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1

Heterojunction bipolar transistor using a (Ga,In)P emitter on a GaAs base, grown by molecular beam epitaxy  

Microsoft Academic Search

We report the first N-p-n heterojunction bipolar transistor (HBT) using a (Ga,In)P\\/GaAs heterojunction emitter on a GaAs base. This combination is of interest as a potential alternate to (Al,Ga)As\\/GaAs, because of theoretical predictions of a larger valence band discontinuity and a smaller conduction band discontinuity, thus eliminating the need for grading of the emitter\\/base junction. The structure was grown by

M. J. Mondry; H. Kroemer

1985-01-01

2

A new bipolar transistor - GAT  

NASA Astrophysics Data System (ADS)

A new bipolar transistor named Gate Associated Transistor (GAT) was proposed and the operating mechanisms were verified. The structure of the GAT has a unique base region consisting of an FET merged into the base of a standard bipolar transistor. The operating mechanisms and characteristics of the GAT were investigated and compared with those of standard power transistors. The most outstanding feature of the GAT was a large area for safe operation.

Kondo, H.; Yukimoto, Y.

1980-02-01

3

Super Matched Bipolar Transistor Pair Sets New  

E-print Network

Super Matched Bipolar Transistor Pair Sets New Standards for Drift and Noise Matched bipolar transistor pairs are a very powerful design tool, yet have received less and less attention over the last few transistor pairs was being limited by statistical fluctuations in the material itself and in the processing

Lanterman, Aaron

4

Bipolar transistor in VESTIC technology  

NASA Astrophysics Data System (ADS)

VESTIC technology was proposed as an alternative for traditional CMOS technology. It offers a new FET-type twin gate junctionless device called VeSFET. In addition, in the basic VESTIC device structure many different active devices can be made, including bipolar transistors. This allows easy integration of bipolar transistors (called here VeSBJT) with VeSFET transistors. The purpose of this paper is to investigate the expected properties of VeSBJT in order to answer the following questions: are the expected parameters of VeSBJT promising enough to justify further research and fabrication experiments, and will VeSBJTs be technologically compatible with VeSFETs? Our theoretical predictions are based on the concept of effective base width for bipolar transistors with non-plane-parallel emitter and collector junctions. The conclusion is that VeSBJT can be a device with useful characteristics. As a result, VESTIC may have the potential to become a new BiCMOS-type technology.

Ku?micz, Wies?aw; Mierzwi?ski, Piotr

2013-07-01

5

TILBW Bipolar Power Switching Transistor  

NASA Astrophysics Data System (ADS)

The work reports the development of TILBW (Two Interdigitation Levels with heavily-doped Base Wells) bipolar power switching transistors, which combine the main advantages of both TIL and GAT devices. The TILBW transistors exhibit the following many-fold advantages in comparison with identical, yet conventional devices of the same class (identical area and case) processed simultaneously: a reduction of the turn-on time by a factor of ˜ 20; a two-fold reduction of the fall time tf; an ˜ 18-percent increase of VCEO(SUS); an ˜ 23-percent increase of VCBO; an enhanced RBSOA.

Silard, Andrei P.; Nani, Gabriel

1989-03-01

6

Modeling Advanced Avalanche Effects for Bipolar Transistor Circuit Design  

E-print Network

Modeling Advanced Avalanche Effects for Bipolar Transistor Circuit Design Vladimir Milovanovi operating frequency and high output power of modern bipolar transistor circuits increase, designers are trying to exploit transistor operating regions where they would be able satisfy both conditions, namely

Technische Universiteit Delft

7

High Performance Lateral Schottky Collector Bipolar Transistors on SOI  

E-print Network

High Performance Lateral Schottky Collector Bipolar Transistors on SOI for VLSI Applications that the thesis entitled "High Performance Lateral Schottky Collector Bipolar Transistors on SOI for VLSI bipolar transistors play a vital role in RF/Microwave applications. But they need to satisfy stringent

Kumar, M. Jagadesh

8

Theory of semiconductor magnetic bipolar transistors M. E. Flattea)  

E-print Network

Theory of semiconductor magnetic bipolar transistors M. E. Flatte´a) and Z. G. Yu Optical Science April 2003 Bipolar transistors with a ferromagnetic base are shown theoretically to have the potential of a ``spin transistor.'' 1 A burst of recent activity demonstrating control- lable fabrication

Flatte, Michael E.

9

Mathematical modeling of the characteristics of bipolar heterojunction transistors  

SciTech Connect

The authors review the known methods of modeling bipolar heterojunction transistors (BHT) and illustrate that none of the available models is sufficiently universal. The authors develop a semi-empirical model which is valid for a wide number of heterojunctions, such as InSb-Ge, GaSb-Ge, CdS-Ge, GaAs-Ge, ZnSe-Ge, GaAs-Si, ZnSe-GaAs, etc., plus three-component compounds such as Als/bu z/Ga/sub 1-z/ As - GaAs. The assumptions underlying the model were confirmed experimentally in the cases when the heterojunction is formed by compounds of the group A/sub III/B/sub V/ with a common anion, such as CdTe-CdHgTe.

Butakova, N.G.; Valiev, K.A.; Zubov, A.V.; Orlikovskii, A.A.

1986-03-01

10

History and future perspective of the modern silicon bipolar transistor  

Microsoft Academic Search

A brief historical account of the development of advanced silicon bipolar transistors (SBTs) at IBM Research is described, with a focus on discussing the technical merits of the directions taken. A perspective on the future of silicon bipolar is given, including a discussion on the merits of SiGe-base transistors, and on the scaling limits of both Si-base and SiGe-base transistors.

