to detect missing, false or badly placed components on assembled printed circuit boards. Furthermore, this approach will be useful to recognize and extract valuable or toxic electronic components on printed circuit boards scrap that currently burden the environment during electronic waste processing. Results on synthetic range images with errors constructed according to a verified noise model illustrate the capabilities of this approach.

Wirelessly powered microfluidic dielectrophoresis devices using printable RF circuits.

PubMed

Qiao, Wen; Cho, Gyoujin; Lo, Yu-Hwa

2011-03-21

We report the first microfluidic device integrated with a printed RF circuit so the device can be wirelessly powered by a commercially available RFID reader. For conventional dielectrophoresis devices, electrical wires are needed to connect the electric components on the microchip to external equipment such as power supplies, amplifiers, function generators, etc. Such a procedure is unfamiliar to most clinicians and pathologists who are used to working with a microscope for examination of samples on microscope slides. The wirelessly powered device reported here eliminates the entire need for wire attachments and external instruments so the operators can use the device in essentially the same manner as they do with microscope slides. The integrated circuit can be fabricated on a flexible plastic substrate at very low cost using a roll-to-roll printing method. Electrical power at 13.56 MHz transmitted by a radio-frequency identification (RFID) reader is inductively coupled to the printed RFIC and converted into 10 V DC (direct current) output, which provides sufficient power to drive a microfluidic device to manipulate biological particles such as beads and proteins via the DC dielectrophoresis (DC-DEP) effect. To our best knowledge, this is the first wirelessly powered microfluidic dielectrophoresis device. Although the work is preliminary, the device concept, the architecture, and the core technology are expected to stimulate many efforts in the future and transform the technology to a wide range of clinical and point-of-care applications. This journal is © The Royal Society of Chemistry 2011

Selective separation of copper over solder alloy from waste printed circuit boards leach solution.

PubMed

Kavousi, Maryam; Sattari, Anahita; Alamdari, Eskandar Keshavarz; Firozi, Sadegh

2017-02-01

The printed circuit boards (PCBs) from electronic waste are important resource, since the PCBs contain precious metals such as gold, copper, tin, silver, platinum and so forth. In addition to the economic point of view, the presence of lead turns this scrap into dangerous to environment. This study was conducted as part of the development of a novel process for selective recovery of copper over tin and lead from printed circuit boards by HBF 4 leaching. In previous study, Copper with solder alloy was associated, simultaneously were leached in HBF 4 solution using hydrogen peroxide as an oxidant at room temperature. The objective of this study is the separation of copper from tin and lead from Fluoroborate media using CP-150 as an extractant. The influence of organic solvent's concentration, pH, temperature and A/O phase ratio was investigated. The possible extraction mechanism and the composition of the extracted species have been determined. The separation factors for these metals using this agent are reported, while efficient methods for separation of Cu (II) from other metal ions are proposed. The treatment of leach liquor for solvent extraction of copper with CP-150 revealed that 20% CP-150 in kerosene, a 30min period of contact time, and a pH of 3 were sufficient for the extraction of Cu(II) and 99.99% copper was recovered from the leached solution. Copyright © 2016. Published by Elsevier Ltd.

Hydrothermal modification and recycling of nonmetallic particles from waste print circuit boards.

PubMed

Gao, Xuehua; Li, Qisheng; Qiu, Jun

2018-04-01

Nonmetallic particles recycled from waste print circuit boards (NPRPs) were modified by a hydrothermal treatment method and the catalysts, solvents, temperature and time were investigated, which affected the modification effect of NPRPs. The mild hydrothermal treatment method does not need high temperature, and would not cause secondary pollution. Further, the modified NPRPs were used as the raw materials for the epoxy resin and glass fibers/epoxy resin composites, which were prepared by pouring and hot-pressing method. The mechanical properties and morphology of the composites were discussed. The results showed that relative intensity of the hydroxyl bonds on the surface of NPRPs increased 58.9% after modification. The mechanical tests revealed that both flexural and impact properties of the composites can be significantly improved by adding the modified NPRPs. Particularly, the maximum increment of flexural strength, flexural modulus and impact strength of the epoxy matrix composites with 30% modified NPRPs is 40.1%, 80.0% and 79.0%, respectively. Hydrothermal treatment can modify surface of NPRPs successfully and modified NPRPs can not only improve the properties of the composites, but also reduce the production cost of the composites and environmental pollution. Thus, we develop a new way to recycle nonmetallic materials of waste print circuit boards and the highest level of waste material recycling with the raw materials-products-raw materials closed cycle can be realized through the hydrothermal modification and reuse of NPRPs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Recent advances in photonics packaging materials

NASA Astrophysics Data System (ADS)

Zweben, Carl

2006-02-01

There are now over a dozen low-CTE materials with thermal conductivities between that of copper (400 w/m-K) and over 4X copper (1700 W/m-K). Most have low densities. For comparison, traditional low-CTE packaging materials like copper/tungsten have thermal conductivities that are little or no better than that of aluminum (200 W/m-K) and high densities. There are also low-density thermal insulators with low CTEs. Some advanced materials are low cost. Most do not outgas. They have a wide range of electrical properties that can be used to minimize electromagnetic emissions or provide EMI shielding. Several are now in commercial and aerospace applications, including laser diode packages; light-emitting diode (LED) packages; thermoelectric cooler bases, plasma displays; power modules; servers; laptops; heat sinks; thermally conductive, low-CTE printed circuit boards; and printed circuit board cold plates. Advanced material payoffs include: improved thermal performance, reliability, alignment and manufacturing yield; reduced thermal stresses and heating power requirements; simplified thermal design; enablement of hard solder direct attach; weight savings up to 85%; size reductions up to 65%; and lower cost. This paper discusses the large and increasing number of advanced packaging materials, including properties, development status, applications, increasing manufacturing yield, cost, lessons learned and future directions, including nanocomposites.

Status of electronic waste recycling techniques: a review.

PubMed

Abdelbasir, Sabah M; Hassan, Saad S M; Kamel, Ayman H; El-Nasr, Rania Seif

2018-05-08

The increasing use of electrical and electronic equipment leads to a huge generation of electronic waste (e-waste). It is the fastest growing waste stream in the world. Almost all electrical and electronic equipment contain printed circuit boards as an essential part. Improper handling of these electronic wastes could bring serious risk to human health and the environment. On the other hand, proper handling of this waste requires a sound management strategy for awareness, collection, recycling, and reuse. Nowadays, the effective recycling of this type of waste has been considered as a main challenge for any society. Printed circuit boards (PCBs), which are the base of many electronic industries, are rich in valuable heavy metals and toxic halogenated organic substances. In this review, the composition of different PCBs and their harmful effects are discussed. Various techniques in common use for recycling the most important metals from the metallic fractions of e-waste are illustrated. The recovery of metals from e-waste material after physical separation through pyrometallurgical, hydrometallurgical, or biohydrometallurgical routes is also discussed, along with alternative uses of non-metallic fraction. The data are explained and compared with the current e-waste management efforts done in Egypt. Future perspectives and challenges facing Egypt for proper e-waste recycling are also discussed.

A Combination of Boron Nitride Nanotubes and Cellulose Nanofibers for the Preparation of a Nanocomposite with High Thermal Conductivity.

PubMed

Zeng, Xiaoliang; Sun, Jiajia; Yao, Yimin; Sun, Rong; Xu, Jian-Bin; Wong, Ching-Ping

2017-05-23

With the current development of modern electronics toward miniaturization, high-degree integration and multifunctionalization, considerable heat is accumulated, which results in the thermal failure or even explosion of modern electronics. The thermal conductivity of materials has thus attracted much attention in modern electronics. Although polymer composites with enhanced thermal conductivity are expected to address this issue, achieving higher thermal conductivity (above 10 W m -1 K -1 ) at filler loadings below 50.0 wt % remains challenging. Here, we report a nanocomposite consisting of boron nitride nanotubes and cellulose nanofibers that exhibits high thermal conductivity (21.39 W m -1 K -1 ) at 25.0 wt % boron nitride nanotubes. Such high thermal conductivity is attributed to the high intrinsic thermal conductivity of boron nitride nanotubes and cellulose nanofibers, the one-dimensional structure of boron nitride nanotubes, and the reduced interfacial thermal resistance due to the strong interaction between the boron nitride nanotubes and cellulose nanofibers. Using the as-prepared nanocomposite as a flexible printed circuit board, we demonstrate its potential usefulness in electronic device-cooling applications. This thermally conductive nanocomposite has promising applications in thermal interface materials, printed circuit boards or organic substrates in electronics and could supplement conventional polymer-based materials.

Phase-lock-loop application for fiber optic receiver

NASA Astrophysics Data System (ADS)

Ruggles, Stephen L.; Wills, Robert W.

1991-02-01

Phase-locked loop circuits are frequently employed in communication systems. In recent years, digital phase-locked loop circuits were utilized in optical communications systems. In an optical transceiver system, the digital phase-locked loop circuit is connected to the output of the receiver to extract a clock signal from the received coded data (NRZ, Bi-Phase, or Manchester). The clock signal is then used to reconstruct or recover the original data from the coded data. A theoretical approach to the design of a digital phase-locked loop circuit operation at 1 and 50 MHz is described. Hardware implementation of a breadboard design to function at 1 MHz and a printed-circuit board designed to function at 50 MHz were assembled using emitter coupled logic (ECL) to verify experimentally the theoretical design.

Phase-lock-loop application for fiber optic receiver

NASA Technical Reports Server (NTRS)

Ruggles, Stephen L.; Wills, Robert W.

1991-01-01

Phase-locked loop circuits are frequently employed in communication systems. In recent years, digital phase-locked loop circuits were utilized in optical communications systems. In an optical transceiver system, the digital phase-locked loop circuit is connected to the output of the receiver to extract a clock signal from the received coded data (NRZ, Bi-Phase, or Manchester). The clock signal is then used to reconstruct or recover the original data from the coded data. A theoretical approach to the design of a digital phase-locked loop circuit operation at 1 and 50 MHz is described. Hardware implementation of a breadboard design to function at 1 MHz and a printed-circuit board designed to function at 50 MHz were assembled using emitter coupled logic (ECL) to verify experimentally the theoretical design.

High-density interconnect substrates and device packaging using conductive composites

NASA Astrophysics Data System (ADS)

Gandhi, Pradeep; Gallagher, Catherine; Matijasevic, Goran

1998-02-01

High-end printed circuit board manufacturing technology is receiving increasing attention due to higher functionality in smaller form factors. This is evident from the industry efforts to produced reliable microvias and related trace features to pack as much circuit density as possible. Cost, density and performance requirements have prodded entry into a market that was mainly reserved for ceramic and molded packages for the last forty years. To successfully meet the demanding specifications of this market segment, a worldwide effort is underway for the development of new materials, processes and equipment. A novel base technology that is applicable to most of the major packaging and redistribution elements in an electronic module is presented.High density multilayer circuits with landless blind and buried vias can be fabricated by filling the conductor paste into photoimaged dielectrics and thermally processing it at a relatively lower temperature. Via layers are prepared directly on the inherently planarized circuit layer in an identical fashion. Because these composite materials are applied in an additive fabrication method, metal substrates can be employed for high thermal dissipation and excellent CTE control over a wide temperature range. The conductor material is based on interpenetrating polymer and metal networks that are formed in situ from metal particles and a thermosetting flux/binder. The metal network is formed when the alloy particles melt and react with adjacent high melting point metal particle. Interaction also occurs between the alloy particles and pad, lead or previous trace metallizations provided they are solderable by alloys of tin. The new alloy composition created by the interdiffusion process within the bulk material has a higher melting point than the original alloy and thus solidifies immediately upon formation. This metallurgical reaction, known as transient liquid phase sintering, is facilitated by the polymer mixture. INtegration of the polymer and metal networks is maintained by utilizing a thermosetting polymer system that cures simultaneously with the metallurgical reaction. Although similar in concept and performance to cermet inks, these compositions differ in that their process temperatures are compatible with conventional printed wiring board materials and that the polymeric binder remains to provide adhesion and fatigue resistance to the metallurgical network.

Flexible CMOS-Like Circuits Based on Printed P-Type and N-Type Carbon Nanotube Thin-Film Transistors.

PubMed

Zhang, Xiang; Zhao, Jianwen; Dou, Junyan; Tange, Masayoshi; Xu, Weiwei; Mo, Lixin; Xie, Jianjun; Xu, Wenya; Ma, Changqi; Okazaki, Toshiya; Cui, Zheng

2016-09-01

P-type and n-type top-gate carbon nanotube thin-film transistors (TFTs) can be selectively and simultaneously fabricated on the same polyethylene terephthalate (PET) substrate by tuning the types of polymer-sorted semiconducting single-walled carbon nanotube (sc-SWCNT) inks, along with low temperature growth of HfO 2 thin films as shared dielectric layers. Both the p-type and n-type TFTs show good electrical properties with on/off ratio of ≈10 5 , mobility of ≈15 cm 2 V -1 s -1 , and small hysteresis. Complementary metal oxide semiconductor (CMOS)-like logic gates and circuits based on as-prepared p-type and n-type TFTs have been achieved. Flexible CMOS-like inverters exhibit large noise margin of 84% at low voltage (1/2 V dd = 1.5 V) and maximum voltage gain of 30 at V dd of 1.5 V and low power consumption of 0.1 μW. Both of the noise margin and voltage gain are one of the best values reported for flexible CMOS-like inverters at V dd less than 2 V. The printed CMOS-like inverters work well at 10 kHz with 2% voltage loss and delay time of ≈15 μs. A 3-stage ring oscillator has also been demonstrated on PET substrates and the oscillation frequency of 3.3 kHz at V dd of 1 V is achieved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

New Discrete Fibonacci Charge Pump Design, Evaluation and Measurement

NASA Astrophysics Data System (ADS)

Matoušek, David; Hospodka, Jiří; Šubrt, Ondřej

2017-06-01

This paper focuses on the practical aspects of the realisation of Dickson and Fibonacci charge pumps. Standard Dickson charge pump circuit solution and new Fibonacci charge pump implementation are compared. Both charge pumps were designed and then evaluated by LTspice XVII simulations and realised in a discrete form on printed circuit board (PCB). Finally, the key parameters as the output voltage, efficiency, rise time, variable power supply and clock frequency effects were measured.

Designing an Electronics Data Package for Printed Circuit Boards (PCBs)

DTIC Science & Technology

2013-08-01

finished PCB flatness deviation should be less than 0.010 inches per inch. 4  The minimum copper wall thickness of plated-thru holes should be...Memory Card International Association)  IPC-6015 MCM-L (Multi-Chip Module – Laminated )  IPC-6016 HDI (High Density Interconnect)  IPC-6018...Interconnect ICT In Circuit Tester IPC Association Connecting Electronics Industries MCM-L Multi-Chip Module – Laminated MIL Military NEMA National

77 FR 46024 - Foreign-Trade Zone 8-Toledo, OH; Notification of Proposed Production Activity, Whirlpool...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-02

..., AC motors, power supplies, heater tubs, LED light assemblies, triple level and push button switches, control panels, printed circuit boards, power cords, wire harnesses, EMI filters, pressure sensors...

High-Throughput Fabrication of Flexible and Transparent All-Carbon Nanotube Electronics.

PubMed

Chen, Yong-Yang; Sun, Yun; Zhu, Qian-Bing; Wang, Bing-Wei; Yan, Xin; Qiu, Song; Li, Qing-Wen; Hou, Peng-Xiang; Liu, Chang; Sun, Dong-Ming; Cheng, Hui-Ming

2018-05-01

This study reports a simple and effective technique for the high-throughput fabrication of flexible all-carbon nanotube (CNT) electronics using a photosensitive dry film instead of traditional liquid photoresists. A 10 in. sized photosensitive dry film is laminated onto a flexible substrate by a roll-to-roll technology, and a 5 µm pattern resolution of the resulting CNT films is achieved for the construction of flexible and transparent all-CNT thin-film transistors (TFTs) and integrated circuits. The fabricated TFTs exhibit a desirable electrical performance including an on-off current ratio of more than 10 5 , a carrier mobility of 33 cm 2 V -1 s -1 , and a small hysteresis. The standard deviations of on-current and mobility are, respectively, 5% and 2% of the average value, demonstrating the excellent reproducibility and uniformity of the devices, which allows constructing a large noise margin inverter circuit with a voltage gain of 30. This study indicates that a photosensitive dry film is very promising for the low-cost, fast, reliable, and scalable fabrication of flexible and transparent CNT-based integrated circuits, and opens up opportunities for future high-throughput CNT-based printed electronics.

Encapsulate-and-peel: fabricating carbon nanotube CMOS integrated circuits in a flexible ultra-thin plastic film.

PubMed

Gao, Pingqi; Zhang, Qing

2014-02-14

Fabrication of single-walled carbon nanotube thin film (SWNT-TF) based integrated circuits (ICs) on soft substrates has been challenging due to several processing-related obstacles, such as printed/transferred SWNT-TF pattern and electrode alignment, electrical pad/channel material/dielectric layer flatness, adherence of the circuits onto the soft substrates etc. Here, we report a new approach that circumvents these challenges by encapsulating pre-formed SWNT-TF-ICs on hard substrates into polyimide (PI) and peeling them off to form flexible ICs on a large scale. The flexible SWNT-TF-ICs show promising performance comparable to those circuits formed on hard substrates. The flexible p- and n-type SWNT-TF transistors have an average mobility of around 60 cm(2) V(-1) s(-1), a subthreshold slope as low as 150 mV dec(-1), operating gate voltages less than 2 V, on/off ratios larger than 10(4) and a switching speed of several kilohertz. The post-transfer technique described here is not only a simple and cost-effective pathway to realize scalable flexible ICs, but also a feasible method to fabricate flexible displays, sensors and solar cells etc.