Tak H. Ning

2001-01-01

11

Low Frequency Noise in Strained Si Heterojunction Bipolar Transistors  

Microsoft Academic Search

The low frequency noise performance of strained Si heterojunction bipolar transistors (sSi HBTs) is presented for the first time. Conventional SiGe HBTs and Si bipolar junction transistors (BJTs), processed with strained Si devices, were also measured as a reference. It is found that a lower noise level is obtained in sSi HBTs for a given collector current, which is im-

M. Fjer; S. Persson; E. Escobedo-Cousin; A. G. O'Neill

2011-01-01

12

RF SMALL SIGNAL AVALANCHE CHARACTERIZATION AND REPERCUSSIONS ON BIPOLAR TRANSISTOR CIRCUIT DESIGN  

E-print Network

RF SMALL SIGNAL AVALANCHE CHARACTERIZATION AND REPERCUSSIONS ON BIPOLAR TRANSISTOR CIRCUIT DESIGN transistor circuits, electronic circuit designers are exploring regimes of transistor operation that meet on some important transistor properties like unilateral and maximum available power gain, as well

Technische Universiteit Delft

13

Calculation of the emitter efficiency of bipolar transistors  

Microsoft Academic Search

The emitter efficiency of a bipolar transistor is calculated taking heavy doping effects such as impurity band formation and band tailing into account. It is shown that in most cases these effects, rather than the minority carrier lifetime in the emitter are limiting the transistor current gain. This allows us to define an effective emitter impurity profile for use in

ROBERT P. MERTENS; HUGO J. DEMAN; ROGER J. VAN OVERSTRAETEN

1973-01-01

14

Heterojunction bipolar transistor characterization using noncontact optical spectroscopy  

NASA Astrophysics Data System (ADS)

In this work we report the application of optical spectroscopic techniques namely photoreflectance (PR), ellipsometry and photoluminescence (PL) for qualification of InGaP/GaAs multi-layer heterojunction bipolar transistor (HBT) material. These techniques reveal important information regarding the quality of the different InGaP and GaAs layers for the emitter, base, collector and surface cap regions. In particular PR studies of non-optimal HBT material reveals InGaP (emitter) layer sub-lattice ordering effects, as correlated with selective area electron diffraction patterns. Moreover, comparison of the emitter/base interface field levels and InGaP ordering data reveals further evidence of a non-abrupt InGaP/GaAs heterojunction, proving to have adverse consequences for HBT current gain characteristics and consistent with measured reduced common emitter current gain. Supporting evidence for such non-optimal, strained emitter/base region is provided from x-ray (004) & (002) diffraction but mainly from cleaved edge (g=002) dark field TEM, revealing significant interfacial non-uniformity, also likely correlated to the emitter layer ordering present. PR spectral information is compared with PL lineshape data - including Arrhenius (thermal) plots, while extracted interfacial electric field data are also supported by device finite-element (ANSYS) modelling. In summary this paper demonstrates the application of non-destructive and rapid techniques for evaluation and control of compound semiconductor materials for HBT technology.

Murtagh, Martin E.; Kelly, Patrick; O'Looney, Breda; Murphy, Frank; Modreanu, Mircea

2003-03-01

15

Advanced insulated gate bipolar transistor gate drive  

DOEpatents

A gate drive for an insulated gate bipolar transistor (IGBT) includes a control and protection module coupled to a collector terminal of the IGBT, an optical communications module coupled to the control and protection module, a power supply module coupled to the control and protection module and an output power stage module with inputs coupled to the power supply module and the control and protection module, and outputs coupled to a gate terminal and an emitter terminal of the IGBT. The optical communications module is configured to send control signals to the control and protection module. The power supply module is configured to distribute inputted power to the control and protection module. The control and protection module outputs on/off, soft turn-off and/or soft turn-on signals to the output power stage module, which, in turn, supplies a current based on the signal(s) from the control and protection module for charging or discharging an input capacitance of the IGBT.

Short, James Evans (Monongahela, PA); West, Shawn Michael (West Mifflin, PA); Fabean, Robert J. (Donora, PA)

2009-08-04

16

Free electron gas primary thermometer: The bipolar junction transistor  

NASA Astrophysics Data System (ADS)

The temperature of a bipolar transistor is extracted probing its carrier energy distribution through its collector current, obtained under appropriate polarization conditions, following a rigorous mathematical method. The obtained temperature is independent of the transistor physical properties as current gain, structure (Homo-junction or hetero-junction), and geometrical parameters, resulting to be a primary thermometer. This proposition has been tested using off the shelf silicon transistors at thermal equilibrium with water at its triple point, the transistor temperature values obtained involve an uncertainty of a few milli-Kelvin. This proposition has been successfully tested in the temperature range of 77-450 K.

Mimila-Arroyo, J.

2013-11-01

17

3.0 Bipolar Junction Transistors 1 of 18 3.1 Introduction  

E-print Network

3.0 Bipolar Junction Transistors 1 of 18 3.1 Introduction 3.2 Transistor Construction 3.3 Transistor Operation The base region is very thin. Almost all of the emitter base majority carriers go all it and are swept across. #12;3.0 Bipolar Junction Transistors 2 of 18 3.4 Common-Base Configuration Notation

Allen, Gale

18

Low-frequency noise in polysilicon emitter bipolar transistors  

Microsoft Academic Search

The low-frequency noise in polysilicon emitter bipolar transistors is investigated. Transistors with various geometries and various properties of the oxide layer at the monosilicon polysilicon interface are studied. The main 1\\/f noise source proved to be located in the oxide layer. This source causes both 1\\/f noise in the base current SIb and 1\\/f noise in the emitter series resistance

H. A. W. Markus; T. G. M. Kleinpenning

1995-01-01

19

A gallium phosphide high-temperature bipolar junction transistor  

NASA Technical Reports Server (NTRS)

Preliminary results are reported on the development of a high temperature (350 C) gallium phosphide bipolar junction transistor (BJT) for geothermal and other energy applications. This four-layer p(+)n(-)pp(+) structure was formed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The initial design suffers from a series resistance problem which limits the transistor's usefulness at high temperatures.

Zipperian, T. E.; Dawson, L. R.; Chaffin, R. J.

1981-01-01

20

THz Bipolar Transistor Circuits: Technical Feasibility, Technology Development,  

E-print Network

THz Bipolar Transistor Circuits: Technical Feasibility, Technology Development, Integrated Circuit-gain cutoff frequencies of 1-3 THz. High bandwidths are obtained by scaling; the critical limits for the 64 nm scaling geneation (1 THz f, 2 THz fmax) have been developed. We here examine the high

Rodwell, Mark J. W.

21

The temperature characteristics of bipolar transistors fabricated in CMOS technology  

Microsoft Academic Search

This paper presents the results of an experimental investigation of the temperature characteristics of bipolar transistors fabricated in CMOS technology. These results have to be known and understood to enable the design of high-performance temperature sensors and bandgap references in CMOS integrated circuits. The non-idealities of proportional to the absolute temperature voltage (VPTAT) have been studied, and the results show

Guijie Wang; Gerard C. M Meijer

2000-01-01

22

Scaling of SiGe Heterojunction Bipolar Transistors  

E-print Network

-mail: freemang@us.ibm.com). Digital Object Identifier 10.1109/JPROC.2005.852228 Fig. 1. The trend of cutoff of Si technologies. Such improvement is ev- idenced by the recently reported SiGe HBTs exhibiting cutoff an overview of the per- formance trend of Si-based bipolar transistors. Fig. 1 shows accumulated data points

Rieh, Jae-Sung

23

EE 321 BJT 1 Fall 2008 Bipolar Junction Transistors, Part I  

E-print Network

EE 321 BJT 1 Fall 2008 EE321 Lab Bipolar Junction Transistors, Part I In this lab we will investigate how a bipolar junction transistor (BJT) can be used to amplify signals. 1. First, use your multimeter to measure the base-emitter and base-collector junctions of your transistor (Figure 1 and 2). When

Wedeward, Kevin

24

Current gain in bipolar transistors with a field plate over the base surface  

E-print Network

Current gain in bipolar transistors with a field plate over the base surface V. Anantharam and K.N. Bhat Indexing terms: Bipolar transistors, Analogue simulation, Carrier lifetime, Minority carriers. Abstract: Vertical n-p-n and lateral p-n-p transistor structures of an integrated circuit are studied using

Anantharam, Venkat

25

Evaluation of the Radiation Tolerance of SiGe Heterojunction Bipolar Transistors Under  

E-print Network

Evaluation of the Radiation Tolerance of SiGe Heterojunction Bipolar Transistors Under 24GeV Proton a variety of Silicon Germanium (SiGe) Heterojunction Bipolar Transistors (HBTs) manufactured by IBM has a special front transistor, chosen carefully to minimize noise and usually requiring a larger

California at Santa Cruz, University of

26

IEEE TRANSACTIONS ON ELECTRON DEVICES 1 Bipolar Charge-Plasma Transistor  

E-print Network

IEEEProof IEEE TRANSACTIONS ON ELECTRON DEVICES 1 Bipolar Charge-Plasma Transistor: A Novel Three approach for forming a lateral bipolar4 charge-plasma transistor (BCPT) is explored using 2-D simu-5-p-n transistor. Electrical characteristics of the proposed9 device are simulated and compared

Kumar, M. Jagadesh

27

Co-integrated resonant tunneling and heterojunction bipolar transistor full adder  

Microsoft Academic Search

We present the first resonant tunneling bipolar transistor integrated circuits operating at room temperature. The circuits are comprised of co-integrated resonant tunneling and double heterojunction bipolar transistors based on III-V heteroepitaxy on InP substrates. The resonant tunneling bipolar transistors exhibit a peak-to-valley collector current ratio exceeding 70 which is higher than previous room temperature reports. Using this technology we demonstrate

A. C. Seabaugh; A. H. Taddiken; J. N. Randall; Y.-C. Kao; B. Newell

1993-01-01

28

Doping To Reduce Base Resistances Of Bipolar Transistors  

NASA Technical Reports Server (NTRS)

Modified doping profile proposed to reduce base resistance of bipolar transistors. A p/p+ base-doping profile reduces base resistance without reducing current gain. Proposed low/high base-doping profile realized by such low-temperature deposition techniques as molecular-beam epitaxy, ultra-high-vacuum chemical-vapor deposition, and limited-reaction epitaxy. Produces desired doping profiles without excessive diffusion of dopant.

Lin, True-Lon

1991-01-01

29

Direct extraction of equivalent circuit parameters for heterojunction bipolar transistors  

Microsoft Academic Search

A new method is presented for the direct extraction of hybrid-T equivalent circuits for heterojunction bipolar transistors. The method differs from previous ones by extracting the equivalent circuit without using test structures or numerical optimization techniques. Instead, all equivalent circuit parameters are calculated analytically from small-signal S-parameters measured under different bias conditions. The analysis includes the distributed nature of the

Ce-Jun Wei; James C. M. Hwang

1995-01-01

30

Investigation of the tunneling emitter bipolar transistor as spin-injector into silicon  

E-print Network

In this thesis is discussed the tunneling emitter bipolar transistor as a possible spin-injector into silicon. The transistor has a metallic emitter which as a spin-injector will be a ferromagnet. Spin-polarized electrons ...