Preparation of solid silver nanoparticles for inkjet printed flexible electronics with high conductivity.

PubMed

Shen, Wenfeng; Zhang, Xianpeng; Huang, Qijin; Xu, Qingsong; Song, Weijie

2014-01-01

Silver nanoparticles (NPs) which could be kept in solid form and were easily stored without degeneration or oxidation at room temperature for a long period of time were synthesized by a simple and environmentally friendly wet chemistry method in an aqueous phase. Highly stable dispersions of aqueous silver NP inks, sintered at room temperature, for printing highly conductive tracks (∼8.0 μΩ cm) were prepared simply by dispersing the synthesized silver NP powder in water. These inks are stable, fairly homogeneous and suitable for a wide range of patterning techniques. The inks were successfully printed on paper and polyethylene terephthalate (PET) substrates using a common color printer. Upon annealing at 180 °C, the resistivity of the printed silver patterns decreased to 3.7 μΩ cm, which is close to twice that of bulk silver. Various factors affecting the resistivity of the printed silver patterns, such as annealing temperature and the number of printing cycles, were investigated. The resulting high conductivity of the printed silver patterns reached over 20% of the bulk silver value under ambient conditions, which enabled the fabrication of flexible electronic devices, as demonstrated by the inkjet printing of conductive circuits of LED devices.

A new crank arm based load cell, with built-in conditioning circuit and strain gages, to measure the components of the force applied by a cyclist.

PubMed

Pigatto, Andre V; Moura, Karina O A; Favieiro, Gabriela W; Balbinot, Alexandre

2016-08-01

This report describes the development of a force platform based on instrumented load cells with built-in conditioning circuit and strain gages to measure and acquire the components of the force that is applied to the bike crank arm during pedaling in real conditions, and save them on a SD Card. To accomplish that, a complete new crank arm 3D solid model was developed in the SolidWorks, with dimensions equivalent to a commercial crank set and compatible with a conventional road bike, but with a compartment to support all the electronics necessary to measure 3 components of the force applied to the pedal during pedaling. After that, a 6082 T6 Aluminum Crankset based on the solid model was made and instrumented with three Wheatstone bridges each. The signals were conditioned on a printed circuit board, made on SMD technology, and acquired using a microcontroller with a DAC. Static deformation analysis showed a linearity error below 0.6% for all six channels. Dynamic analysis showed a natural frequency above 136Hz. A one-factor experiment design was performed with 5 amateur cyclists. ANOVA showed that the cyclist weight causes significant variation on the force applied to the bicycle pedal and its bilateral symmetry.

Bifacial aspects of industrial n-Pasha solar cells

NASA Astrophysics Data System (ADS)

Van Aken, Bas B.; Tool, Kees; Kossen, Eric J.; Carr, Anna J.; Janssen, Gaby J. M.; Newman, Bonna K.; Romijn, Ingrid G.

2017-08-01

Bifacial photovoltaic (PV) modules make optimal use of diffuse and ground-reflected light. The gain in energy yield depends on both the local climatic conditions and the PV system layout. These determine the additional irradiance on the rear of the PV panels. The rear response of the (laminated) solar cell(s) determines how much additional energy this rear irradiance generates. Based on our experiments and simulations, the main parameters that determine the bifaciality factor of solar cells with a front side junction are the rear metal coverage, the base resistivity and the diffusion profile on the rear. These will be evaluated and discussed in this paper. Front-junction solar cells with low base resistivity have a lower short circuit current when illuminated from the rear due to enhanced recombination in the BSF. Stencil printed rear metallization yields a higher bifaciality factor compared to screen printed by reducing the metal coverage and consumption and maintaining the front side efficiency. For our optimized 239 cm2 bifacial cell we estimate that the output with 20% contributed by the rear side is equivalent to that of a 24.4% efficient monofacial cell.

Control of Evaporation Behavior of an Inkjet-Printed Dielectric Layer Using a Mixed-Solvent System

NASA Astrophysics Data System (ADS)

Yang, Hak Soon; Kang, Byung Ju; Oh, Je Hoon

2016-01-01

In this study, the evaporation behavior and the resulting morphology of inkjet-printed dielectric layers were controlled using a mixed-solvent system to fabricate uniform poly-4-vinylphenol (PVP) dielectric layers without any pinholes. The mixed-solvent system consisted of two different organic solvents: 1-hexanol and ethanol. The effects of inkjet-printing variables such as overlap condition, substrate temperature, and different printing sequences (continuous and interlacing printing methods) on the inkjet-printed dielectric layer were also investigated. Increasing volume fraction of ethanol (VFE) is likely to reduce the evaporation rate gradient and the drying time of the inkjet-printed dielectric layer; this diminishes the coffee stain effect and thereby improves the uniformity of the inkjet-printed dielectric layer. However, the coffee stain effect becomes more severe with an increase in the substrate temperature due to the enhanced outward convective flow. The overlap condition has little effect on the evaporation behavior of the printed dielectric layer. In addition, the interlacing printing method results in either a stronger coffee stain effect or wavy structures of the dielectric layers depending on the VFE of the PVP solution. All-inkjet-printed capacitors without electrical short circuiting can be successfully fabricated using the optimized PVP solution (VFE = 0.6); this indicates that the mixed-solvent system is expected to play an important role in the fabrication of high-quality inkjet-printed dielectric layers in various printed electronics applications.

Unitary Shaft-Angle and Shaft-Speed Sensor Assemblies

NASA Technical Reports Server (NTRS)

Alhorn, Dean C.; Howard, David E.; Smith, Dennis A.

2006-01-01

The figure depicts a unit that contains a rotary-position or a rotary-speed sensor, plus electronic circuitry necessary for its operation, all enclosed in a single housing with a shaft for coupling to an external rotary machine. This rotation sensor unit is complete: when its shaft is mechanically connected to that of the rotary machine and it is supplied with electric power, it generates an output signal directly indicative of the rotary position or speed, without need for additional processing by other circuitry. The incorporation of all of the necessary excitatory and readout circuitry into the housing (in contradistinction to using externally located excitatory and/or readout circuitry) in a compact arrangement is the major difference between this unit and prior rotation-sensor units. The sensor assembly inside the housing includes excitatory and readout integrated circuits mounted on a circular printed-circuit board. In a typical case in which the angle or speed transducer(s) utilize electromagnetic induction, the assembly also includes another circular printed-circuit board on which the transducer windings are mounted. A sheet of high-magnetic permeability metal ("mu metal") is placed between the winding board and the electronic-circuit board to prevent spurious coupling of excitatory signals from the transducer windings to the readout circuits. The housing and most of the other mechanical hardware can be common to a variety of different sensor designs. Hence, the unit can be configured to generate any of variety of outputs by changing the interior sensor assembly. For example, the sensor assembly could contain an analog tachometer circuit that generates an output proportional (in both magnitude and sign or in magnitude only) to the speed of rotation.

Design guidelines for advanced LSI microcircuit packaging using thick film multilayer technology

NASA Technical Reports Server (NTRS)

Peckinpaugh, C. J.

1974-01-01

Ceramic multilayer circuitry results from the sequential build-up of two or more layers of pre-determined conductive interconnections separated by dielectric layers and fired at an elevated temperature to form a solidly fused structure. The resultant ceramic interconnect matrix is used as a base to mount active and passive devices and provide the necessary electrical interconnection to accomplish the desired electrical circuit. Many methods are known for developing multilevel conductor mechanisms such as multilayer printed circuits, welded wire matrices, flexible copper tape conductors, and thin and thick-film ceramic multilayers. Each method can be considered as a specialized field with each possessing its own particular set of benefits and problems. This design guide restricts itself to the art of design, fabrication and assembly of ceramic multilayer circuitry and the reliability of the end product.

Evaluation of gold and silver leaching from printed circuit board of cellphones

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petter, P.M.H., E-mail: patymhp@yahoo.com.br; Veit, H.M.; Bernardes, A.M.

2014-02-15

Highlights: • Printed circuit boards (PCB) of mobile phones have large amounts of metals with high economic value such as gold and silver. • Dissolution of gold was done with a cyanide-based reagent and silver with nitric acid. • Leaching of PCB with Na{sub 2}S{sub 2}O{sub 3} and (NH{sub 4}){sub 2}S{sub 2}O{sub 3} to examine the feasibility of using these reagents was done. - Abstract: Electronic waste has been increasing proportionally with the technology. So, nowadays, it is necessary to consider the useful life, recycling, and final disposal of these equipment. Metals, such as Au, Ag, Cu, Sn and Nimore » can be found in the printed circuit boards (PCB). According to this, the aims of this work is to characterize the PCBs of mobile phones with aqua regia; obtaining “reference” values of leaching, to gold and silver, with cyanide and nitric acid, respectively; and study the process of leaching of these metals in alternative leaching with sodium thiosulfate and ammonium thiosulfate. The metals were characterized by digesting the sample with aqua regia for 1 and 2 h at 60 °C and 80 °C. The leaching of Au with a commercial reagent (cyanide) and the Ag with HNO{sub 3}were made. The leaching of Au and Ag with alternative reagents: Na{sub 2}S{sub 2}O{sub 3,} and (NH{sub 4}){sub 2}S{sub 2}O{sub 3} in 0.1 M concentration with the addition of CuSO{sub 4}, NH{sub 4}OH, and H{sub 2}O{sub 2}, was also studied. The results show that the digestion with aqua regia was efficient to characterize the metals present in the PCBs of mobile phones. However, the best method to solubilize silver was by digesting the sample with nitric acid. The leaching process using sodium thiosulfate was more efficient when an additional concentration of 0.015 and 0.030 M of the CuSO{sub 4} was added.« less

Electronically conducting polymers with silver grains

NASA Technical Reports Server (NTRS)

Murphy, Oliver J. (Inventor); Hitchens, G. Duncan (Inventor); Hodko, Dolibor (Inventor)

1999-01-01

The present invention provides electronically conducting polymer films formed from photosensitive formulations of pyrrole and an electron acceptor that have been selectively exposed to UV light, laser light, or electron beams. The formulations may include photoinitiators, flexibilizers, solvents and the like. These solutions can be used in applications including printed circuit boards and through-hole plating and enable direct metallization processes on non-conducting substrates. After forming the conductive polymer patterns, a printed wiring board can be formed by sensitizing the polymer with palladium and electrolytically depositing copper.

Method for Fabricating and Packaging an M.Times.N Phased-Array Antenna

NASA Technical Reports Server (NTRS)

Xu, Xiaochuan (Inventor); Chen, Yihong (Inventor); Chen, Ray T. (Inventor); Subbaraman, Harish (Inventor)

2017-01-01

A method for fabricating an M.times.N, P-bit phased-array antenna on a flexible substrate is disclosed. The method comprising ink jet printing and hardening alignment marks, antenna elements, transmission lines, switches, an RF coupler, and multilayer interconnections onto the flexible substrate. The substrate of the M.times.N, P-bit phased-array antenna may comprise an integrated control circuit of printed electronic components such as, photovoltaic cells, batteries, resistors, capacitors, etc. Other embodiments are described and claimed.

Anvil for Flaring PCB Guide Pins

NASA Technical Reports Server (NTRS)

Winn, E.; Turner, R.

1985-01-01

Spring-loaded anvil results in fewer fractured pins. New anvil for flaring guide pins in printed-circuit boards absorbs approximately 80 percent of press force. As result fewer pins damaged, and work output of flaring press greatly increased.

48 CFR 1819.1005 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Printed Circuit Assembly (Electronic Assembly) Manufacturing. 334613 Magnetic and Optical Recording Media... and Wireless Communication Equipment Manufacturing. 336415 Guided Missile and Space Vehicle Propulsion Unit and Propulsion Unit Parts Manufacturing. 336419 Other Guided Missile and Space Vehicle Parts and...

48 CFR 1819.1005 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Printed Circuit Assembly (Electronic Assembly) Manufacturing. 334613 Magnetic and Optical Recording Media... and Wireless Communication Equipment Manufacturing. 336415 Guided Missile and Space Vehicle Propulsion Unit and Propulsion Unit Parts Manufacturing. 336419 Other Guided Missile and Space Vehicle Parts and...

Thermal decomposition of electronic wastes: Mobile phone case and other parts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Molto, Julia, E-mail: julia.molto@ua.es; Egea, Silvia; Conesa, Juan Antonio

Highlights: > Pyrolysis and combustion of different parts of mobile phones produce important quantities of CO and CO{sub 2}. > Naphthalene is the most abundant PAH obtained in the thermal treatment of mobile phones. > Higher combustion temperature increases the chlorinated species evolved. - Abstract: Pyrolysis and combustion runs at 850 {sup o}C in a horizontal laboratory furnace were carried out on different parts of a mobile phone (printed circuit board, mobile case and a mixture of both materials). The analyses of the carbon oxides, light hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), polychlorodibenzo-p-dioxin, polychlorodibenzofurans (PCDD/Fs), and dioxin-like PCBs are shown. Regardingmore » semivolatile compounds, phenol, styrene, and its derivatives had the highest yields. In nearly all the runs the same PAHs were identified, naphthalene being the most common component obtained. Combustion of the printed circuit board produced the highest emission factor of PCDD/Fs, possibly due to the high copper content.« less

Integrated bioleaching of copper metal from waste printed circuit board-a comprehensive review of approaches and challenges.

PubMed

Awasthi, Abhishek Kumar; Zeng, Xianlai; Li, Jinhui

2016-11-01

Waste electrical and electronic equipment (e-waste) is the most rapidly growing waste stream in the world, and the majority of the residues are openly disposed of in developing countries. Waste printed circuit boards (WPCBs) make up the major portion of e-waste, and their informal recycling can cause environmental pollution and health risks. Furthermore, the conventional disposal and recycling techniques-mechanical treatments used to recover valuable metals, including copper-are not sustainable in the long term. Chemical leaching is rapid and efficient but causes secondary pollution. Bioleaching is a promising approach, eco-friendly and economically feasible, but it is slower process. This review considers the recycling potential of microbes and suggests an integrated bioleaching approach for Cu extraction and recovery from WPCBs. The proposed recycling system should be more effective, efficient and both technically and economically feasible.

FDTD Calculation of FM-Band Crosstalks between Perpendicular Traces on Printed Circuit Board with Ground-Pattern Slits

NASA Astrophysics Data System (ADS)

Ueyama, Hiroya; Maeno, Tsuyoshi; Hirata, Akimasa; Wang, Jianqing; Fujiwara, Osamu

Electromagnetic disturbances for vehicle-mounted radios are well known to be caused mainly by conduction noise currents flowing out wire harnesses from printed circuit boards (PCBs) having a common ground layer with slits. In this study, in order to investigate how ground-layer slits affect the above conduction noise currents, we paid FM band induced voltages or crosstalks on the trace connected to the wire harnesss, and simulated with the FDTD method the crosstalk levels between two traces perpendicularly fabricated on three kinds of simple PCBs with different ground-layer slits, which were compared with measurement in the frequency range from 10 MHz to 1 GHz. As a result, we could confirm that the FDTD calculation approximately agrees with the measured results, and also that the crosstalk levels do not always increase with the slit number, which can be reduced by the slit layout.

Effective algorithm for routing integral structures with twolayer switching

NASA Astrophysics Data System (ADS)

Nazarov, A. V.; Shakhnov, V. A.; Vlasov, A. I.; Novikov, A. N.

2018-05-01

The paper presents an algorithm for routing switching objects such as large-scale integrated circuits (LSICs) with two layers of metallization, embossed printed circuit boards, microboards with pairs of wiring layers on each side, and other similar constructs. The algorithm allows eliminating the effect of mutual blocking of routes in the classical wave algorithm by implementing a special circuit of digital wave motion in two layers of metallization, allowing direct intersections of all circuit conductors in a combined layer. However, information about the belonging of the topology elements to the circuits is sufficient for layering and minimizing the number of contact holes. In addition, the paper presents a specific example which shows that, in contrast to the known routing algorithms using a wave model, just one byte of memory per discrete of the work field is sufficient to implement the proposed algorithm.

Structural Integration of Silicon Solar Cells and Lithium-ion Batteries Using Printed Electronics

NASA Astrophysics Data System (ADS)

Kang, Jin Sung

Inkjet printing of electrode using copper nanoparticle ink is presented. Electrode was printed on a flexible glass epoxy composite substrate using drop on demand piezoelectric dispenser and was sintered at 200°C in N 2 gas condition. The printed electrodes were made with various widths and thicknesses. Surface morphology of electrode was analyzed using scanning electron microscope (SEM) and atomic force microscope (AFM). Reliable dimensions for printed electronics were found from this study. Single-crystalline silicon solar cells were tested under four-point bending to find the feasibility of directly integrating them onto a carbon fiber/epoxy composite laminate. These solar cells were not able to withstand 0.2% strain. On the other hand, thin-film amorphous silicon solar cells were subjected to flexural fatigue loadings. The current density-voltage curves were analyzed at different cycles, and there was no noticeable degradation on its performance up to 100 cycles. A multifunctional composite laminate which can harvest and store solar energy was fabricated using printed electrodes. The integrated printed circuit board (PCB) was co-cured with a carbon/epoxy composite laminate by the vacuum bag molding process in an autoclave; an amorphous silicon solar cell and a thin-film solid state lithium-ion (Li-ion) battery were adhesively joined and electrically connected to a thin flexible PCB; and then the passive components such as resistors and diodes were electrically connected to the printed circuit board by silver pasting. Since a thin-film solid state Li-ion battery was not able to withstand tensile strain above 0.4%, thin Li-ion polymer batteries were tested under various mechanical loadings and environmental conditions to find the feasibility of using the polymer batteries for our multifunctional purpose. It was found that the Li-ion polymer batteries were stable under pressure and tensile loading without any noticeable degradation on its charge and discharge performances. Also, the active materials did not decompose at 80°C, and the battery was performing well under low temperature of -27°C. Lastly, the batteries were embedded inside a carbon fiber/epoxy composite laminate to characterize their performance under fatigue loading. Finally, an intense pulsed light (IPL) was used to sinter printed silver nanoink patterns. X-ray diffraction (XRD) was used to find grain size of printed silver nanoink patterns. From these analyses it was confirmed that IPL is able to adequately sinter silver nanoink patterns for printed electronics without degradation of the substrates in less than 30 ms.

Delay grid multiplexing: simple time-based multiplexing and readout method for silicon photomultipliers

NASA Astrophysics Data System (ADS)

Won, Jun Yeon; Ko, Guen Bae; Lee, Jae Sung

2016-10-01

In this paper, we propose a fully time-based multiplexing and readout method that uses the principle of the global positioning system. Time-based multiplexing allows simplifying the multiplexing circuits where the only innate traces that connect the signal pins of the silicon photomultiplier (SiPM) channels to the readout channels are used as the multiplexing circuit. Every SiPM channel is connected to the delay grid that consists of the traces on a printed circuit board, and the inherent transit times from each SiPM channel to the readout channels encode the position information uniquely. Thus, the position of each SiPM can be identified using the time difference of arrival (TDOA) measurements. The proposed multiplexing can also allow simplification of the readout circuit using the time-to-digital converter (TDC) implemented in a field-programmable gate array (FPGA), where the time-over-threshold (ToT) is used to extract the energy information after multiplexing. In order to verify the proposed multiplexing method, we built a positron emission tomography (PET) detector that consisted of an array of 4  ×  4 LGSO crystals, each with a dimension of 3  ×  3  ×  20 mm3, and one- to-one coupled SiPM channels. We first employed the waveform sampler as an initial study, and then replaced the waveform sampler with an FPGA-TDC to further simplify the readout circuits. The 16 crystals were clearly resolved using only the time information obtained from the four readout channels. The coincidence resolving times (CRTs) were 382 and 406 ps FWHM when using the waveform sampler and the FPGA-TDC, respectively. The proposed simple multiplexing and readout methods can be useful for time-of-flight (TOF) PET scanners.

Methods for increasing noise immunity of radio electronic systems with redundancy

NASA Astrophysics Data System (ADS)

Orlov, P. E.; Medvedev, A. V.; Sharafutdinov, V. R.; Gazizov, T. R.; Ubaichin, A. V.

2018-05-01

The idea of increasing the noise immunity of radioelectronic systems with redundancy is presented. Specific technical solutions based on this idea of modal redundancy are described. An estimation of noise immunity improvement was performed by the example of implementation of modal redundancy with the broad-side electromagnetic coupling for a printed circuit board of the digital signal processing unit for an autonomous navigation system of a spacecraft. It is shown that the implementation of modal redundancy can provide an attenuation coefficient for the interference signal up to 12 dB.

New technology for recovering residual metals from nonmetallic fractions of waste printed circuit boards.

PubMed

Zhang, Guangwen; He, Yaqun; Wang, Haifeng; Zhang, Tao; Wang, Shuai; Yang, Xing; Xia, Wencheng

2017-06-01

Recycling of waste printed circuit boards is important for environmental protection and sustainable resource utilization. Corona electrostatic separation has been widely used to recycle metals from waste printed circuit boards, but it has poor separation efficiency for finer sized fractions. In this study, a new process of vibrated gas-solid fluidized bed was used to recycle residual metals from nonmetallic fractions, which were treated using the corona electrostatic separation technology. The effects of three main parameters, i.e., vibration frequency, superficial air flow velocity, and fluidizing time on gravity segregation, were investigated using a vibrating gas-solid fluidized bed. Each size fraction had its own optimum parameters. Corresponding to their optimal segregation performance, the products from each experiment were analyzed using an X-ray fluorescence (XRF) and a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS). From the results, it can be seen that the metal recoveries of -1+0.5mm, -0.5+0.25mm, and -0.25mm size fractions were 86.39%, 82.22% and 76.63%, respectively. After separation, each metal content in the -1+0.5 or -0.5+0.25mm size fraction reduced to 1% or less, while the Fe and Cu contents are up to 2.57% and 1.50%, respectively, in the -0.25mm size fraction. Images of the nonmetallic fractions with a size of -0.25mm indicated that a considerable amount of clavate glass fibers existed in these nonmetallic fractions, which may explain why fine particles had the poorest segregation performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamic and Tunable Threshold Voltage in Organic Electrochemical Transistors.

PubMed

Doris, Sean E; Pierre, Adrien; Street, Robert A

2018-04-01

In recent years, organic electrochemical transistors (OECTs) have found applications in chemical and biological sensing and interfacing, neuromorphic computing, digital logic, and printed electronics. However, the incorporation of OECTs in practical electronic circuits is limited by the relative lack of control over their threshold voltage, which is important for controlling the power consumption and noise margin in complementary and unipolar circuits. Here, the threshold voltage of OECTs is precisely tuned over a range of more than 1 V by chemically controlling the electrochemical potential at the gate electrode. This threshold voltage tunability is exploited to prepare inverters and amplifiers with improved noise margin and gain, respectively. By coupling the gate electrode with an electrochemical oscillator, single-transistor oscillators based on OECTs with dynamic time-varying threshold voltages are prepared. This work highlights the importance of electrochemistry at the gate electrode in determining the electrical properties of OECTs, and opens a path toward the system-level design of low-power OECT-based electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Merging parallel optics packaging and surface mount technologies

NASA Astrophysics Data System (ADS)

Kopp, Christophe; Volpert, Marion; Routin, Julien; Bernabé, Stéphane; Rossat, Cyrille; Tournaire, Myriam; Hamelin, Régis

2008-02-01

Optical links are well known to present significant advantages over electrical links for very high-speed data rate at 10Gpbs and above per channel. However, the transition towards optical interconnects solutions for short and very short reach applications requires the development of innovative packaging solutions that would deal with very high volume production capability and very low cost per unit. Moreover, the optoelectronic transceiver components must be able to move from the edge to anywhere on the printed circuit board, for instance close to integrated circuits with high speed IO. In this paper, we present an original packaging design to manufacture parallel optic transceivers that are surface mount devices. The package combines highly integrated Multi-Chip-Module on glass and usual IC ceramics packaging. The use of ceramic and the development of sealing technologies achieve hermetic requirements. Moreover, thanks to a chip scale package approach the final device exhibits a much minimized footprint. One of the main advantages of the package is its flexibility to be soldered or plugged anywhere on the printed circuit board as any other electronic device. As a demonstrator we present a 2 by 4 10Gbps transceiver operating at 850nm.

Analysis of microstrip dipoles and slots transversely coupled to a microstrip line using the FDTD method

NASA Technical Reports Server (NTRS)

Tulintseff, A. N.

1993-01-01

Printed dipole elements and their complement, linear slots, are elementary radiators that have found use in low-profile antenna arrays. Low-profile antenna arrays, in addition to their small size and low weight characteristics, offer the potential advantage of low-cost, high-volume production with easy integration with active integrated circuit components. The design of such arrays requires that the radiation and impedance characteristics of the radiating elements be known. The FDTD (Finite-Difference Time-Domain) method is a general, straight-forward implementation of Maxwell's equations and offers a relatively simple way of analyzing both printed dipole and slot elements. Investigated in this work is the application of the FDTD method to the analysis of printed dipole and slot elements transversely coupled to an infinite transmission line in a multilayered configuration. Such dipole and slot elements may be used in dipole and slot series-fed-type linear arrays, where element offsets and interelement line lengths are used to obtain the desired amplitude distribution and beam direction, respectively. The design of such arrays is achieved using transmission line theory with equivalent circuit models for the radiating elements. In an equivalent circuit model, the dipole represents a shunt impedance to the transmission line, where the impedance is a function of dipole offset, length, and width. Similarly, the slot represents a series impedance to the transmission line. The FDTD method is applied to single dipole and slot elements transversely coupled to an infinite microstrip line using a fixed rectangular grid with Mur's second order absorbing boundary conditions. Frequency-dependent circuit and scattering parameters are obtained by saving desired time-domain quantities and using the Fourier transform. A Gaussian pulse excitation is applied to the microstrip transmission line, where the resulting reflected signal due to the presence of the radiating element is used to determine the equivalent element impedance.

An Optimization System with Parallel Processing for Reducing Common-Mode Current on Electronic Control Unit

NASA Astrophysics Data System (ADS)

Okazaki, Yuji; Uno, Takanori; Asai, Hideki

In this paper, we propose an optimization system with parallel processing for reducing electromagnetic interference (EMI) on electronic control unit (ECU). We adopt simulated annealing (SA), genetic algorithm (GA) and taboo search (TS) to seek optimal solutions, and a Spice-like circuit simulator to analyze common-mode current. Therefore, the proposed system can determine the adequate combinations of the parasitic inductance and capacitance values on printed circuit board (PCB) efficiently and practically, to reduce EMI caused by the common-mode current. Finally, we apply the proposed system to an example circuit to verify the validity and efficiency of the system.

Flexible micro flow sensor for micro aerial vehicles

NASA Astrophysics Data System (ADS)

Zhu, Rong; Que, Ruiyi; Liu, Peng

2017-12-01

This article summarizes our studies on micro flow sensors fabricated on a flexible polyimide circuit board by a low-cost hybrid process of thin-film deposition and circuit printing. The micro flow sensor has merits of flexibility, structural simplicity, easy integrability with circuits, and good sensing performance. The sensor, which adheres to an object surface, can detect the surface flow around the object. In our study, we install the fabricated micro flow sensors on micro aerial vehicles (MAVs) to detect the surface flow variation around the aircraft wing and deduce the aerodynamic parameters of the MAVs in flight. Wind tunnel experiments using the sensors integrated with the MAVs are also conducted.

Fixture facilitates soldering operations

NASA Technical Reports Server (NTRS)

White, C. M.

1968-01-01

Soldering fixture, designed for printed circuit cards, is a basic bench-mounted, self-contained integral unit combining all soldering needs into a compact, readily available work station. All tools, materials, and accessories are available to provide an ideal station to perform critical soldering.

Hazardous Waste Cleanup: General Electric - Auburn Plant in Auburn, New York

EPA Pesticide Factsheets

GE purchased the property at Genesee Street in 1951 and constructed a manufacturing plant that produced a variety of electrical components including radar equipment, printed circuit boards and high voltage semiconductors. In January 1986, Powerex, Inc.,

Microstructure-tunable highly conductive graphene-metal composites achieved by inkjet printing and low temperature annealing

NASA Astrophysics Data System (ADS)

Zhao, Jie; Song, Man; Wen, Chenyu; Majee, Subimal; Yang, Dong; Wu, Biao; Zhang, Shi-Li; Zhang, Zhi-Bin

2018-03-01

We present a method for fabricating highly conductive graphene-silver composite films with a tunable microstructure achieved by means of an inkjet printing process and low temperature annealing. This is implemented by starting from an aqueous ink formulation using a reactive silver solution mixed with graphene nanoplatelets (GNPs), followed by inkjet printing deposition and annealing at 100 °C for silver formation. Due to the hydrophilic surfaces and the aid of a polymer stabilizer in an aqueous solution, the GNPs are uniformly covered with a silver layer. Simply by adjusting the content of GNPs in the inks, highly conductive GNP/Ag composites (>106 S m-1), with their microstructure changed from a large-area porous network to a compact film, is formed. In addition, the printed composite films show superior quality on a variety of unconventional substrates compared to its counterpart without GNPs. The availability of composite films paves the way to the metallization in different printed devices, e.g. interconnects in printed circuits and electrodes in energy storage devices.

Print-and-play: a new paradigm for the nearly-instant aerospace system

NASA Astrophysics Data System (ADS)

Church, Kenneth H.; Newton, C. Michael; Marsh, Albert J.; MacDonald, Eric W.; Soto, Cassandra D.; Lyke, James C.

2010-04-01

Nanosatellites, in particular the sub-class of CubeSATs, will provide an ability to place multiple small satellites in space more efficiently than larger satellites, with the eventual expectation that they will compete against some of the roles played by traditional large satellites that are expensive to launch. In order to do this, it is necessary to decrease the weight and volume without decreasing the capabilities. At the same time, it is desirable to create systems extremely rapidly, less than a week from concept to orbit. The Air Force has been working on a concept termed "CubeFlow" which will be a web-based design flow for rapidly constructible CubeSAT systems. In CubeFlow, distributed suppliers create offerings (modules, software functions, for satellite bus and payloads) meeting standard size and interface specifications, which are registered as a living catalog to a design community within the web-based CubeFlow environment. The idea of allowing any interested parties to make circuits and sensors that simply and compatibly connect to a modular satellite carrier is going to change how satellites are developed and launched, promoting creative exploitation and reduced development time and costs. We extend the power of the CubeFlow framework by a concept we call "print-and-play." "Print-and-play" enriches the CubeFlow concept dramatically. Whereas the CubeFlow system is oriented to the brokering of pre-created offerings from a "plug-and-play" vendor community, the idea of "print-andplay" allows similar offerings to be created "from scratch," using web-based plug-ins to capture design requirements, which are communicated to rapid prototyping tools.

Content based image retrieval for matching images of improvised explosive devices in which snake initialization is viewed as an inverse problem

NASA Astrophysics Data System (ADS)

Acton, Scott T.; Gilliam, Andrew D.; Li, Bing; Rossi, Adam

2008-02-01

Improvised explosive devices (IEDs) are common and lethal instruments of terrorism, and linking a terrorist entity to a specific device remains a difficult task. In the effort to identify persons associated with a given IED, we have implemented a specialized content based image retrieval system to search and classify IED imagery. The system makes two contributions to the art. First, we introduce a shape-based matching technique exploiting shape, color, and texture (wavelet) information, based on novel vector field convolution active contours and a novel active contour initialization method which treats coarse segmentation as an inverse problem. Second, we introduce a unique graph theoretic approach to match annotated printed circuit board images for which no schematic or connectivity information is available. The shape-based image retrieval method, in conjunction with the graph theoretic tool, provides an efficacious system for matching IED images. For circuit imagery, the basic retrieval mechanism has a precision of 82.1% and the graph based method has a precision of 98.1%. As of the fall of 2007, the working system has processed over 400,000 case images.

Improvement of wireless power transmission efficiency of implantable subcutaneous devices by closed magnetic circuit mechanism.

PubMed

Jo, Sung-Eun; Joung, Sanghoon; Suh, Jun-Kyo Francis; Kim, Yong-Jun

2012-09-01

Induction coils were fabricated based on flexible printed circuit board for inductive transcutaneous power transmission. The coil had closed magnetic circuit (CMC) structure consisting of inner and outer magnetic core. The power transmission efficiency of the fabricated device was measured in the air and in vivo condition. It was confirmed that the CMC coil had higher transmission efficiency than typical air-core coil. The power transmission efficiency during a misalignment between primary coil and implanted secondary coil was also evaluated. The decrease of mutual inductance between the two coils caused by the misalignment led to a low efficiency of the inductive link. Therefore, it is important to properly align the primary coil and implanted secondary coil for effective power transmission. To align the coils, a feedback coil was proposed. This was integrated on the backside of the primary coil and enabled the detection of a misalignment of the primary and secondary coils. As a result of using the feedback coil, the primary and secondary coils could be aligned without knowledge of the position of the implanted secondary coil.

Testing interconnected VLSI circuits in the Big Viterbi Decoder

NASA Technical Reports Server (NTRS)

Onyszchuk, I. M.

1991-01-01

The Big Viterbi Decoder (BVD) is a powerful error-correcting hardware device for the Deep Space Network (DSN), in support of the Galileo and Comet Rendezvous Asteroid Flyby (CRAF)/Cassini Missions. Recently, a prototype was completed and run successfully at 400,000 or more decoded bits per second. This prototype is a complex digital system whose core arithmetic unit consists of 256 identical very large scale integration (VLSI) gate-array chips, 16 on each of 16 identical boards which are connected through a 28-layer, printed-circuit backplane using 4416 wires. Special techniques were developed for debugging, testing, and locating faults inside individual chips, on boards, and within the entire decoder. The methods are based upon hierarchical structure in the decoder, and require that chips or boards be wired themselves as Viterbi decoders. The basic procedure consists of sending a small set of known, very noisy channel symbols through a decoder, and matching observables against values computed by a software simulation. Also, tests were devised for finding open and short-circuited wires which connect VLSI chips on the boards and through the backplane.

Current Perspectives on the Cerebellum and Reading Development.

PubMed

Alvarez, Travis A; Fiez, Julie A

2018-05-03

The dominant neural models of typical and atypical reading focus on the cerebral cortex. However, Nicolson et al. (2001) proposed a model, the cerebellar deficit hypothesis, in which the cerebellum plays an important role in reading. To evaluate the evidence in support of this model, we qualitatively review the current literature and employ meta-analytic tools examining patterns of functional connectivity between the cerebellum and the cerebral reading network. We find evidence for a phonological circuit with connectivity between the cerebellum and a dorsal fronto-parietal pathway, and a semantic circuit with cerebellar connectivity to a ventral fronto-temporal pathway. Furthermore, both cerebral pathways have functional connections with the mid-fusiform gyrus, a region implicated in orthographic processing. Consideration of these circuits within the context of the current literature suggests the cerebellum is positioned to influence both phonological and word-based decoding procedures for recognizing unfamiliar printed words. Overall, multiple lines of research provide support for the cerebellar deficit hypothesis, while also highlighting the need for further research to test mechanistic hypotheses. Copyright © 2018. Published by Elsevier Ltd.