Van Veenhuizen, Marc Julien

2010-01-01

31

THZ INDIUM PHOSPHIDE BIPOLAR TRANSISTOR TECHNOLOGY M. J. W. Rodwell1  

E-print Network

THZ INDIUM PHOSPHIDE BIPOLAR TRANSISTOR TECHNOLOGY M. J. W. Rodwell1 , J. Rode1 , H.W. Chiang1 , P3 , Thousand Oaks, CA. Abstract -- Scaling laws and limits of THz indium Phosphide heterojunction bipolar transistors (HBTs) are presented. The primary limits to scaling through the 32 nm / 3 THz node

Rodwell, Mark J. W.

32

Suppression of boron transient enhanced diffusion in SiGe heterojunction bipolar transistors by carbon incorporation  

E-print Network

Suppression of boron transient enhanced diffusion in SiGe heterojunction bipolar transistors-4 Record high-frequency npn Si/Si1 xGex /Si bipolar transistor performance has been achieved by reducing postgrowth thermal process- ing or implantation and annealing due to transient enhanced diffusion TED effects

33

A New SiGe Base Lateral PNM Schottky Collector Bipolar Transistor on SOI for Non-Saturating  

E-print Network

A New SiGe Base Lateral PNM Schottky Collector Bipolar Transistor on SOI for Non-Saturating VLSI Logic Design Abstract- A novel bipolar transistor structure, namely, SiGe base lateral PNM Schottky collector bipolar transistor (SCBT) in Silicon-On-Insulator (SOI) substrate is explored using two

Kumar, M. Jagadesh

34

The equivalence of displacement damage in silicon bipolar junction transistors  

NASA Astrophysics Data System (ADS)

The current gain degradation in silicon bipolar junction transistors (BJTs) is examined under the irradiation with heavy ions. To characterize the radiation damage of the BJTs, the ionizing dose Di and displacement dose Dd verse the chip depth in the BJTs have been calculated for heavy ions. Based on the irradiation testing and calculation results, an approach to evaluate the equivalence of displacement damage in silicon BJTs is given, which could optimize the non-ionizing energy loss (NIEL) methodology and normalize the displacement damage caused by heavy ions.

Liu, Chaoming; Li, Xingji; Geng, Hongbin; Rui, Erming; Guo, Lixin; Yang, Jianqun; Xiao, Liyi

2012-06-01

35

Self-heating in high performance bipolar transistors fabricated on SOI substrates  

Microsoft Academic Search

The effects of self-heating on the characteristics of bipolar transistors fabricated on silicon-on-insulator (SOI) substrates are discussed through measurements and simulations. It is shown that the SOI substrate's buried oxide affects the thermal characteristics of the transistor. A three fold increase in thermal resistivity is observed on transistors fabricated on SOI substrates over identical transistors fabricated on regular silicon substrates.

P. R. Ganci; J.-J. J. Hajjar; T. Clark; P. Humphries; J. Lapham; D. Buss

1992-01-01

36

Bipolar junction transistor models for circuit simulation of cosmic-ray-induced soft errors  

NASA Technical Reports Server (NTRS)

This paper examines bipolar junction transistor models suitable for calculating the effects of large excursions of some of the variables determining the operation of a transistor. Both the Ebers-Moll and Gummel-Poon models are studied, and the junction and diffusion capacitances are evaluated on the basis of the latter model. The most interesting result of this analysis is that a bipolar junction transistor when struck by a cosmic particle may cause a single event upset in an electronic circuit if the transistor is operated at a low forward base-emitter bias.

Benumof, R.; Zoutendyk, J.

1984-01-01

37

Parasitic capacitance extraction in bipolar junction transistor for arbitrarily shaped diffusion  

E-print Network

PARASITIC CAPACITANCE EXTRACTION IN BIPOLAR JUNCTION TRANSISTOR FOR ARBITRARILY SHAPED DIFFUSION A Thesis by MEHEDI HASSAN Subnntted to the OIIice oi' Graduate Studies of Texas ASM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 1992 Major Subject: Electrical Engineering PARASITIC CAPACITANCE EXTRACTION IN BIPOLAR JUNCTION TRANSISTOR FOR ARBITRARILY SHAPED DIFFUSION A Thesis bv MEHEDI HASSAV Approved as to style and content by: b...

Hassan, Mehedi

2012-06-07

38

Neutron effects on the electrical and switching characteristics of NPN bipolar power transistors  

NASA Technical Reports Server (NTRS)

The use of nuclear reactors to generate electrical power for future space missions will require the electrical components used in the power conditioning, control, and transmission subsystem to operate in the associated radiation environments. An initial assessment of neutron irradiation on the electrical and switching characteristics of commercial high power NPN bipolar transistors was investigated. The results clearly show the detrimental effects caused by neutron irradiation on the electrical and switching characteristics of the NPN bipolar power transistor.

Frasca, Albert J.; Schwarze, Gene E.

1988-01-01

39

Bipolar transport in organic field-effect transistors: organic semiconductor blends versus contact modification  

Microsoft Academic Search

The achievement of bipolar transport is an important feature of organic semiconductors, both for a fundamental understanding of transport properties and for applications such as complementary electronic devices. We have investigated two routes towards organic field-effect transistors exhibiting bipolar transport characteristics. As a first step, ambipolar field-effect transistors are realized by mixtures of p-conducting copper-phthalocyanine (CuPc) and n-conducting buckminsterfullerene (C60).