Fault Detection, Isolation and Recovery (FDIR) Portable Liquid Oxygen Hardware Demonstrator

NASA Technical Reports Server (NTRS)

Oostdyk, Rebecca L.; Perotti, Jose M.

2011-01-01

The Fault Detection, Isolation and Recovery (FDIR) hardware demonstration will highlight the effort being conducted by Constellation's Ground Operations (GO) to provide the Launch Control System (LCS) with system-level health management during vehicle processing and countdown activities. A proof-of-concept demonstration of the FDIR prototype established the capability of the software to provide real-time fault detection and isolation using generated Liquid Hydrogen data. The FDIR portable testbed unit (presented here) aims to enhance FDIR by providing a dynamic simulation of Constellation subsystems that feed the FDIR software live data based on Liquid Oxygen system properties. The LO2 cryogenic ground system has key properties that are analogous to the properties of an electronic circuit. The LO2 system is modeled using electrical components and an equivalent circuit is designed on a printed circuit board to simulate the live data. The portable testbed is also be equipped with data acquisition and communication hardware to relay the measurements to the FDIR application running on a PC. This portable testbed is an ideal capability to perform FDIR software testing, troubleshooting, training among others.

Double sided circuit board and a method for its manufacture

DOEpatents

Lindenmeyer, Carl W.

1989-01-01

Conductance between the sides of a large double sided printed circuit board is provided using a method which eliminates the need for chemical immersion or photographic exposure of the entire large board. A plurality of through-holes are drilled or punched in a substratum according to the desired pattern, conductive laminae are made to adhere to both sides of the substratum covering the holes and the laminae are pressed together and permanently joined within the holes, providing conductive paths.

Modified Coaxial Probe Feeds for Layered Antennas

NASA Technical Reports Server (NTRS)

Fink, Patrick W.; Chu, Andrew W.; Dobbins, Justin A.; Lin, Greg Y.

2006-01-01

In a modified configuration of a coaxial probe feed for a layered printed-circuit antenna (e.g., a microstrip antenna), the outer conductor of the coaxial cable extends through the thickness of at least one dielectric layer and is connected to both the ground-plane conductor and a radiator-plane conductor. This modified configuration simplifies the incorporation of such radio-frequency integrated circuits as power dividers, filters, and low-noise amplifiers. It also simplifies the design and fabrication of stacked antennas with aperture feeds.

Double sided circuit board and a method for its manufacture

DOEpatents

Lindenmeyer, C.W.

1988-04-14

Conductance between the sides of a large double sided printed circuit board is provided using a method which eliminates the need for chemical immersion or photographic exposure of the entire large board. A plurality of through-holes are drilled or punched in a substratum according to the desired pattern, conductive laminae are made to adhere to both sides of the substratum covering the holes and the laminae are pressed together and permanently joined within the holes, providing conductive paths. 4 figs.

Double sided circuit board and a method for its manufacture

DOEpatents

Lindenmeyer, Carl W.

1989-07-04

Conductance between the sides of a large double sided printed circuit board is provided using a method which eliminates the need for chemical immersion or photographic exposure of the entire large board. A plurality of through-holes are drilled or punched in a substratum according to the desired pattern, conductive laminae are made to adhere to both sides of the substratum covering the holes and the laminae are pressed together and permanently joined within the holes, providing conductive paths.

An advanced study on the hydrometallurgical processing of waste computer printed circuit boards to extract their valuable content of metals.

PubMed

Birloaga, Ionela; Coman, Vasile; Kopacek, Bernd; Vegliò, Francesco

2014-12-01

This study refers to two chemical leaching systems for the base and precious metals extraction from waste printed circuit boards (WPCBs); sulfuric acid with hydrogen peroxide have been used for the first group of metals, meantime thiourea with the ferric ion in sulfuric acid medium were employed for the second one. The cementation process with zinc, copper and iron metal powders was attempted for solutions purification. The effects of hydrogen peroxide volume in rapport with sulfuric acid concentration and temperature were evaluated for oxidative leaching process. 2M H2SO4 (98% w/v), 5% H2O2, 25 °C, 1/10 S/L ratio and 200 rpm were founded as optimal conditions for Cu extraction. Thiourea acid leaching process, performed on the solid filtrate obtained after three oxidative leaching steps, was carried out with 20 g/L of CS(NH2)2, 6g/L of Fe(3+), 0.5M H2SO4, The cross-leaching method was applied by reusing of thiourea liquid suspension and immersing 5 g/L of this reagent for each other experiment material of leaching. This procedure has lead to the doubling and, respectively, tripling, of gold and silver concentrations into solution. These results reveal a very efficient, promising and environmental friendly method for WPCBs processing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Transient digitizer with displacement current samplers

DOEpatents

McEwan, T.E.

1996-05-21

A low component count, high speed sample gate, and digitizer architecture using the sample gates is based on use of a signal transmission line, a strobe transmission line and a plurality of sample gates connected to the sample transmission line at a plurality of positions. The sample gates include a strobe pickoff structure near the strobe transmission line which generates a charge displacement current in response to propagation of the strobe signal on the strobe transmission line sufficient to trigger the sample gate. The sample gate comprises a two-diode sampling bridge and is connected to a meandered signal transmission line at one end and to a charge-holding cap at the other. The common cathodes are reverse biased. A voltage step is propagated down the strobe transmission line. As the step propagates past a capacitive pickoff, displacement current i=c(dv/dT), flows into the cathodes, driving the bridge into conduction and thereby charging the charge-holding capacitor to a value related to the signal. A charge amplifier converts the charge on the charge-holding capacitor to an output voltage. The sampler is mounted on a printed circuit board, and the sample transmission line and strobe transmission line comprise coplanar microstrips formed on a surface of the substrate. Also, the strobe pickoff structure may comprise a planar pad adjacent the strobe transmission line on the printed circuit board. 16 figs.

Transient digitizer with displacement current samplers

DOEpatents

McEwan, Thomas E.

1996-01-01

A low component count, high speed sample gate, and digitizer architecture using the sample gates is based on use of a signal transmission line, a strobe transmission line and a plurality of sample gates connected to the sample transmission line at a plurality of positions. The sample gates include a strobe pickoff structure near the strobe transmission line which generates a charge displacement current in response to propagation of the strobe signal on the strobe transmission line sufficient to trigger the sample gate. The sample gate comprises a two-diode sampling bridge and is connected to a meandered signal transmission line at one end and to a charge-holding cap at the other. The common cathodes are reverse biased. A voltage step is propagated down the strobe transmission line. As the step propagates past a capacitive pickoff, displacement current i=c(dv/dT), flows into the cathodes, driving the bridge into conduction and thereby charging the charge-holding capacitor to a value related to the signal. A charge amplifier converts the charge on the charge-holding capacitor to an output voltage. The sampler is mounted on a printed circuit board, and the sample transmission line and strobe transmission line comprise coplanar microstrips formed on a surface of the substrate. Also, the strobe pickoff structure may comprise a planar pad adjacent the strobe transmission line on the printed circuit board.

Printed Circuit Board Surface Finish and Effects of Chloride Contamination, Electric Field, and Humidity on Corrosion Reliability

NASA Astrophysics Data System (ADS)

Conseil-Gudla, Hélène; Jellesen, Morten S.; Ambat, Rajan

2017-02-01

Corrosion reliability is a serious issue today for electronic devices, components, and printed circuit boards (PCBs) due to factors such as miniaturization, globalized manufacturing practices which can lead to process-related residues, and global usage effects such as bias voltage and unpredictable user environments. The investigation reported in this paper focuses on understanding the synergistic effect of such parameters, namely contamination, humidity, PCB surface finish, pitch distance, and potential bias on leakage current under different humidity levels, and electrochemical migration probability under condensing conditions. Leakage currents were measured on interdigitated comb test patterns with three different types of surface finish typically used in the electronics industry, namely gold, copper, and tin. Susceptibility to electrochemical migration was studied under droplet conditions. The level of base leakage current (BLC) was similar for the different surface finishes and NaCl contamination levels up to relative humidity (RH) of 65%. A significant increase in leakage current was found for comb patterns contaminated with NaCl above 70% to 75% RH, close to the deliquescent RH of NaCl. Droplet tests on Cu comb patterns with varying pitch size showed that the initial BLC before dendrite formation increased with increasing NaCl contamination level, whereas electrochemical migration and the frequency of dendrite formation increased with bias voltage. The effect of different surface finishes on leakage current under humid conditions was not very prominent.

PHOTOCROSSLINKED IMMOBILIZATION OF POLYELECTROLYTES FOR TEMPLATE ASSISTED ENZYMATIC POLYMERIZATION OF CONJUGATED POLYMERS

EPA Science Inventory

Growing demand in consumer electronics raises need for efficient, affordable, environmentally benign and biodegradable substitutes for current technologies. Printed circuit boards contain heavy metals such as antimony, silver, chromium, zinc, lead, tin and copper. According t...

40 CFR 413.81 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Specialized definitions. 413.81 Section 413.81 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ELECTROPLATING POINT SOURCE CATEGORY Printed Circuit Board Subcategory § 413.81 Specialized...

Conductive elastomers by a new latex process

USDA-ARS?s Scientific Manuscript database

Electrically conductive polymers such as polyaniline can be used to in production of light-emitting diodes, printed circuit board components, antistatic materials, etc. Highly filled elastomers, such as those filled with metallic powders, can also conduct electricity. However, limitations due to co...

Nylon screws make inexpensive coil forms

NASA Technical Reports Server (NTRS)

Aucoin, G.; Rosenthal, C.

1978-01-01

Standard nylon screws act as coil form copper wire laid down in spiral thread. Completed coil may be bonded to printed-circuit board. However, it is impossible to tune coil by adjusting spacing between windings, technique sometimes used with air-core coils.

RECOVERY OF METAL USING ALUMINUM DISPLACEMENT

EPA Science Inventory

The removal of typical metals (Cu, Pb, Sn, Ni) from printed circuit and metal finishing waste streams was evaluated using displacement with aluminum. he metal is recovered as non-hazardous metal particles and can be recycled by smelting. n acceptable aluminum metal configuration ...

Ideas in Practice. Nuturing Creativity in a Measurements Course

ERIC Educational Resources Information Center

Neal, James P.

1972-01-01

Describes the conduct of a one-semester laboratory course for electrical engineering sophomores through the use of rack-mounted instruments and printed circuits. Concluded there was greater student and instructor interest and creativity in both lectures and laboratory. (CC)

AQUEOUS CLEANING OF PRINTED CIRCUIT BOARD STENCILS

EPA Science Inventory

The USEPA through NRMRL has partnered with the California Dept. of Toxic Substance Control under an ETV Pilot Project to verigy polllution prevention, recycling and waste treatment technologies. One of the projects selected for verification was the ultrasonic aqueous cleaning tec...

PILOT-SCALE STUDIES ON THE INCINERATION OF ELECTRONICS INDUSTRY WASTE

EPA Science Inventory

The paper describes experiments performed on a pilot-scale rotary kiln incinerator to investigate the emissions and operational behavior during the incineration of consumer electronics waste. These experiments were targeted at destroying the organic components of printed circuit ...

Metal Oxide Thin Film Transistors on Paper Substrate: Fabrication, Characterization, and Printing Process

NASA Astrophysics Data System (ADS)

Choi, Nack-Bong

Flexible electronics is an emerging next-generation technology that offers many advantages such as light weight, durability, comfort, and flexibility. These unique features enable many new applications such as flexible display, flexible sensors, conformable electronics, and so forth. For decades, a variety of flexible substrates have been demonstrated for the application of flexible electronics. Most of them are plastic films and metal foils so far. For the fundamental device of flexible circuits, thin film transistors (TFTs) using poly silicon, amorphous silicon, metal oxide and organic semiconductor have been successfully demonstrated. Depending on application, low-cost and disposable flexible electronics will be required for convenience. Therefore it is important to study inexpensive substrates and to explore simple processes such as printing technology. In this thesis, paper is introduced as a new possible substrate for flexible electronics due to its low-cost and renewable property, and amorphous indium gallium zinc oxide (a-IGZO) TFTs are realized as the promising device on the paper substrate. The fabrication process and characterization of a-IGZO TFT on the paper substrate are discussed. a-IGZO TFTs using a polymer gate dielectric on the paper substrate demonstrate excellent performances with field effect mobility of ˜20 cm2 V-1 s-1, on/off current ratio of ˜106, and low leakage current, which show the enormous potential for flexible electronics application. In order to complement the n-channel a-IGZO TFTs and then enable complementary metal-oxide semiconductor (CMOS) circuit architectures, cuprous oxide is studied as a candidate material of p-channel oxide TFTs. In this thesis, a printing process is investigated as an alternative method for the fabrication of low-cost and disposable electronics. Among several printing methods, a modified offset roll printing that prints high resolution patterns is presented. A new method to fabricate a high resolution printing plate is investigated and the most favorable condition to transfer ink from a blanket to a cliche is studied. Consequently, a high resolution cliche is demonstrated and the printed patterns of 10mum width and 6mum line spacing are presented. In addition, the top gate a-IGZO TFTs with channel width/length of 12/6mum is successfully demonstrated by printing etch-resists. This work validates the compatibility of a-IGZO TFT on paper substrate for the disposable microelectronics application and presents the potential of low-cost and high resolution printing technology.

Cables and crosstalk

NASA Astrophysics Data System (ADS)

Paul, Clayton R.

1991-06-01

Crosstalk is the unintentional electromagnetic coupling between circuits which are connected by parallel conductors that lie in close proximity to each other. Some examples are wires in cable harnesses or metallic lands on printed-circuit boards (PCB's). This unintended interaction between two or more circuits via their electromagnetic fields can cause interference problems. Signals from one circuit that couple to another circuit appear at the terminals of the devices that are interconnected by the wires. If these signals are of sufficient magnitude or spectral content, they may cause unintended operation of the device or a degradation in its performance. A summary of the standard models used for predicting crosstalk in various types of configurations is presented. The discussion focusses on the relative accuracies, regions of applicability, and computational complexity of the models. A simple explanation of the ability (or inability) of shielded wires and twisted pairs of wires to reduce the crosstalk is also given.

Three-dimensional paper-based electrochemiluminescence immunodevice for multiplexed measurement of biomarkers and point-of-care testing.

PubMed

Ge, Lei; Yan, Jixian; Song, Xianrang; Yan, Mei; Ge, Shenguang; Yu, Jinghua

2012-02-01

In this work, electrochemiluminescence (ECL) immunoassay was introduced into the recently proposed microfluidic paper-based analytical device (μPADs) based on directly screen-printed electrodes on paper for the very first time. The screen-printed paper-electrodes will be more important for further development of this paper-based ECL device in simple, low-cost and disposable application than commercialized ones. To further perform high-performance, high-throughput, simple and inexpensive ECL immunoassay on μPAD for point-of-care testing, a wax-patterned three-dimensional (3D) paper-based ECL device was demonstrated for the very first time. In this 3D paper-based ECL device, eight carbon working electrodes including their conductive pads were screen-printed on a piece of square paper and shared the same Ag/AgCl reference and carbon counter electrodes on another piece of square paper after stacking. Using typical tris-(bipyridine)-ruthenium (Ⅱ) - tri-n-propylamine ECL system, the application test of this 3D paper-based ECL device was performed through the diagnosis of four tumor markers in real clinical serum samples. With the aid of a facile device-holder and a section-switch assembled on the analyzer, eight working electrodes were sequentially placed into the circuit to trigger the ECL reaction in the sweeping range from 0.5 to 1.1 V at room temperature. In addition, this 3D paper-based ECL device can be easily integrated and combined with the recently emerging paper electronics to further develop simple, sensitive, low-cost, disposable and portable μPAD for point-of-care testing, public health and environmental monitoring in remote regions, developing or developed countries. Copyright © 2011 Elsevier Ltd. All rights reserved.

Recovery of materials from waste printed circuit boards by vacuum pyrolysis and vacuum centrifugal separation.

PubMed

Zhou, Yihui; Wu, Wenbiao; Qiu, Keqiang

2010-11-01

In this research, a two-step process consisting of vacuum pyrolysis and vacuum centrifugal separation was employed to treat waste printed circuit boards (WPCBs). Firstly, WPCBs were pyrolysed under vacuum condition at 600 °C for 30 min in a lab-scale reactor. Then, the obtained pyrolysis residue was heated under vacuum until the solder was melted, and then the molten solder was separated from the pyrolysis residue by the centrifugal force. The results of vacuum pyrolysis showed that the type-A of WPCBs (the base plates of which was made from cellulose paper reinforced phenolic resin) pyrolysed to form an average of 67.97 wt.% residue, 27.73 wt.% oil, and 4.30 wt.% gas; and pyrolysis of the type-B of WPCBs (the base plates of which was made from glass fiber reinforced epoxy resin) led to an average mass balance of 72.20 wt.% residue, 21.45 wt.% oil, and 6.35 wt.% gas. The results of vacuum centrifugal separation showed that the separation of solder was complete when the pyrolysis residue was heated at 400 °C, and the rotating drum was rotated at 1200 rpm for 10 min. The pyrolysis oil and gas can be used as fuel or chemical feedstock after treatment. The pyrolysis residue after solder separation contained various metals, glass fibers and other inorganic materials, which could be recycled for further processing. The recovered solder can be reused directly and it can also be a good resource of lead and tin for refining. Copyright © 2010 Elsevier Ltd. All rights reserved.