Andreas Opitz; Michael Kraus; Markus Bronner; Julia Wagner; Wolfgang Brütting

2008-01-01

40

Anomaly detection of non punch through insulated gate bipolar transistors (IGBT) by robust covariance estimation techniques  

Microsoft Academic Search

The insulated gate bipolar transistor (IGBT) is a power transistor that is used in medium to high power, and low frequency applications. These applications include railway traction motors, wind turbines, electric and hybrid vehicles and uninterrupted power supplies. IGBT failures can result in reduced efficiency of the system or lead to system failure. Anomaly detection techniques can provide early warning

N. Patil; Sandeep Menon; Diganta Das; Michael Pecht

2010-01-01

41

A unified approach to RF and microwave noise parameter modeling in bipolar transistors  

Microsoft Academic Search

A unified approach to RF and microwave noise parameter modeling in bipolar transistors is presented. Circuit level noise parameters including the minimum noise figure, the optimum generator admittance, and the noise resistance are analytically linked to the fundamental noise sources and the y-parameters of the transistor through circuit analysis of the chain noisy two-port representation. Comparisons of circuit level noise

Guofu Niu; John D. Cressler; Shiming Zhang; William E. Ansley; Charles S. Webster; David L. Harame

2001-01-01

42

Superiority of common-base to common-emitter heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

Common-emitter (CE) configuration of bipolar junction transistors has been used in virtually all amplifications since the invention of transistor, whereas common-base (CB) configuration has been rarely used due to its inferior performance in comparison to CE. For heterojunction bipolar transistors (HBTs) this conviction needs to be changed. We compared the radio-frequency (rf) power handling capability of the HBT between CE and CB configurations and analyzed their amplification mechanisms. It is found that CB HBT significantly outperforms CE HBT under proper bias conditions, revealing the significant superiority of CB to CE configuration of HBTs for rf power amplification.

Qin, Guoxuan; Wang, Guogong; McCaughan, Leon; Ma, Zhenqiang

2010-09-01

43

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 48, NO. 11, NOVEMBER 2001 2455 Bipolar Transistor Technology: Past and Future  

E-print Network

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 48, NO. 11, NOVEMBER 2001 2455 Bipolar Transistor transistor. The emergence of the transistor from Bell Laboratories in late 1947 and early 1948 was the first step in the development of today's semiconductor electronics industry. Currently transistor production

Rodwell, Mark J. W.

44

InGaAsN/AlGaAs Pnp Heterojunction Bipolar Transistor  

SciTech Connect

The authors have demonstrated a functional Pnp heterojunction bipolar transistor (HBT) using InGaAsN. The metalorganic vapor phase epitaxy (MOCVD) grown Al{sub 0.3}Ga{sub 0.7}As/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} HBT takes advantage of the narrower bandgap energy (E{sub g} = 1.25eV) of In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01}, which is lattice matched to GaAs. Compared with the Al{sub 0.3}Ga{sub 0.7}As/GaAs material system, the Al{sub 0.3}Ga{sub 0.7}As/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} material system has a larger conduction band offset, while the valence band offset remains comparable. This characteristic band alignment is very suitable for Pnp HBT applications. The device's peak current gain is 23 and it has a turn on voltage of 0.77V, which is 0.25V lower than in a comparable Pnp Al{sub 0.3}Ga{sub 0.7}As/GaAs HBT.

BACA,ALBERT G.; CHANG,PING-CHIH; HOU,H.Q.; LAROCHE,J.R.; LI,N.Y.; REN,F.; SHARPS,P.R.

1999-11-03

45

Neutron Radiation Effect On 2N2222 And NTE 123 NPN Silicon Bipolar Junction Transistors  

NASA Astrophysics Data System (ADS)

This paper examines neutron radiation with PTS (Pneumatic Transfer System) effect on silicon NPN bipolar junction transistors (2N2222 and NTE 123) and analysis of the transistors in terms of electrical characterization such as current gain after neutron radiation. The key parameters are measured with Keithley 4200SCS. Experiment results show that the current gain degradation of the transistors is very sensitive to neutron radiation. The neutron radiation can cause displacement damage in the bulk layer of the transistor structure. The current degradation is believed to be governed by increasing recombination current between the base and emitter depletion region.

Oo, Myo Min; Rashid, N. K. A. Md; Karim, J. Abdul; Zin, M. R. Mohamed; Hasbullah, N. F.

2013-12-01

46

Proposal and design of a new SiC-emitter lateral NPM Schottky collector bipolar transistor on  

E-print Network

Proposal and design of a new SiC-emitter lateral NPM Schottky collector bipolar transistor on SOI of SiC [4­7], opened up new opportunities for device designers to use SiC as an emitter of BJT, for the first time, we propose a new SiC emitter lateral NPM Schottky collector bipolar transistor for obtaining

Kumar, M. Jagadesh

47

\\\\Proc. IEEE 2004 Int. Conference on MicroelectronicTest Structures, Vol 17, March 2004. 127 A New Test Circuit for the Matching Characterization of npn Bipolar Transistors  

E-print Network

.3 A New Test Circuit for the Matching Characterization of npn Bipolar Transistors Jan Einfeld", Ulrich is presented for the mismatch characterization of npn bipolar transistors. The macro contains a CMOS circuit a force/sense method is employed to assure the high voltage accuracy requested for bipolar transistors

McNeill, John A.

48

Neutron irradiation effects on AlGaAs/GaAs heterojunction bipolar transistors  

SciTech Connect

AlGaAs/GaAs heterojunction bipolar transistors irradiated with 10/sup 15/ neutrons/cm/sup 2/ demonstrated superior performance to silicon bipolar transistors. The post neutron current gain was dominated by recombination in the emitter-base depletion region. The base current exhibited an ideality factor n > 2 after irradiation, which was attributed to two possible recombination mechanisms associated with neutron induced traps: tunneling-assisted trapping and recombination arising from a nonuniform distribution of Shockley-Read-Hall centers within the depletion region. The emitter-base heterojunction was degraded more than the collector-base homojunction after irradiation.

Schrantz, G.A.; Van Vonno, N.W.; Krull, W.A.; Rao, M.A.; Long, S.T.; Kroemer, H.

1988-12-01

49

Degradation of silicon bipolar junction transistors at high forward current densities  

Microsoft Academic Search

The physical degradation mechanisms of silicon bipolar function transistors at high forward current densities were delineated quantitatively using three n\\/p\\/p and one p\\/n\\/p state-of-the-art submicron polysilicon-emitter transistor technologies. The increase of the operating current gain and decrease of emitter series resistance from million-ampere per square centimeter stress current are related to hydrogenation of the electronic traps at the metal-silicide\\/polycrystalline-Si and

Michael S. Carroll; Arnost Neugroschel; Chih-Tang Sah

1997-01-01

50

A high current gain 4H-SiC NPN power bipolar junction transistor  

Microsoft Academic Search

This work reports the development of high power 4H-SiC bipolar junction transistors (BJTs) by using reduced implantation dose for p+ base contact region and annealing in nitric oxide of base-to-emitter junction passivation oxide for 2 hours at 1150°C. The transistor blocks larger than 480 V and conducts 2.1 A (Jc=239 A\\/cm2) at Vce=3.4 V, corresponding to a specific on-resistance (Rsp

Jianhui Zhang; Yanbin Luo; Petre Alexandrov; Leonid Fursin; Jian H. Zhao

2003-01-01

51

Abstract --Design guidelines are provided to improve the thermal stability of three-finger bipolar transistors. Experiments  

E-print Network

transistors. Experiments and simulations are conducted on silicon-on-glass BJTs varying the topography junction transistor, heatspreaders, multifinger device, silicon-on-glass. I. INTRODUCTION In many circuit applications, transistors have to be designed to handle an appreciable amount of current. In bipolar junction

Technische Universiteit Delft

52

1070 IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 49, NO. 6, JUNE 2002 A New Lateral PNM Schottky Collector Bipolar Transistor  

E-print Network

Collector Bipolar Transistor (SCBT) on SOI for Nonsaturating VLSI Logic Design M. Jagadesh Kumar and D transistor (SCBT) on silicon-on-insulator (SOI) are explored using two-dimensional (2-D) simulation. The collector-base junction of the proposed lateral PNM transistor consists of a Schottky junction between n

Kumar, M. Jagadesh

53

Analysis of long-term ionizing radiation effects in bipolar transistors  

Microsoft Academic Search

The ionizing radiation effects of electrons on bipolar transistors have been analyzed using the data base from the Voyager project. The data were subjected to statistical analysis, leading to a quantitative characterization of the product and to data on confidence limits which will be useful for circuit design purposes. These newly-developed methods may form the basis for a radiation hardness

A. G. Stanley; K. E. Martin

1978-01-01

54

Realizing high-voltage thin film lateral bipolar transistors on SOI with a collector-tub  

E-print Network

Deb Roy and M. Jagadesh Kumar Department of Electrical Engineering, Indian Institute of Technology to improve the breakdown voltage of BJTs fabricated on SOI. Design/methodology/approach ­ We have used two Bipolar transistors, Breakdown voltage, Simulation Paper type Research paper 1. Introduction Thin film

Kumar, M. Jagadesh

55

A thermionic-emission-diffusion model for graded base Pnp heterojunction bipolar transistors  

E-print Network

A thermionic-emission-diffusion model for graded base Pnp heterojunction bipolar transistors S An analytical model which matches thermionic-emission-diffusion of holes across the emitter-base heterojunction-base space charge region is shown to be of comparable importance to thermionic emission in controlling hole

Cahay, Marc

56

Low frequency (1\\/f ) noise model for the base current in polysilicon emitter bipolar junction transistors  

Microsoft Academic Search

A new model for the low frequency (LF) noise in the base current of polysilicon emitter bipolar junction transistors (BJTs) is proposed. This model is based on the carrier number fluctuation approach and satisfactorily accounts for the base current noise characteristics. The base current fluctuations are ascribed to surface and volume noise sources. The surface noise arises from the low

A. Mounib; G. Ghibaudo; F. Balestra; D. Pogany; A. Chantre; J. Chroboczek

1996-01-01

57

Measurements and comparison of low frequency noise in npn and pnp polysilicon emitter bipolar junction transistors  

E-print Network

bipolar transistors.1­15 A review of some of the literature on low frequency noise in npn tran- sistors.1, in which case, it is referred to as 1/f noise. However, there are reports of values greater than 1 was given in Ref. 10. However, all these articles and their references report on low frequency noise only

Bashir, Rashid

58

A new parameter extraction technique for small-signal equivalent circuit of polysilicon emitter bipolar transistors  

Microsoft Academic Search

We propose a new parameter extraction method for advanced polysilicon emitter bipolar transistors. This method is based on the predetermination of equivalent circuit parameters using the analytical expressions of de-embedded Z-parameters of these devices. These parameter values are used as initial values for the parameter extraction process using optimization. The entire device equivalent circuit, containing RF probe pad and interconnection

Seonghearn Lee; Byung R. Ryum; Sang Won Kang

1994-01-01

59

Impact of emitter resistance mismatch on base and collector current matching in bipolar transistors  

E-print Network

Impact of emitter resistance mismatch on base and collector current matching in bipolar transistors of emitter resistance mismatch on base and collector current matching at high current. To this end, we simulate base and collector mismatch thanks to the experimental values of emitter access resistance and its

McNeill, John A.