A Real Time Controller For Applications In Smart Structures

NASA Astrophysics Data System (ADS)

Ahrens, Christian P.; Claus, Richard O.

1990-02-01

Research in smart structures, especially the area of vibration suppression, has warranted the investigation of advanced computing environments. Real time PC computing power has limited development of high order control algorithms. This paper presents a simple Real Time Embedded Control System (RTECS) in an application of Intelligent Structure Monitoring by way of modal domain sensing for vibration control. It is compared to a PC AT based system for overall functionality and speed. The system employs a novel Reduced Instruction Set Computer (RISC) microcontroller capable of 15 million instructions per second (MIPS) continuous performance and burst rates of 40 MIPS. Advanced Complimentary Metal Oxide Semiconductor (CMOS) circuits are integrated on a single 100 mm by 160 mm printed circuit board requiring only 1 Watt of power. An operating system written in Forth provides high speed operation and short development cycles. The system allows for implementation of Input/Output (I/O) intensive algorithms and provides capability for advanced system development.

Subwavelength wave manipulation in a thin surface-wave bandgap crystal.

PubMed

Gao, Zhen; Wang, Zhuoyuan; Zhang, Baile

2018-01-01

It has been recently reported that the unit cell of wire media metamaterials can be tailored locally to shape the flow of electromagnetic waves at deep-subwavelength scales [Nat. Phys.9, 55 (2013)NPAHAX1745-247310.1038/nphys2480]. However, such bulk structures have a thickness of at least the order of wavelength, thus hindering their applications in the on-chip compact plasmonic integrated circuits. Here, based upon a Sievenpiper "mushroom" array [IEEE Trans. Microwave Theory Tech.47, 2059 (1999)IETMAB0018-948010.1109/22.798001], which is compatible with standard printed circuit board technology, we propose and experimentally demonstrate the subwavelength manipulation of surface waves on a thin surface-wave bandgap crystal with a thickness much smaller than the wavelength (1/30th of the operating wavelength). Functional devices including a T-shaped splitter and sharp bend are constructed with good performance.

Ink jet printing of silver metallization for photovoltaics

NASA Technical Reports Server (NTRS)

Vest, R. W.

1985-01-01

Progress was made in the continuing development of the ink jet printing system for thick film circuits. The unit being used is a prototype ink jet printer. One of the first tasks completed was the complete documentation of this ink jet printing system as it existed. It was determined that this was an essential step in deciding what modifications were needed to the system and how these modifications would be implemented. Design modification studies were started for electronic, mechanical, and programming aspects of the ystem. The areas needeing improvement were discussed and applicable changes decided upon. Some improvments were completed. Although the general areas needing improving were identified and some changes decided upon, the exact details of how other changes can be implemented are yet been decided.

Method of forming electronically conducting polymers on conducting and nonconducting substrates

NASA Technical Reports Server (NTRS)

Hodko, Dalibor (Inventor); Clarke, Eric T. (Inventor); Miller, David L. (Inventor); Murphy, Oliver J. (Inventor); Hitchens, G. Duncan (Inventor); Parker, Donald L. (Inventor)

2001-01-01

The present invention provides electronically conducting polymer films formed from photosensitive formulations of pyrrole and an electron acceptor that have been selectively exposed to UV light, laser light, or electron beams. The formulations may include photoinitiators, flexibilizers, solvents and the like. These solutions can be used in applications including printed circuit boards and through-hole plating and enable direct metallization processes on non-conducting substrates. After forming the conductive polymer patterns, a printed wiring board can be formed by sensitizing the polymer with palladium and electrolytically depositing copper.

The Production of Printed Circuit Boards, Photo-Anodised and Screen Printed Instrument Panels.

DTIC Science & Technology

1981-01-01

Laboratories, Melbourne 12. RELEASE LIMITATIONS (of the document): Approved for Public Release. 12.0. OVERSEAS: N.0.1 I P.R. 1 A I I B I I C I D EI 13...solutions. 5.1 baths Required (N.B. Tanks shoula be of rigid P.V.C.) 1. Amonium persulphate solution 100 gm/L. 2. Sulphuric acid 10% (A.R. GRADE...120 degrees C for at least 10 mins. Etchant 1: 55% weight/volume solution of ferric nitrate used at 49 degrees C. This solution is made by adding

CARBON BLACK DISPERSION PRE-PLATING TECHNOLOGY FOR PRINTED WIRE BOARD MANUFACTURING

EPA Science Inventory

This evaluation addresses the product quality, waste reduction, and economic issues involved in replacing electroless copper with a carbon black dispersion technology. McCurdy Circuits of Orange County, California, currently has both processes in operation. McCurdy has found that...

PILOT-SCALE EVALUATION OF THE IRON-ENHANCED DECHLORINATION TECHNOLOGY FOR REMEDIATION OF CONTAMINATED GROUNDWATER

EPA Science Inventory

An iron-enhanced dechlorination technology was evaluated, under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) program, at a contaminated printed circuit board manufacturing site in New Jersey. This paper describes the feasibility...

The Chemistry of Everyday.

ERIC Educational Resources Information Center

Journal of Chemical Education, 1983

1983-01-01

Thirteen papers presented at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982) are summarized. A variety of chemical topics were addressed, including development of printed circuit boards, chemical/physical structure of hair, brewing, uses of EDTA, cleaning agents, hydrocyanation of olefins, drag reducers, and…

Life Cycle Analysis of a SpaceCube Printed Circuit Board Assembly Using Physics of Failure Methodologies

NASA Technical Reports Server (NTRS)

Sood, Bhanu; Evans, John; Daniluk, Kelly; Sturgis, Jason; Davis, Milton; Petrick, David

2017-01-01

In this reliability life cycle evaluation of the SpaceCube 2.0 processor card, a partially populated version of the card is being evaluated to determine its durability with respect to typical GSFC mission loads.

Hazardous Waste Cleanup: General Electric – Main Plant Site in Schenectady, New York

EPA Pesticide Factsheets

GE purchased the property at Genesee Street in 1951 and constructed a manufacturing plant that produced a variety of electrical components including radar equipment, printed circuit boards and high voltage semiconductors. In January 1986, Powerex, Inc., ac

Materials Integration and Doping of Carbon Nanotube-based Logic Circuits

NASA Astrophysics Data System (ADS)

Geier, Michael

Over the last 20 years, extensive research into the structure and properties of single- walled carbon nanotube (SWCNT) has elucidated many of the exceptional qualities possessed by SWCNTs, including record-setting tensile strength, excellent chemical stability, distinctive optoelectronic features, and outstanding electronic transport characteristics. In order to exploit these remarkable qualities, many application-specific hurdles must be overcome before the material can be implemented in commercial products. For electronic applications, recent advances in sorting SWCNTs by electronic type have enabled significant progress towards SWCNT-based integrated circuits. Despite these advances, demonstrations of SWCNT-based devices with suitable characteristics for large-scale integrated circuits have been limited. The processing methodologies, materials integration, and mechanistic understanding of electronic properties developed in this dissertation have enabled unprecedented scales of SWCNT-based transistor fabrication and integrated circuit demonstrations. Innovative materials selection and processing methods are at the core of this work and these advances have led to transistors with the necessary transport properties required for modern circuit integration. First, extensive collaborations with other research groups allowed for the exploration of SWCNT thin-film transistors (TFTs) using a wide variety of materials and processing methods such as new dielectric materials, hybrid semiconductor materials systems, and solution-based printing of SWCNT TFTs. These materials were integrated into circuit demonstrations such as NOR and NAND logic gates, voltage-controlled ring oscillators, and D-flip-flops using both rigid and flexible substrates. This dissertation explores strategies for implementing complementary SWCNT-based circuits, which were developed by using local metal gate structures that achieve enhancement-mode p-type and n-type SWCNT TFTs with widely separated and symmetric threshold voltages. Additionally, a novel n-type doping procedure for SWCNT TFTs was also developed utilizing a solution-processed organometallic small molecule to demonstrate the first network top-gated n-type SWCNT TFTs. Lastly, new doping and encapsulation layers were incorporated to stabilize both p-type and n-type SWCNT TFT electronic properties, which enabled the fabrication of large-scale memory circuits. Employing these materials and processing advances has addressed many application specific barriers to commercialization. For instance, the first thin-film SWCNT complementary metal-oxide-semi-conductor (CMOS) logic devices are demonstrated with sub-nanowatt static power consumption and full rail-to-rail voltage transfer characteristics. With the introduction of a new n-type Rh-based molecular dopant, the first SWCNT TFTs are fabricated in top-gate geometries over large areas with high yield. Then by utilizing robust encapsulation methods, stable and uniform electronic performance of both p-type and n-type SWCNT TFTs has been achieved. Based on these complementary SWCNT TFTs, it is possible to simulate, design, and fabricate arrays of low-power static random access memory (SRAM) circuits, achieving large-scale integration for the first time based on solution-processed semiconductors. Together, this work provides a direct pathway for solution processable, large scale, power-efficient advanced integrated logic circuits and systems.

Fully Printed Flexible and Stretchable Electronics

NASA Astrophysics Data System (ADS)

Zhang, Suoming

Through this thesis proposal, the author has demonstrated series of flexible or stretchable sensors including strain gauge, pressure sensors, display arrays, thin film transistors and photodetectors fabricated by a direct printing process. By adopting the novel serpentine configuration with conventional non-stretchable materials silver nanoparticles, the fully printed stretchable devices are successfully fabricated on elastomeric substrate with the demonstration of stretchable conductors that can maintain the electrical properties under strain and the strain gauge, which could be used to measure the strain in desired locations and also to monitor individual person's finger motion. And by investigating the intrinsic stretchable materials silver nanowires (AgNWs) with the conventional configuration, the fully printed stretchable conductors are achieved on various substrates including Si, glass, Polyimide, Polydimethylsiloxane (PDMS) and Very High Bond (VHB) tape with the illustration of the capacitive pressure sensor and stretchable electroluminescent displays. In addition, intrinsically stretchable thin-film transistors (TFTs) and integrated logic circuits are directly printed on elastomeric PDMS substrates. The printed devices utilize carbon nanotubes and a type of hybrid gate dielectric comprising PDMS and barium titanate (BaTiO3) nanoparticles. The BaTiO3/PDMS composite simultaneously provides high dielectric constant, superior stretchability, low leakage, as well as good printability and compatibility with the elastomeric substrate. Both TFTs and logic circuits can be stretched beyond 50% strain along either channel length or channel width directions for thousands of cycles while showing no significant degradation in electrical performance. Finally, by applying the SWNTs as the channel layer of the thin film transistor, we successfully fabricate the fully printed flexible photodetector which exhibits good electrical characteristics and the transistors exhibit good reliability under bending conditions owing to the ultrathin polyimide substrate as well as the superior mechanical flexibility of the gate dielectric and carbon nanotube network. Furthermore, we have demonstrated that by using two types of SWCNT samples with different optical absorption characteristics, the photoresponse exhibits unique wavelength selectivity, as manifested by the good correlation between the responsive wavelengths of the devices with the absorption peaks of the corresponding carbon nanotubes. All the proposed materials above together with the unique direct printing process may offer an entry into more sophisticated flexible or stretchable electronic systems with monolithically integrated sensors, actuators, and displays for real life applications.

Evaluation of hybrid polymers for high-precision manufacturing of 3D optical interconnects by two-photon absorption lithography

NASA Astrophysics Data System (ADS)

Schleunitz, A.; Klein, J. J.; Krupp, A.; Stender, B.; Houbertz, R.; Gruetzner, G.

2017-02-01

The fabrication of optical interconnects has been widely investigated for the generation of optical circuit boards. Twophoton absorption (TPA) lithography (or high-precision 3D printing) as an innovative production method for direct manufacture of individual 3D photonic structures gains more and more attention when optical polymers are employed. In this regard, we have evaluated novel ORMOCER-based hybrid polymers tailored for the manufacture of optical waveguides by means of high-precision 3D printing. In order to facilitate future industrial implementation, the processability was evaluated and the optical performance of embedded waveguides was assessed. The results illustrate that hybrid polymers are not only viable consumables for industrial manufacture of polymeric micro-optics using generic processes such as UV molding. They also are potential candidates to fabricate optical waveguide systems down to the chip level where TPA-based emerging manufacturing techniques are engaged. Hence, it is shown that hybrid polymers continue to meet the increasing expectations of dynamically growing markets of micro-optics and optical interconnects due to the flexibility of the employed polymer material concept.

3D Printed "Earable" Smart Devices for Real-Time Detection of Core Body Temperature.

PubMed

Ota, Hiroki; Chao, Minghan; Gao, Yuji; Wu, Eric; Tai, Li-Chia; Chen, Kevin; Matsuoka, Yasutomo; Iwai, Kosuke; Fahad, Hossain M; Gao, Wei; Nyein, Hnin Yin Yin; Lin, Liwei; Javey, Ali

2017-07-28

Real-time detection of basic physiological parameters such as blood pressure and heart rate is an important target in wearable smart devices for healthcare. Among these, the core body temperature is one of the most important basic medical indicators of fever, insomnia, fatigue, metabolic functionality, and depression. However, traditional wearable temperature sensors are based upon the measurement of skin temperature, which can vary dramatically from the true core body temperature. Here, we demonstrate a three-dimensional (3D) printed wearable "earable" smart device that is designed to be worn on the ear to track core body temperature from the tympanic membrane (i.e., ear drum) based on an infrared sensor. The device is fully integrated with data processing circuits and a wireless module for standalone functionality. Using this smart earable device, we demonstrate that the core body temperature can be accurately monitored regardless of the environment and activity of the user. In addition, a microphone and actuator are also integrated so that the device can also function as a bone conduction hearing aid. Using 3D printing as the fabrication method enables the device to be customized for the wearer for more personalized healthcare. This smart device provides an important advance in realizing personalized health care by enabling real-time monitoring of one of the most important medical parameters, core body temperature, employed in preliminary medical screening tests.

Computer simulation of the pneumatic separator in the pneumatic-electrostatic separation system for recycling waste printed circuit boards with electronic components.

PubMed

Xue, Mianqiang; Xu, Zhenming

2013-05-07

Technologies could be integrated in different ways into automatic recycling lines for a certain kind of electronic waste according to practical requirements. In this study, a new kind of pneumatic separator with openings at the dust hooper was applied combing with electrostatic separation for recycling waste printed circuit boards. However, the flow pattern and the particles' movement behavior could not be obtained by experimental methods. To better control the separation quantity and the material size distribution, computational fluid dynamics was used to model the new pneumatic separator giving a detailed understanding of the mechanisms. Simulated results showed that the tangential velocity direction reversed with a relatively small value. Axial velocity exhibited two sharp decreases at the x axis. It is indicated that the bottom openings at the dust hopper resulted in an enormous change in the velocity profile. A new phenomenon that was named dusting was observed, which would mitigate the effect of particles with small diameter on the following electrostatic separation and avoid materials plugging caused by the waste printed circuit boards special properties effectively. The trapped materials were divided into seven grades. Experimental results showed that the mass fraction of grade 5, grade 6, and grade 7 materials were 27.54%, 15.23%, and 17.38%, respectively. Grade 1 particles' mass fraction was reduced by 80.30% compared with a traditional separator. Furthermore, the monocrystalline silicon content in silicon element in particles with a diameter of -0.091 mm was 18.9%, higher than that in the mixed materials. This study could serve as guidance for the future material flow control, automation control, waste recycling, and semiconductor storage medium destruction.

The major components of particles emitted during recycling of waste printed circuit boards in a typical e-waste workshop of South China

NASA Astrophysics Data System (ADS)

Bi, Xinhui; Simoneit, Bernd R. T.; Wang, ZhenZhen; Wang, Xinming; Sheng, Guoying; Fu, Jiamo

2010-11-01

Electronic waste from across the world is dismantled and disposed of in China. The low-tech recycling methods have caused severe air pollution. Air particle samples from a typical workshop of South China engaged in recycling waste printed circuit boards have been analyzed with respect to chemical constituents. This is the first report on the chemical composition of particulate matter (PM) emitted in an e-waste recycling workshop of South China. The results show that the composition of PM from this recycling process was totally different from other emission sources. Organic matter comprised 46.7-51.6% of the PM. The major organic constituents were organophosphates consisting mainly of triphenyl phosphate (TPP) and its methyl substituted compounds, methyl esters of hexadecanoic and octadecanoic acids, levoglucosan and bisphenol A. TPP and bisphenol A were present at 1-5 orders of magnitude higher than in other indoor and outdoor environments throughout the world, which implies that they might be used as potential markers for e-waste recycling. The elemental carbon, inorganic elements and ions had a minor contribution to the PM (<5% each). The inorganic elements were dominated by phosphorus and followed by crustal elements and metal elements Pb, Zn, Sn, and lesser Cu, Sb, Mn, Ni, Ba and Cd. The recycling of printed circuit boards was demonstrated as an important contributor of heavy metal contamination, particularly Cd, Pb and Ni, to the local environment. These findings suggest that this recycling method represents a strong source of PM associated with pollutants to the ambient atmosphere of an e-waste recycling locale.

Improved mask-based CD uniformity for gridded-design-rule lithography

NASA Astrophysics Data System (ADS)

Faivishevsky, Lev; Khristo, Sergey; Sagiv, Amir; Mangan, Shmoolik

2009-03-01

The difficulties encountered during lithography of state-of-the-art 2D patterns are formidable, and originate from the fact that deep sub-wavelength features are being printed. This results in a practical limit of k1 >=0.4 as well as a multitude of complex restrictive design rules, in order to mitigate or minimize lithographic hot spots. An alternative approach, that is gradually attracting the lithographic community's attention, restricts the design of critical layers to straight, dense lines (a 1D grid), that can be relatively easily printed using current lithographic technology. This is then followed by subsequent, less critical trimming stages to obtain circuit functionality. Thus, the 1D gridded approach allows hotspot-free, proximity-effect free lithography of ultra low- k1 features. These advantages must be supported by a stable CD control mechanism. One of the overriding parameters impacting CDU performance is photo mask quality. Previous publications have demonstrated that IntenCDTM - a novel, mask-based CDU mapping technology running on Applied Materials' Aera2TM aerial imaging mask inspection tool - is ideally fit for detecting mask-based CDU issues in 1D (L&S) patterned masks for memory production. Owing to the aerial nature of image formation, IntenCD directly probes the CD as it is printed on the wafer. In this paper we suggest that IntenCD is naturally fit for detecting mask-based CDU issues in 1D GDR masks. We then study a novel method of recovering and quantifying the physical source of printed CDU, using a novel implementation of the IntenCD technology. We demonstrate that additional, simple measurements, which can be readily performed on board the Aera2TM platform with minimal throughput penalty, may complement IntenCD and allow a robust estimation of the specific nature and strength of mask error source, such as pattern width variation or phase variation, which leads to CDU issues on the printed wafer. We finally discuss the roles played by IntenCD in advanced GDR mask production, starting with tight control over mask production process, continuing to mask qualification at mask shop and ending at in-line wafer CDU correction in fabs.

5 CFR 532.267 - Special wage schedules for aircraft, electronic, and optical instrument overhaul and repair...

Code of Federal Regulations, 2014 CFR

2014-01-01

... Photographic and photocopying equipment manufacturing. 3341 Computer and peripheral equipment manufacturing. 33422 Radio and television broadcasting and wireless communications equipment manufacturing. 33429 Other communications equipment manufacturing. 3343 Audio and video equipment manufacturing. 334412 Bare printed circuit...

Adaptive Changes in Grain-Size in Morphological Processing

ERIC Educational Resources Information Center

Lee, Chang H.

2008-01-01

Substantial neurobiological data indicate that the dominant cortical region for printed-word recognition shifts from a temporo-parietal (dorsal) to an occipito-temporal (ventral) locus with increasing recognition experience. The circuits also have different characteristic speeds of response and word preferences. Previous evidence suggested that…

76 FR 70760 - Nexergy, Inc., Including On-Site Leased Workers From Act-I Staffing, Kelly Services and Snider...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-15

... engaged in activities related to the production of battery packs, printed circuit boards and wire harnesses. The notice was published in the Federal Register on July 8, 2011 (76 FR 40401). At the request of...

Manufacturing Methods and Technology for Digital Fault Isolation for Printed Circuit Boards.

DTIC Science & Technology

1979-08-25

microprocessors and support chips, ROMs, RAMs, UARTs , etc. They also include rules for busses and memory testing. The special rules for test points emphasize...I 8). UART .. ...................................................... I 9). SAT...0.0 I ( 8). UART ...................................................... 0.0O S 9). SAT

Printed Circuit Board Quality Assurance

NASA Technical Reports Server (NTRS)

Sood, Bhanu

2016-01-01

PCB Assurance Summary: PCB assurance actives are informed by risk in context of the Project. Lessons are being applied across Projects for continuous improvements. Newer component technologies, smaller/high pitch devices: tighter and more demanding PCB designs: Identifying new research areas. New materials, designs, structures and test methods.

Leaching of metals from large pieces of printed circuit boards using citric acid and hydrogen peroxide.

PubMed

Jadhav, Umesh; Su, C; Hocheng, Hong

2016-12-01

In the present study, the leaching of metals from large pieces of computer printed circuit boards (CPCBs) was studied. A combination of citric acid (0.5 M) and 1.76 M hydrogen peroxide (H 2 O 2 ) was used to leach the metals from CPCB piece. The influence of system variables such as H 2 O 2 concentration, concentration of citric acid, shaking speed, and temperature on the metal leaching process was investigated. The complete metal leaching was achieved in 4 h from a 4 × 4 cm CPCB piece. The presence of citric acid and H 2 O 2 together in the leaching solution is essential for complete metal leaching. The optimum addition amount of H 2 O 2 was 5.83 %. The citric acid concentration and shaking speed had an insignificant effect on the leaching of metals. The increase in the temperature above 30 °C showed a drastic effect on metal leaching process.

The Infrared Automatic Mass Screening (IRAMS) System For Printed Circuit Board Fault Detection

NASA Astrophysics Data System (ADS)

Hugo, Perry W.

1987-05-01

Office of the Program Manager for TMDE (OPM TMDE) has initiated a program to develop techniques for evaluating the performance of printed circuit boards (PCB's) using infrared thermal imaging. It is OPM TMDE's expectation that the standard thermal profile (STP) will become the basis for the future rapid automatic detection and isolation of gross failure mechanisms on units under test (UUT's). To accomplish this OPM TMDE has purchased two Infrared Automatic Mass Screening ( I RAMS) systems which are scheduled for delivery in 1987. The IRAMS system combines a high resolution infrared thermal imager with a test bench and diagnostic computer hardware and software. Its purpose is to rapidly and automatically compare the thermal profiles of a UUT with the STP of that unit, recalled from memory, in order to detect thermally responsive failure mechanisms in PCB's. This paper will review the IRAMS performance requirements, outline the plan for implementing the two systems and report on progress to date.

Performance of the electrical generator cell by the ferrous alloys of printed circuit board scrap and Iron Metal 1020

NASA Astrophysics Data System (ADS)

Sahan, Y.; Sudarsono, S.; Silviana, E.; Chairul; Wisrayetti

2018-04-01

Galvani cell is one of thealternative energy. This cell can be used as an electric resources. In this research, the generator cell was designed and builds to generate the electric. The generator cell consisted of the iron metal 1020 were used as anode, the ferrous alloys of printed circuit board scrapwas then used as chatode, and NaCl solution as an electrolyte. The aim of this research is to estimate the performance of this generator cell by using variation of NaCl concentration (i.e. 1%, 3%, 5%, 7%, and 9%) with the electrodes pair ( 1 and 8 pairs). The performance of the cell was measured with a multi tester equipment and a LED bulb (5-watt 3Volt). The Results shown that the generator cell can produce the electric power of 3.679 Volt maximally by using NaCl 9% and 8 electrode pairs applied for this condition.

Electrostatic separation for recovering metals and nonmetals from waste printed circuit board: problems and improvements.

PubMed

Wu, Jiang; Li, Jia; Xu, Zhenming

2008-07-15

Electrostatic separation is an effective and environmentally friendly method for recycling comminuted waste printed circuit boards (PCB). As a classical separator, the roll-type corona-electrostatic separator (RTS) has some advantages in this field. However, there are still some notable problems, such as the middling products and their further treatment, impurity of nonconductive products because of the aggregation of fine particles, and stability of the separation process and balance between the production capacity and the separation quality. To overcome these problems, a conception of two-step separation is presented, and a new two-roll type corona-electrostatic separator (T-RTS) was built As compared to RTS, the conductive products increase by 8.9%, the middling products decrease by 45%, and the production capacity increases by 50% in treating comminuted PCB wastes by T-RTS. In addition, the separation process in T-RTS is more stable. Therefore, T-RTS is a promising separator for recycling comminuted PCB.

Electrostatic separation for recycling waste printed circuit board: a study on external factor and a robust design for optimization.

PubMed

Hou, Shibing; Wu, Jiang; Qin, Yufei; Xu, Zhenming

2010-07-01

Electrostatic separation is an effective and environmentally friendly method for recycling waste printed circuit board (PCB) by several kinds of electrostatic separators. However, some notable problems have been detected in its applications and cannot be efficiently resolved by optimizing the separation process. Instead of the separator itself, these problems are mainly caused by some external factors such as the nonconductive powder (NP) and the superficial moisture of feeding granule mixture. These problems finally lead to an inefficient separation. In the present research, the impacts of these external factors were investigated and a robust design was built to optimize the process and to weaken the adverse impact. A most robust parameter setting (25 kv, 80 rpm) was concluded from the experimental design. In addition, some theoretical methods, including cyclone separation, were presented to eliminate these problems substantially. This will contribute to efficient electrostatic separation of waste PCB and make remarkable progress for industrial applications.

Impact of nonconductive powder on electrostatic separation for recycling crushed waste printed circuit board.

PubMed

Wu, Jiang; Qin, Yufei; Zhou, Quan; Xu, Zhenming

2009-05-30

The electrostatic separation is an effective and environmentally friendly method for recycling metals and nonmetals from crushed printed circuit board (PCB) wastes. However, it still confronts some problems brought by nonconductive powder (NP). Firstly, the NP is fine and liable to aggregate. This leads to an increase of middling products and loss of metals. Secondly, the stability of separation process is influenced by NP. Finally, some NPs accumulate on the surface of the corona and electrostatic electrodes during the process. These problems lead to an inefficient separation. In the present research, the impacts of NP on electrostatic separation are investigated. The experimental results show that: the separation is notably influenced when the NP content is more than 10%. With the increase of NP content, the middling products sharply increase from 1.4 g to 4.3g (increase 207.1%), while the conductive products decrease from 24.0 g to 19.1g (decrease 20.4%), and the separation process become more instable.

Hydrometallurgical Recovery of Metals from Large Printed Circuit Board Pieces.

PubMed

Jadhav, U; Hocheng, H

2015-09-29

The recovery of precious metals from waste printed circuit boards (PCBs) is an effective recycling process. This paper presents a promising hydrometallurgical process to recover precious metals from waste PCBs. To simplify the metal leaching process, large pieces of PCBs were used instead of a pulverized sample. The chemical coating present on the PCBs was removed by sodium hydroxide (NaOH) treatment prior to the hydrometallurgical treatment. Among the leaching reagents examined, hydrochloric acid (HCl) showed great potential for the recovery of metals. The HCl-mediated leaching of waste PCBs was investigated over a range of conditions. Increasing the acid concentration decreased the time required for complete metal recovery. The shaking speed showed a pronounced positive effect on metal recovery, but the temperature showed an insignificant effect. The results showed that 1 M HCl recovered all of the metals from 4 cm × 4 cm PCBs at room temperature and 150 rpm shaking speed in 22 h.

Theoretic model and computer simulation of separating mixture metal particles from waste printed circuit board by electrostatic separator.

PubMed

Li, Jia; Xu, Zhenming; Zhou, Yaohe

2008-05-30

Traditionally, the mixture metals from waste printed circuit board (PCB) were sent to the smelt factory to refine pure copper. Some valuable metals (aluminum, zinc and tin) with low content in PCB were lost during smelt. A new method which used roll-type electrostatic separator (RES) to recovery low content metals in waste PCB was presented in this study. The theoretic model which was established from computing electric field and the analysis of forces on the particles was used to write a program by MATLAB language. The program was design to simulate the process of separating mixture metal particles. Electrical, material and mechanical factors were analyzed to optimize the operating parameters of separator. The experiment results of separating copper and aluminum particles by RES had a good agreement with computer simulation results. The model could be used to simulate separating other metal (tin, zinc, etc.) particles during the process of recycling waste PCBs by RES.

Hydrometallurgical Recovery of Metals from Large Printed Circuit Board Pieces

PubMed Central

Jadhav, U.; Hocheng, H.

2015-01-01

The recovery of precious metals from waste printed circuit boards (PCBs) is an effective recycling process. This paper presents a promising hydrometallurgical process to recover precious metals from waste PCBs. To simplify the metal leaching process, large pieces of PCBs were used instead of a pulverized sample. The chemical coating present on the PCBs was removed by sodium hydroxide (NaOH) treatment prior to the hydrometallurgical treatment. Among the leaching reagents examined, hydrochloric acid (HCl) showed great potential for the recovery of metals. The HCl-mediated leaching of waste PCBs was investigated over a range of conditions. Increasing the acid concentration decreased the time required for complete metal recovery. The shaking speed showed a pronounced positive effect on metal recovery, but the temperature showed an insignificant effect. The results showed that 1 M HCl recovered all of the metals from 4 cm × 4 cm PCBs at room temperature and 150 rpm shaking speed in 22 h. PMID:26415827

Thiourea leaching gold and silver from the printed circuit boards of waste mobile phones.

PubMed

Jing-ying, Li; Xiu-li, Xu; Wen-quan, Liu

2012-06-01

The present communication deals with the leaching of gold and silver from the printed circuit boards (PCBs) of waste mobile phones using an effective and less hazardous system, i.e., a thiourea leaching process as an alternative to the conventional and toxic cyanide leaching of gold. The influence of particle size, thiourea and Fe(3+) concentrations and temperature on the leaching of gold and silver from waste mobile phones was investigated. Gold extraction was found to be enhanced in a PCBs particle size of 100 mesh with the solutions containing 24 g/L thiourea and Fe(3+) concentration of 0.6% under the room temperature. In this case, about 90% of gold and 50% of silver were leached by the reaction of 2h. The obtained data will be useful for the development of processes for the recycling of gold and silver from the PCBs of waste mobile phones. Copyright © 2012 Elsevier Ltd. All rights reserved.

Recovery of high purity precious metals from printed circuit boards.

PubMed

Park, Young Jun; Fray, Derek J

2009-05-30

Waste printed circuit boards (WPCB) have an inherent value because of the precious metal content. For an effective recycling of WPCB, it is essential to recover the precious metals. This paper reports a promising method to recover the precious metals. Aqua regia was used as a leachant and the ratio between metals and leachant was fixed at 1/20 (g/ml). Silver is relatively stable so the amount of about 98 wt.% of the input was recovered without an additional treatment. Palladium formed a red precipitate during dissolution, which were consisted of Pd(NH(4))(2)Cl(6). The amount precipitated was 93 wt.% of the input palladium. A liquid-liquid extraction with toluene was used to extract gold selectively. Also, dodecanethiol and sodium borohydride solution were added to make gold nanoparticles. Gold of about 97 wt.% of the input was recovered as nanoparticles which was identified with a high-resolution transmission electron microscopy through selected area electron diffraction and nearest-neighbor lattice spacing.

Adsorption of Heavy Metals in Industrial Wastewater by Magnetic Nano-particles

NASA Astrophysics Data System (ADS)

Tu, Y.; You, C.

2010-12-01

Industrial wastewater containing heavy metals is of great concern because of their toxic impact to living species and environments. Removal of metal ions from industrial effluent using nano-particles is an area of extensive research. This study collected wastewaters and effluents from 11 industrial companies in tanning, electronic plating, printed circuit board manufacturing, semi-conductor, and metal surface treatment industry and studied in detailed the major and trace element compositions to develop potential fingerprinting technique for pollutant source identification. The results showed that electronic plating and metal surface treatment industry produce high Fe, Mn, Cr, Zn, Ni and Mo wastewater. The tanning industry and the printed circuit board manufacturing industry released wastewater with high Fe and Cr, Cu and Ni, respectively. For semi-conductor industry, significant dissolved In was detected in wastewater. The absorption experiments to remove heavy metals in waters were conducted using Fe3O4 nano-particles. Under optimal conditions, more than 99 % dissolved metals were removed in a few minutes.

Recovery of tin from metal powders of waste printed circuit boards.

PubMed

Yang, Tianzu; Zhu, Pengchun; Liu, Weifeng; Chen, Lin; Zhang, Duchao

2017-10-01

To avoid the adverse effects of tin on the smelting process used to recover copper from metal powders of waste printed circuit boards, an effective process is proposed that selectively extracts tin and its associated metals. That impacts of alkaline pressure oxidation leaching parameters on metal conversion were systematically investigated. The results showed that Sn, Pb, Al and small amounts of Zn in the metal powders were leached out, leaving copper residue. By optimizing the conditions, leaching recovery of 98.2%, 77.6%, 78.3 and 6.8% for Sn, Pb, Al and Zn, respectively, were achieved. Subsequently, more than 99.9% of Pb and Zn in the leaching solution were removed as a mixture of PbS-ZnS in the purification process, which can be used as a raw material in Pb smelting. Approximately 86.2% of Sn in the purified solution was recovered by electrowinning, and the purity of the cathode tin was over 99.8%. Copyright © 2017 Elsevier Ltd. All rights reserved.

Soldering mask laser removal from printed circuit boards aiming copper recycling.

PubMed

Raele, Marcus Paulo; De Pretto, Lucas Ramos; Zezell, Denise Maria

2017-10-01

Management of waste of electric and electronic equipment (WEEE) is a key issue for modern societies; furthermore, it contains valuable materials that can be recycled, especially in printed circuit boards (PCB), which have approximately one-third of their weight in copper. In this study we demonstrated the use of laser to strip the covering soldering mask on PCB's, thus exposing the copper underneath so that extraction techniques may take place. Using a Q-Switched Nd:YAG laser operating at 1064nm and 532nm we tested the procedure under different energy conditions. The laser stripping of the soldering mask was achieved with satisfactory results by irradiation with 225mJ at 1064nm. However, when using similar parameters at 532nm the process of the coating ejection was not promoted properly, leading to a faulty detachment. Infrared laser PCB stripping presents itself to be technically viable and environmental friendly, since it uses no chemicals inputs, offering one more option to WEEE treatment and recycling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of Printed Circuit Board Technology to FT-ICR MS Analyzer Cell Construction and Prototyping

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leach, Franklin E.; Norheim, Randolph V.; Anderson, Gordon A.