60

Switching Characteristics of a 4H-SiC Based Bipolar Junction Transistor to 200 C.  

National Technical Information Service (NTIS)

Static curves and resistive load switching characteristics of a 600 V, 4 A rated, SiC-based NPN bipolar power transistor (BJT) were observed at selected temperatures from room to 200 C. All testing was done in a pulse mode at low duty cycle (approx. 0.1 p...

J. M. Niedra

2006-01-01

61

High current gain 4H-SiC npn bipolar junction transistors  

Microsoft Academic Search

The authors report a common emitter current gain ? of 55 in npn epitaxial-emitter 4H-SiC bipolar junction transistors. The spacing between the p+ base contact implant and the edge of the emitter finger is critical in obtaining high-current gain. VCEO of these devices is 500 V, and VCBO is 700 V.

Chih-Fang Huang; James A. Cooper

2003-01-01

62

Realising wide bandgap P-SiC-emitter lateral heterojunction bipolar transistors with low  

E-print Network

model of 4H SiC due its availability compared to that of 3C SiC. We will also demonstrate that the useRealising wide bandgap P-SiC-emitter lateral heterojunction bipolar transistors with low collector of the wide bandgap SiC-P-emitter lateral HBTs using a dual-bandgap emitter. In their approach, the collector

Kumar, M. Jagadesh

63

300 Degree C GaN/AlGaN Heterojunction Bipolar Transistor  

SciTech Connect

A GaN/AIGaN heterojunction bipolar transistor has been fabricated using C12/Ar dry etching for mesa formation. As the hole concentration increases due to more efficient ionization of the Mg acceptors at elevated temperatures (> 250oC), the device shows improved gain. Future efforts which are briefly summarized. should focus on methods for reducing base resistance.

Abernathy, C.R.; Baca, A.G.; Cho, H.; Chow, P.P.; Han, J.; Hichman, R.A.; Jung, K.B.; Kopf, R.F.; La Roche, J.R.; Pearton, S.J.; Ren, F.; Shul, R.J.; Van Hove, J.M.; Wilson, R.G.

1998-10-14

64

Le transistor effet de champ grille Schottky au GaAs : analyse et modle mathmatique du fonctionnement  

E-print Network

303 Le transistor à effet de champ à grille Schottky au GaAs : analyse et modèle mathématique du théorique et expérimentale, en régime statique, du comportement du transistor à effet de champ à l du transistor, lorsque la grille est distribuée suivant la longueur L de grille, est établi et permet

Paris-Sud XI, Université de

65

Abstract--Basic SiC bipolar transistors have been studied in the past for their applications where high power or high  

E-print Network

Abstract--Basic SiC bipolar transistors have been studied in the past for their applications where transistors is very low and therefore, a large base drive is required in high current applications. Therefore, it is important to enhance the current gain of SiC bipolar transistors. Using two dimensional mixed mode device

Kumar, M. Jagadesh

66

A Performance Trade-Off for the Insulated Gate Bipolar Transistor: Buffer Layer Versus Base Lifetime Reduction  

Microsoft Academic Search

A one-dimensional analytic model for the insulated gate bipolar transistor (IGBT), which includes a high-doped buffer layer in the low-doped bipolar transistor base, is developed. The model is used to perform a theoretical trade-off study between IGBT's with and without the buffer layer. The study is performed for devices of equal breakdown voltages, and the critical parameters chosen to ``trade-off''

David L. Blackburn

1987-01-01

67

On the impurity profiles of down scaled bipolar transistors  

Microsoft Academic Search

This paper presents the design and reliability issues unique to the scaled bipolar devices, which are caused by the close proximity of the heavily doped emitter and extrinsic base region and by the contradicting heat cycle requirement for the extrinsic base and intrinsic base. Issues related to the premature punchthrough, leakage around the emitter perimeter, long-term current gain degradation and

D. D. Tang; G. P. Li; C. T. Chuang; T. H. Ning

1986-01-01

68

Monolithic barrier-all-around high electron mobility transistor with planar GaAs nanowire channel.  

PubMed

High-quality growth of planar GaAs nanowires (NWs) with widths as small as 35 nm is realized by comprehensively mapping the parameter space of group III flow, V/III ratio, and temperature as the size of the NWs scales down. Using a growth mode modulation scheme for the NW and thin film barrier layers, monolithically integrated AlGaAs barrier-all-around planar GaAs NW high electron mobility transistors (NW-HEMTs) are achieved. The peak extrinsic transconductance, drive current, and effective electron velocity are 550 ?S/?m, 435 ?A/?m, and ~2.9 × 10(7) cm/s, respectively, at 2 V supply voltage with a gate length of 120 nm. The excellent DC performance demonstrated here shows the potential of this bottom-up planar NW technology for low-power high-speed very-large-scale-integration (VLSI) circuits. PMID:23635023

Miao, Xin; Zhang, Chen; Li, Xiuling

2013-06-12

69

Application of insulated gate bipolar transistor to zero-current switching converters  

Microsoft Academic Search

The problems associated with insulated-gate bipolar transistor (IGBT) devices in PWM converters, such as turn-off current tailing and turn-off latching, are largely avoided in zero-current switching resonant converters. Phenomena induced by dv\\/dt, such as the power losses and latching, are identified as the predominant problems in using IGBT devices for very-high-frequency resonant operations. The discussion and the verification of the

R. Rangan; DAN Y. CHEN; Jian Yang; JOHN LEE

1989-01-01

70

An investigation of the drive circuit requirements for the power insulated gate bipolar transistor (IGBT)  