Although Fourier transform ion cyclotron resonance mass spectrometry (FT-ICRMS) remains themass spectrometry platform that provides the highest levels of performance for mass accuracy and resolving power, there is room for improvement in analyzer cell design as the ideal quadrupolar trapping potential has yet to be generated for a broadband MS experiment. To this end, analyzer cell designs have improved since the field’s inception, yet few research groups participate in this area because of the high cost of instrumentation efforts. As a step towards reducing this barrier to participation and allowing for more designs to be physically tested, we introduce amore » method of FT-ICR analyzer cell prototyping utilizing printed circuit boards at modest vacuum conditions. This method allows for inexpensive devices to be readily fabricated and tested over short intervals and should open the field to laboratories lacking or unable to access high performance machine shop facilities because of the required financial investment.« less

A 128-channel picoammeter system and its application on charged particle beam current distribution measurements.

PubMed

Yu, Deyang; Liu, Junliang; Xue, Yingli; Zhang, Mingwu; Cai, Xiaohong; Hu, Jianjun; Dong, Jinmei; Li, Xin

2015-11-01

A 128-channel picoammeter system is constructed based on instrumentation amplifiers. Taking advantage of a high electric potential and narrow bandwidth in DC energetic charged beam measurements, a current resolution better than 5 fA can be achieved. Two sets of 128-channel strip electrodes are implemented on printed circuit boards and are employed for ion and electron beam current distribution measurements. Tests with 60 keV O(3+) ions and 2 keV electrons show that it can provide exact boundaries when a positive charged particle beam current distribution is measured.

Diagnosis of cardiovascular diseases based on diffuse optical tomography system

NASA Astrophysics Data System (ADS)

Yu, Zong-Han; Wu, Chun-Ming; Lin, Yo-Wei; Chuang, Ming-Lung; Tsai, Jui-che; Sun, Chia-Wei

2008-02-01

Diffuse optical tomography (DOT) is a technique to assess the spatial variation in absorption and scattering properties of the biological tissues. DOT provides the measurement of changes in concentrations of oxy-hemoglobin and deoxy-hemoglobin. The oxygenation images are reconstructed by the measured optical signals with nearest-neighbor pairs of sources and detectors. In our study, a portable DOT system is built with optode design on a flexible print circuit board (FPCB). In experiments, the hemodynamics temporal evolution of exercises and vessel occlusions are observed with in vivo measurements form normal subjects and some patients in intensive care unit.

Design and Prototyping of a High Granularity Scintillator Calorimeter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zutshi, Vishnu

A novel approach for constructing fine-granularity scintillator calorimeters, based on the concept of an Integrated Readout Layer (IRL) was developed. The IRL consists of a printed circuit board inside the detector which supports the directly-coupled scintillator tiles, connects to the surface-mount SiPMs and carries the necessary front-end electronics and signal/bias traces. Prototype IRLs using this concept were designed, prototyped and successfully exposed to test beams. Concepts and implementations of an IRL carried out with funds associated with this contract promise to result in the next generation of scintillator calorimeters.

Maze solving automatons for self-healing of open interconnects: Modular add-on for circuit boards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nair, Aswathi; Raghunandan, Karthik; Yaswant, Vaddi

We present the circuit board integration of a self-healing mechanism to repair open faults. The electric field driven mechanism physically restores fractured interconnects in electronic circuits and has the ability to solve mazes. The repair is performed by conductive particles dispersed in an insulating fluid. We demonstrate the integration of the healing module onto printed circuit boards and the ability of maze solving. We model and perform experiments on the influence of the geometry of conductive particles as well as the terminal impedances of the route on the healing efficiency. The typical heal rate is 10 μm/s with healed route havingmore » mean resistance of 8 kΩ across a 200 micron gap and depending on the materials and concentrations used.« less

A flexible surface wetness sensor using a RFID technique.

PubMed

Yang, Cheng-Hao; Chien, Jui-Hung; Wang, Bo-Yan; Chen, Ping-Hei; Lee, Da-Sheng

2008-02-01

This paper presents a flexible wetness sensor whose detection signal, converted to a binary code, is transmitted through radio-frequency (RF) waves from a radio-frequency identification integrated circuit (RFID IC) to a remote reader. The flexible sensor, with a fixed operating frequency of 13.56 MHz, contains a RFID IC and a sensor circuit that is fabricated on a flexible printed circuit board (FPCB) using a Micro-Electro-Mechanical-System (MEMS) process. The sensor circuit contains a comb-shaped sensing area surrounded by an octagonal antenna with a width of 2.7 cm. The binary code transmitted from the RFIC to the reader changes if the surface conditions of the detector surface changes from dry to wet. This variation in the binary code can be observed on a digital oscilloscope connected to the reader.

Development of a highly reliable composite board for printed circuitry for use in space environment

NASA Technical Reports Server (NTRS)

Bradbury, E. J.; Markle, R. A.; Dunnavant, W. R.; Stickney, P. B.

1971-01-01

Materials, processes and fabrication techniques have been investigated for the development of a high-temperature circuit-board laminate. High quality, void-free copper-clad laminates have been made using 7628/HS-1 style fiberglas reinforcements with filled polyimide matrices. The fabricating characteristics of P13N resin appear suitable for use as a filled matrix in this circuit board development. High-fired, ball-milled alumina appears to be necessary to obtain the desired effects in the circuit board system. Nickel-clad copper foil bonding surfaces appear to be another requirement for retention of good bond strengths after art work and plating sequences. The fabrication cycle for this circuit board system is very dependent on the heating profile. Very rapid heating with quick loading is recommended. A stack approach to lamination was successfully used.

Screen printing technology applied to silicon solar cell fabrication

NASA Technical Reports Server (NTRS)

Thornhill, J. W.; Sipperly, W. E.

1980-01-01

The process for producing space qualified solar cells in both the conventional and wraparound configuration using screen printing techniques was investigated. Process modifications were chosen that could be easily automated or mechanized. Work was accomplished to optimize the tradeoffs associated with gridline spacing, gridline definition and junction depth. An extensive search for possible front contact metallization was completed. The back surface field structures along with the screen printed back contacts were optimized to produce open circuit voltages of at least an average of 600 millivolts. After all intended modifications on the process sequence were accomplished, the cells were exhaustively tested. Electrical tests at AMO and 28 C were made before and after boiling water immersion, thermal shock, and storage under conditions of high temperature and high humidity.

Radiation polymerisable compositions containing 3-sorboyloxy-2-hydroxypropyl groups

DOE Office of Scientific and Technical Information (OSTI.GOV)

Green, G.E.

1976-02-03

Compounds having at least three 3-sorboyloxy-2-hydroxypropyl groups directly attached to ether oxygen atoms are polymerised by exposure to actinic radiation, preferably in the presence of a sensitizer such as Michler's ketone or benzoin. The compounds may be obtained by the reaction either of sorbic acid with a substance having at least three glycidyl ether groups or of glycidyl sorbate with a substance having at least three phenolic or alcoholic hydroxyl groups: if desired, not all of the glycidyl groups may be consumed, so that, after actinically induced polymerisation, the epoxide-containing polymer may be cross-linked by reaction with a curing agentmore » for epoxide resins. The compounds are useful in making printed circuits or printing plates for offset printing.« less

Interchip link system using an optical wiring method.

PubMed

Cho, In-Kui; Ryu, Jin-Hwa; Jeong, Myung-Yung

2008-08-15

A chip-scale optical link system is presented with a transmitter/receiver and optical wire link. The interchip link system consists of a metal optical bench, a printed circuit board module, a driver/receiver integrated circuit, a vertical cavity surface-emitting laser/photodiode array, and an optical wire link composed of plastic optical fibers (POFs). We have developed a downsized POF and an optical wiring method that allows on-site installation with a simple annealing as optical wiring technologies for achieving high-density optical interchip interconnection within such devices. Successful data transfer measurements are presented.

IEEE 1990 International Symposium on Electromagnetic Compatibility, Washington, DC, Aug. 21-23, 1990, Record

NASA Astrophysics Data System (ADS)

The present conference discusses topics in EM shielding effectiveness, system-level EMC, EMP effects, circuit-level EMI testing, EMI control, analysis techniques for system-level EMC, EMP protective measures, EMI test methods, electrostatic-discharge testing, printed circuit-board design for EMC, and EM environment effects. Also discussed are EMI measurement procedures, EM spectrum-management issues for the 21st century, antenna and propagation effects on EMI testing, EMI control in cables, socioeconomic aspects of EMC, systemwide EMI controls, and EM radiation and coupling.

Low-dielectric constant insulators for future integrated circuits and packages.

PubMed

Kohl, Paul A

2011-01-01

Future integrated circuits and packages will require extraordinary dielectric materials for interconnects to allow transistor advances to be translated into system-level advances. Exceedingly low-permittivity and low-loss materials are required at every level of the electronic system, from chip-level insulators to packages and printed wiring boards. In this review, the requirements and goals for future insulators are discussed followed by a summary of current state-of-the-art materials and technical approaches. Much work needs to be done for insulating materials and structures to meet future needs.

Waste Minimization Assessment for Multilayered Printed Circuit Board Manufacturing

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manu facturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at s...

40 CFR 413.82-413.83 - [Reserved

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 413.82-413.83 Section 413.82-413.83 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ELECTROPLATING POINT SOURCE CATEGORY Printed Circuit Board Subcategory §§ 413.82-413.83 [Reserved] ...

WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PROTOTYPE PRINTED CIRCUIT BOARDS

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

Printed Circuit Board Design (PCB) with HDL Designer

NASA Technical Reports Server (NTRS)

Winkert, Thomas K.; LaFourcade, Teresa

2004-01-01

Contents include the following: PCB design with HDL designer, design process and schematic capture - symbols and diagrams: 1. Motivation: time savings, money savings, simplicity. 2. Approach: use single tool PCB for FPGA design, more FPGA designs than PCB designers. 3. Use HDL designer for schematic capture.

MODIFICATIONS TO REDUCE DRAG OUT AT A PRINTED CIRCUIT BOARD MANUFACTURER

EPA Science Inventory

This MnTAP/EPA Waste Reduction Innovative Technology Evaluation project at Micom, Inc., demonstrated the waste reducing capability of two simple rinsing modifications on an etchant and an electroless copper process. he simple, tow (or no) cost, low technology changes that were ma...

Field-Programmable Gate Array-based fluxgate magnetometer with digital integration

NASA Astrophysics Data System (ADS)

Butta, Mattia; Janosek, Michal; Ripka, Pavel

2010-05-01

In this paper, a digital magnetometer based on printed circuit board fluxgate is presented. The fluxgate is pulse excited and the signal is extracted by gate integration. We investigate the possibility to perform integration on very narrow gates (typically 500 ns) by using digital techniques. The magnetometer is based on field-programmable gate array (FPGA) card: we will show all the advantages and disadvantages, given by digitalization of fluxgate output voltage by means of analog-to-digital converter on FPGA card, as well as digitalization performed by external digitizer. Due to very narrow gate, it is shown that a magnetometer entirely based on a FPGA card is preferable, because it avoids noise due to trigger instability. Both open loop and feedback operative mode are described and achieved results are presented.

Screen-Printed Washable Electronic Textiles as Self-Powered Touch/Gesture Tribo-Sensors for Intelligent Human-Machine Interaction.

PubMed

Cao, Ran; Pu, Xianjie; Du, Xinyu; Yang, Wei; Wang, Jiaona; Guo, Hengyu; Zhao, Shuyu; Yuan, Zuqing; Zhang, Chi; Li, Congju; Wang, Zhong Lin

2018-05-22

Multifunctional electronic textiles (E-textiles) with embedded electric circuits hold great application prospects for future wearable electronics. However, most E-textiles still have critical challenges, including air permeability, satisfactory washability, and mass fabrication. In this work, we fabricate a washable E-textile that addresses all of the concerns and shows its application as a self-powered triboelectric gesture textile for intelligent human-machine interfacing. Utilizing conductive carbon nanotubes (CNTs) and screen-printing technology, this kind of E-textile embraces high conductivity (0.2 kΩ/sq), high air permeability (88.2 mm/s), and can be manufactured on common fabric at large scales. Due to the advantage of the interaction between the CNTs and the fabrics, the electrode shows excellent stability under harsh mechanical deformation and even after being washed. Moreover, based on a single-electrode mode triboelectric nanogenerator and electrode pattern design, our E-textile exhibits highly sensitive touch/gesture sensing performance and has potential applications for human-machine interfacing.

Gigahertz Electromagnetic Structures via Direct Ink Writing for Radio-Frequency Oscillator and Transmitter Applications.

PubMed

Zhou, Nanjia; Liu, Chengye; Lewis, Jennifer A; Ham, Donhee

2017-04-01

Radio-frequency (RF) electronics, which combine passive electromagnetic devices and active transistors to generate and process gigahertz (GHz) signals, provide a critical basis of ever-pervasive wireless networks. While transistors are best realized by top-down fabrication, relatively larger electromagnetic passives are within the reach of printing techniques. Here, direct writing of viscoelastic silver-nanoparticle inks is used to produce a broad array of RF passives operating up to 45 GHz. These include lumped devices such as inductors and capacitors, and wave-based devices such as transmission lines, their resonant networks, and antennas. Moreover, to demonstrate the utility of these printed RF passive structures in active RF electronic circuits, they are combined with discrete transistors to fabricate GHz self-sustained oscillators and synchronized oscillator arrays that provide RF references, and wireless transmitters clocked by the oscillators. This work demonstrates the synergy of direct ink writing and RF electronics for wireless applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparison of conductor and dielectric inks in printed organic complementary transistors

NASA Astrophysics Data System (ADS)

Ng, Tse Nga; Mei, Ping; Whiting, Gregory L.; Schwartz, David E.; Abraham, Biby; Wu, Yiliang; Veres, Janos

2014-10-01

Two types of printable conductor and a bilayer gate dielectric are evaluated for use in all-additive, inkjetprinted complementary OTFTs. The Ag nanoparticle ink based on nonpolar alkyl amine surfactant or stabilizer enables good charge injection into p-channel devices, but this ink also leaves residual stabilizer that modifies the transistor backchannel and shifts the turn-on voltage to negative values. The Ag ink based on polar solvent requires dopant modification to improve charge injection to p-channel devices, but this ink allows the OTFT turn-on voltage to be close to 0 V. The reverse trend is observed for n-channel OTFTs. For gate insulator, a bilayer dielectric is demonstrated that combines the advantages of two types of insulator materials, in which a fluoropolymer reduces dipolar disorder at the semiconductor-dielectric interface, while a high-k PVDF terpolymer dielectric facilitates high gate capacitance. The dielectric is incorporated into an inverter and a three-stage ring oscillator, and the resulting circuits were demonstrated to operate at a supply voltage as low as 2 V, with bias stress levels comparable to circuits with other types of dielectrics.

The influence of printed electronics on the recyclability of paper: a case study for smart envelopes in courier and postal services.

PubMed

Aliaga, C; Zhang, H; Dobon, A; Hortal, M; Beneventi, D

2015-04-01

The aim of this paper is to analyse the effects of the presence of printed electronics on the paper waste streams and specifically on paper recyclability. The analysis is based on a case study focussed on envelopes for postal and courier services provided with these intelligent systems. The smart printed envelope of the study includes a combination of both conventional (thin flexible batteries and resistors) and printed electronic components (conductive track layout based on nanosilver ink). For this purpose, a comparison between envelopes with and without these components (batteries, resistors and conductive track layouts) was carried out through pilot scale paper recycling tests. The generation of rejects during the recycling process as well as the final quality of the recycled paper (mechanical and optical properties) were tested and quantitatively evaluated. The results show that resistors are retained during the screening process in the sieves and consequently they cannot end up in the final screened pulp. Therefore, mechanical and optical properties of the recycled paper are not affected. Nevertheless, inks from the conductive track layouts and batteries were partially dissolved in the process water. These substances were not totally retained in the sieving systems resulting in slight changes in the optical properties of the final recycled paper (variations are 7.2-7.5% in brightness, 8.5-10.7% in whiteness, 1.2-2.2% in L(∗) values, 3.3-3.5% in opacity and 16.1-27% in yellowness). These variations are not in ranges able to cause problems in current paper recycling processes and restrict the use of recycled paper in current applications. Moreover, real impacts on industrial recycling are expected to be even significantly lower since the proportion of paper product with printed circuits in the current paper waste streams are much lower than the ones tested in this work. However, it should be underlined the fact that this situation may change over the next years due to the future developments in printed electronics and the gradual penetration of these types of devices in the market. Copyright © 2015 Elsevier Ltd. All rights reserved.

Elemental analysis of printed circuit boards considering the ROHS regulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wienold, Julia, E-mail: julia.wienold@bam.de; Recknagel, Sebastian, E-mail: sebastian.recknagel@bam.de; Scharf, Holger, E-mail: holger.scharf@bam.de

2011-03-15

The EU RoHS Directive (2002/95/EC of the European Parliament and of the Council) bans the placing of new electrical and electronic equipment containing more than agreed levels of lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyl (PBB) and polybrominated diphenyl ether (PBDE) flame retardants on the EU market. It necessitates methods for the evaluation of RoHS compliance of assembled electronic equipment. In this study mounted printed circuit boards from personal computers were analyzed on their content of the three elements Cd, Pb and Hg which were limited by the EU RoHS directive. Main focus of the investigations was the influence ofmore » sample pre-treatment on the precision and reproducibility of the results. The sample preparation steps used were based on the guidelines given in EN 62321. Five different types of dissolution procedures were tested on different subsequent steps of sample treatment like cutting and milling. Elemental analysis was carried out using ICP-OES, XRF and CV-AFS (Hg). The results obtained showed that for decision-making with respect to RoHS compliance a size reduction of the material to be analyzed to particles {<=}1.5 mm can already be sufficient. However, to ensure analytical results with relative standard deviations of less than 20%, as recommended by the EN 62321, a much larger effort for sample processing towards smaller particle sizes might be required which strongly depends on the mass fraction of the element under investigation.« less

Advanced sensor systems for biotelemetry

NASA Technical Reports Server (NTRS)

Ricks, Robert D. (Inventor); Mundt, Carsten W. (Inventor); Hines, John W. (Inventor); Somps, Christopher J. (Inventor)

2003-01-01

The present invention relates to telemetry-based sensing systems that continuously measures physical, chemical and biological parameters. More specifically, these sensing systems comprise a small, modular, low-power implantable biotelemetry system capable of continuously sensing physiological characteristics using implantable transmitters, a receiver, and a data acquisition system to analyze and record the transmitted signal over several months. The preferred embodiment is a preterm labor and fetal monitoring system. Key features of the invention include Pulse Interval Modulation (PIM) that is used to send temperature and pressure information out of the biological environment. The RF carrier frequency is 174-216 MHz and a pair of RF bursts (pulses) is transmitted at a frequency of about 1-2 Hz. The transmission range is 3 to 10 feet, depending on the position of the transmitter in the body and its biological environment. The entire transmitter is encapsulated in biocompatible silicone rubber. Power is supplied by on-board silver-oxide batteries. The average power consumption of the current design is less than 30 .mu.W., which yields a lifetime of approximately 6-9 months. Chip-on-Board technology (COB) drastically reduces the size of the printed circuit board from 38.times.28 mm to 22.times.8 mm. Unpackaged dies are flip-chip bonded directly onto the printed circuit board, along with surface mount resistors and capacitors. The invention can monitor additional physiological parameters including, but not limited to, ECG, blood gases, glucose, and ions such as calcium, potassium, and sodium.

Advanced Sensor Systems for Biotelemetry

NASA Technical Reports Server (NTRS)

Hines, John W. (Inventor); Somps, Christopher J. (Inventor); Ricks, Robert D. (Inventor); Mundt, Carsten W. (Inventor)

2003-01-01

The present invention relates to telemetry-based sensing systems that continuously measures physical, chemical and biological parameters. More specifically, these sensing systems comprise a small, modular, low-power implantable biotelemetry system capable of continuously sensing physiological characteristics using implantable transmitters, a receiver, and a data acquisition system to analyze and record the transmitted signal over several months. The preferred embodiment is a preterm labor and fetal monitoring system. Key features of the invention include Pulse Interval Modulation (PIM) that is used to send temperature and pressure information out of the biological environment. The RF carrier frequency is 174-216 MHz and a pair of RF bursts (pulses) is transmitted at a frequency of about 1-2 Hz. The transmission range is 3 to 10 feet, depending on the position of the transmitter in the body and its biological environment. The entire transmitter is encapsulated in biocompatible silicone rubber. Power is supplied by on-board silver-oxide batteries. The average power consumption of the current design is less than 30 microW, which yields a lifetime of approximately 6 - 9 months. Chip-on-Board technology (COB) drastically reduces the size of the printed circuit board from 38 x 28 mm to 22 x 8 mm. Unpackaged dies are flip-chip bonded directly onto the printed circuit board, along with surface mount resistors and capacitors. The invention can monitor additional physiological parameters including, but not limited to, ECG, blood gases, glucose, and ions such as calcium, potassium, and sodium.

An Open Hardware seismic data recorder - a solid basis for citizen science

NASA Astrophysics Data System (ADS)

Mertl, Stefan

2015-04-01

"Ruwai" is a 24-Bit Open Hardware seismic data recorder. It is built up of four stackable printed circuit boards fitting the Arduino Mega 2560 microcontroller prototyping platform. An interface to the BeagleBone Black single-board computer enables extensive data storage, -processing and networking capabilities. The four printed circuit boards provide a uBlox Lea-6T GPS module and real-time clock (GPS Timing shield), an Texas Instruments ADS1274 24-Bit analog to digital converter (ADC main shield), an analog input section with a Texas Instruments PGA281 programmable gain amplifier and an analog anti-aliasing filter (ADC analog interface pga) and the power conditioning based on 9-36V DC input (power supply shield). The Arduino Mega 2560 is used for controlling the hardware components, timestamping sampled data using the GPS timing information and transmitting the data to the BeagleBone Black single-board computer. The BeagleBone Black provides local data storage, wireless mesh networking using the optimized link state routing daemon and differential GNSS positioning using the RTKLIB software. The complete hardware and software is published under free software - or open hardware licenses and only free software (e.g. KiCad) was used for the development to facilitate the reusability of the design and increases the sustainability of the project. "Ruwai" was developed within the framework of the "Community Environmental Observation Network (CEON)" (http://www.mertl-research.at/ceon/) which was supported by the Internet Foundation Austria (IPA) within the NetIdee 2013 call.

Advanced On-Board Processor (AOP). [for future spacecraft applications

NASA Technical Reports Server (NTRS)

1973-01-01

Advanced On-board Processor the (AOP) uses large scale integration throughout and is the most advanced space qualified computer of its class in existence today. It was designed to satisfy most spacecraft requirements which are anticipated over the next several years. The AOP design utilizes custom metallized multigate arrays (CMMA) which have been designed specifically for this computer. This approach provides the most efficient use of circuits, reduces volume, weight, assembly costs and provides for a significant increase in reliability by the significant reduction in conventional circuit interconnections. The required 69 CMMA packages are assembled on a single multilayer printed circuit board which together with associated connectors constitutes the complete AOP. This approach also reduces conventional interconnections thus further reducing weight, volume and assembly costs.

Superconducting Multilayer High-Density Flexible Printed Circuit Board for Very High Thermal Resistance Interconnections

NASA Astrophysics Data System (ADS)

de la Broïse, Xavier; Le Coguie, Alain; Sauvageot, Jean-Luc; Pigot, Claude; Coppolani, Xavier; Moreau, Vincent; d'Hollosy, Samuel; Knarosovski, Timur; Engel, Andreas

2018-05-01

We have successively developed two superconducting flexible PCBs for cryogenic applications. The first one is monolayer, includes 552 tracks (10 µm wide, 20 µm spacing), and receives 24 wire-bonded integrated circuits. The second one is multilayer, with one track layer between two shielding layers interconnected by microvias, includes 37 tracks, and can be interconnected at both ends by wire bonding or by connectors. The first cold measurements have been performed and show good performances. The novelty of these products is, for the first one, the association of superconducting materials with very narrow pitch and bonded integrated circuits and, for the second one, the introduction of a superconducting multilayer structure interconnected by vias which is, to our knowledge, a world-first.

A programmable CCD driver circuit for multiphase CCD operation

NASA Technical Reports Server (NTRS)

Ewin, Audrey J.; Reed, Kenneth V.

1989-01-01

A programmable CCD (charge-coupled device) driver circuit was designed to drive CCDs in multiphased modes. The purpose of the drive electronics is to operate developmental CCD imaging arrays for NASA's tiltable moderate resolution imaging spectrometer (MODIS-T). Five objectives for the driver were considered during its design: (1) the circuit drives CCD electrode voltages between 0 V and +30 V to produce reasonable potential wells, (2) the driving sequence is started with one input signal, (3) the driving sequence is started with one input signal, (4) the circuit allows programming of frame sequences required by arrays of any size, (5) it produces interfacing signals for the CCD and the DTF (detector test facility). Simulation of the driver verified its function with the master clock running up to 10 MHz. This suggests a maximum rate of 400,000 pixels/s. Timing and packaging parameters were verified. The design uses 54 TTL (transistor-transistor logic) chips. Two versions of hardware were fabricated: wirewrap and printed circuit board. Both were verified functionally with a logic analyzer.

Test Bench for Coupling and Shielding Magnetic Fields

NASA Astrophysics Data System (ADS)

Jordan, J.; Esteve, V.; Dede, E.; Sanchis, E.; Maset, E.; Ferreres, A.; Ejea, J. B.; Cases, C.

2016-05-01

This paper describes a test bench for training purposes, which uses a magnetic field generator to couple this magnetic field to a victim circuit. It can be very useful to test for magnetic susceptibility as well. The magnetic field generator consists of a board, which generates a variable current that flows into a printed circuit board with spiral tracks (noise generator). The victim circuit consists of a coaxial cable concentric with the spiral tracks and its generated magnetic field. The coaxial cable is part of a circuit which conducts a signal produced by a signal generator and a resistive load. In the paper three cases are studied. First, the transmitted signal from the signal generator uses the central conductor of the coaxial cable and the shield is floating. Second, the shield is short circuited at its ends (and thus forming a loop). Third, when connecting the shield in series with the inner conductor and therefore having the current flowing into the coax via the inner conductor and returning via the shield.

Experimental Verification of Guided-Wave Lumped Circuits Using Waveguide Metamaterials

NASA Astrophysics Data System (ADS)

Li, Yue; Zhang, Zhijun

2018-04-01

Through the construction and characterization in microwave frequencies, we experimentally demonstrate our recently developed theory of waveguide lumped circuits, i.e., waveguide metatronics [Sci. Adv. 2, e1501790 (2016), 10.1126/sciadv.1501790], as a method to design subwavelength-scaled analog circuits. In the paradigm of waveguide metatronics, numbers of lumped inductors and capacitors are easily integrated functionally inside the waveguide, which is an irreplaceable transmission line in millimeter-wave and terahertz systems with the advantages of low radiation loss and low crosstalk. An example of multiple-ordered metatronic filters with layered structures is fabricated utilizing the technique of substrate integrated waveguides, which can be easily constructed by the printed-circuit-board process. The materials used in the construction are also typical microwave materials with positive permittivity, low loss, and negligible dispersion, imitating the plasmonic materials with negative permittivity in the optical domain. The results verify the theory of waveguide metatronics, which provides an efficient platform of functional lumped circuit design for guided-wave processing.

Characterization and mechanical separation of metals from computer Printed Circuit Boards (PCBs) based on mineral processing methods.

PubMed

Sarvar, Mojtaba; Salarirad, Mohammad Mehdi; Shabani, Mohammad Amin

2015-11-01

In this paper, a novel mechanical process is proposed for enriching metal content of computer Printed Circuit Boards (PCBs). The PCBs are crushed and divided into three different size fractions namely: -0.59, +0.59 to 1.68 and +1.68 mm. Wet jigging and froth flotation methods are selected for metal enrichment. The coarse size fraction (+1.68 mm) is processed by jigging. The plastic free product is grinded and screened. The oversized product is separated as the first concentrate. It was rich of metal because the grinding process was selective. The undersized product is processed by froth flotation. Based on the obtained results, the middle size fraction (+0.59 to 1.68 mm) and the small size fraction (-0.59 mm) are processed by wet jigging and froth flotation respectively. The wet jigging process is optimized by investigating the effect of pulsation frequency and water flow rate. The results of examining the effect of particle size, solid to liquid ratio, conditioning time and using apolar collector showed that collectorless flotation is a promising method for separating nonmetals of PCBs. 95.6%, 97.5% and 85% of metal content of coarse size, middle size and small size fraction are recovered. The grades of obtained concentrates were 63.3%, 92.5% and 75% respectively. The total recovery is calculated as 95.64% and the grade of the final concentrate was 71.26%. Determining the grade of copper and gold in the final product reveals that 4.95% of copper and 24.46% of gold are lost during the concentration. The major part of the lost gold is accumulated in froth flotation tail. Copyright © 2015 Elsevier Ltd. All rights reserved.

Printable inorganic nanomaterials for flexible transparent electrodes: from synthesis to application

NASA Astrophysics Data System (ADS)

Wang, Dingrun; Mei, Yongfeng; Huang, Gaoshan

2018-01-01

Printed and flexible electronics are definitely promising cutting-edge electronic technologies of the future. They offer a wide-variety of applications such as flexible circuits, flexible displays, flexible solar cells, skin-like pressure sensors, and radio frequency identification tags in our daily life. As the most-fundamental component of electronics, electrodes are made of conductive materials that play a key role in flexible and printed electronic devices. In this review, various inorganic conductive materials and strategies for obtaining highly conductive and uniform electrodes are demonstrated. Applications of printed electrodes fabricated via these strategies are also described. Nevertheless, there are a number of challenges yet to overcome to optimize the processing and performance of printed electrodes. Project supported by the National Natural Science Foundation of China (Nos. 51475093, U1632115), the Science and Technology Commission of Shanghai Municipality (No. 14JC1400200), the National Key Technologies R&D Program of China (No. 2015ZX02102-003), and the Changjiang Young Scholars Programme of China.

The DMON2: A Commercially Available Broadband Acoustic Monitoring Instrument

DTIC Science & Technology

2015-09-30

the need for a new system design. o Seamless integration of the DMON2 with multiple platforms: Slocum and Wave Gliders, moored real-time buoys and...and robustness (stainless steel design). Transducer Head Printed Circuit Board (PCB): We have completed the design and fabrication of the DMON2

78 FR 64569 - Self-Regulatory Organizations; NASDAQ OMX PHLX LLC; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-29

... United States Court of Appeals for the District of Columbia Circuit in NetCoaliton v. SEC, 615 F.3d 525... with the provisions of 5 U.S.C. 552, will be available for Web site viewing and printing in the...

ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PRINTED CIRCUIT BOARDS

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

Electric Current Solves Mazes

ERIC Educational Resources Information Center

Ayrinhac, Simon

2014-01-01

We present in this work a demonstration of the maze-solving problem with electricity. Electric current flowing in a maze as a printed circuit produces Joule heating and the right way is instantaneously revealed with infrared thermal imaging. The basic properties of electric current can be discussed in this context, with this challenging question:…

TSCA Work Plan Chemical Problem Formulation and Initial Assessment Tetrabromobisphenol A and Related Chemicals Cluster Flame Retardants

EPA Pesticide Factsheets

EPA released a problem formulation for TBBPA and related chemicals used as a flame retardants in plastics/printed circuit boards for electronics. The goal of this problem formulation was to identify scenarios where further risk analysis may be necessary.

Use of high-radiant flux, high-resolution DMD light engines in industrial applications

NASA Astrophysics Data System (ADS)

Müller, Alexandra; Ram, Surinder

2014-03-01

The field of application of industrial projectors is growing day by day. New Digital Micromirror Device (DMD) - based applications like 3D printing, 3D scanning, Printed Circuit Board (PCB) board printing and others are getting more and more sophisticated. The technical demands for the projection system are rising as new and more stringent requirements appear. The specification for industrial projection systems differ substantially from the ones of business and home beamers. Beamers are designed to please the human eye. Bright colors and image enhancement are far more important than uniformity of the illumination or image distortion. The human eye, followed by the processing of the brain can live with quite high intensity variations on the screen and image distortion. On the other hand, a projector designed for use in a specialized field has to be tailored regarding its unique requirements in order to make no quality compromises. For instance, when the image is projected onto a light sensitive resin, a good uniformity of the illumination is crucial for good material hardening (curing) results. The demands on the hardware and software are often very challenging. In the following we will review some parameters that have to be considered carefully for the design of industrial projectors in order to get the optimum result without compromises.

OptoZIF Drive: a 3D printed implant and assembly tool package for neural recording and optical stimulation in freely moving mice

NASA Astrophysics Data System (ADS)

Freedman, David S.; Schroeder, Joseph B.; Telian, Gregory I.; Zhang, Zhengyang; Sunil, Smrithi; Ritt, Jason T.

2016-12-01

Objective. Behavioral neuroscience studies in freely moving rodents require small, light-weight implants to facilitate neural recording and stimulation. Our goal was to develop an integrated package of 3D printed parts and assembly aids for labs to rapidly fabricate, with minimal training, an implant that combines individually positionable microelectrodes, an optical fiber, zero insertion force (ZIF-clip) headstage connection, and secondary recording electrodes, e.g. for electromyography (EMG). Approach. Starting from previous implant designs that position recording electrodes using a control screw, we developed an implant where the main drive body, protective shell, and non-metal components of the microdrives are 3D printed in parallel. We compared alternative shapes and orientations of circuit boards for electrode connection to the headstage, in terms of their size, weight, and ease of wire insertion. We iteratively refined assembly methods, and integrated additional assembly aids into the 3D printed casing. Main results. We demonstrate the effectiveness of the OptoZIF Drive by performing real time optogenetic feedback in behaving mice. A novel feature of the OptoZIF Drive is its vertical circuit board, which facilities direct ZIF-clip connection. This feature requires angled insertion of an optical fiber that still can exit the drive from the center of a ring of recording electrodes. We designed an innovative 2-part protective shell that can be installed during the implant surgery to facilitate making additional connections to the circuit board. We use this feature to show that facial EMG in mice can be used as a control signal to lock stimulation to the animal’s motion, with stable EMG signal over several months. To decrease assembly time, reduce assembly errors, and improve repeatability, we fabricate assembly aids including a drive holder, a drill guide, an implant fixture for microelectode ‘pinning’, and a gold plating fixture. Significance. The expanding capability of optogenetic tools motivates continuing development of small optoelectric devices for stimulation and recording in freely moving mice. The OptoZIF Drive is the first to natively support ZIF-clip connection to recording hardware, which further supports a decrease in implant cross-section. The integrated 3D printed package of drive components and assembly tools facilities implant construction. The easy interfacing and installation of auxiliary electrodes makes the OptoZIF Drive especially attractive for real time feedback stimulation experiments.