Microsoft Academic Search

The drive circuit requirements of the insulated gate bipolar transistor (IGBT) are explained with the aid of an analytical model. It is shown that nonquasi-static effects limit the influence of the drive circuit on the time rate-of-change of anode voltage. Model results are compared with measured turn-on and turn-off waveforms for different drive, load, and feedback circuits, and for different

1991-01-01

71

An improved understanding for the transient operation of the power insulated gate bipolar transistor (IGBT)  

Microsoft Academic Search

It is shown that a nonquasi-static analysis must be used to describe the transient current and voltage waveforms of the insulated gate bipolar transistor. The nonquasi-static analysis is necessary because the transport of electrons and holes are coupled for the low-gain, high-level injection conditions, and the quasi-neutral base width changes faster than the base transit speed for typical load circuit

1990-01-01

72

Radiation Effects on Bipolar and MOS Transistors Made in Bicmos Technology  

NASA Astrophysics Data System (ADS)

Bipolar transistors were irradiated by neutrons, ions, or by both of them. Fast neutrons, as well as other types of particles, produce defects, mainly by displacing silicon atoms from their lattice positions to interstitial locations, i.e. generating vacancy-interstitial pairs, the so-called Frenkel pairs. The experimental results indicate that the gain variation is linearly related to the non-ionizing energy loss (NIEL) deposition for both neutrons and incoming ions.

Codegoni, D.; Croitoru, N.; D'Angelo, P.; Fallica, G.; Favalli, A.; Leonardi, S.; Modica, R.; Rancoita, P. G.; Seidman, A.

2004-07-01

73

75GHz fT SiGe-base heterojunction bipolar transistors  

Microsoft Academic Search

The fabrication of silicon heterojunction bipolar transistors which have a record unity-current-gain cutoff frequency (fT) of 75 GHz for a collector-base bias of 1 V, an intrinsic base sheet resistance (Rbi) of 17 k?\\/□, and an emitter width of 0.9 ?m is discussed. This performance level, which represents an increase by almost a factor of 2 in the speed of

GARY L. PATTON; JAMES H. COMFORT; BERNARD S. MEYERSON; E. F. Crabbe; G. J. Scilla; E. de Fresart; J. M. C. Stork; J. Y.-C. Sun; D. L. Harame; J. N. Burghartz

1990-01-01

74

On the thermionic-diffusion theory of minority transport in heterostructure bipolar transistors  

Microsoft Academic Search

The theory of the minority-carrier transport in heterostructure bipolar transistors (HBT) is reconsidered with a particular emphasis on the difference between the cases of abrupt and graded emitter-base junctions and the role in the former case of the quasi-Fermi level discontinuity at the interface. Exact analytical formulas are derived for the current-voltage characteristics of a double-heterojunction HBT, valid for arbitrary

Anatoly A. Grinberg; Serge Luryi

1993-01-01

75

Analysis of bipolar junction transistors with a Gaussian base-dopant impurity-concentration profile  

Microsoft Academic Search

A method for a quantitative charge-control analysis of bipolar base-junction transistors with a Gaussian dopant impurity-concentration profile is demonstrated. Analytical expressions for the base transit time are given for two different Gaussian impurity-concentration profiles with the peak concentration at the edge, and within the quasi-neutral base layer. It is also shown that approximating the Gaussian profile by a simple exponential

Guoxin Li; A. Neugroschel; Chih-Tang Sah; D. Hemmenway; T. Rivoli; J. Maddux

2001-01-01

76

Degradation of bipolar transistor current gain by hot holes during reverse emitter-base bias stress  

Microsoft Academic Search

Experimental evidences are given which demonstrate that degradation of the common-emitter forward current gain hFE of submicron silicon npn bipolar transistors at low reverse emitter-base junction applied voltage is caused by primary hot holes of the n+ \\/p emitter tunneling current rather than secondary hot electrons generated by the hot holes or thermally-generated hot electrons. Experiments also showed similar kinetic

Arnost Neugroschel; Chih-Tang Sah; Michael S. Carroll

1996-01-01

77

An implanted-emitter 4H-SiC bipolar transistor with high current gain  

Microsoft Academic Search

An epi-base, implanted-emitter, npn bipolar transistor which showed a maximum common emitter current gain (?) of ~40, the highest current gain reported for BJT in any polytype of SiC has been experimentally demonstrated in 4H-SiC. The forward drop was ~1 V at forward current density of 50 A\\/cm2. The current gain decreases hence specific on-resistance increases with increasing temperature. The

Yi Tang; Jefferey B. Fedison; T. Paul Chow

2001-01-01

78

New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET)  

E-print Network

New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET) without PN. In this paper, we propose a novel Schottky-gate BMFET (SBMFET) using P- type 4H Silicon-Carbide 13,41, a wide for the first time that the P-SiC Schottky-gate BMFET has very low ON voltage drop, good output characteristics

Kumar, M. Jagadesh

79

4 kV 4H-SiC epitaxial emitter bipolar junction transistors  

Microsoft Academic Search

In this paper, we present 4H-SiC bipolar junction transistors (BJTs) with open-base blocking voltage (BVCEO) of 4000 V, specific on-resistance (Ron,sp) of 56 m?-cm2, and common-emitter current gain ??9. These devices are designed with interdigitated base and emitter fingers with multiple emitter stripes. We assess the impact of design (emitter stripe width and contact spacing) on device performance and also

Santhosh Balachandran; T. P. Chow; A. Agarwal; C. Scozzie; K. A. Jones

2005-01-01

80

Hardness assurance testing of bipolar junction transistors at elevated irradiation temperatures  

Microsoft Academic Search

The effect of dose rate on radiation-induced current gain degradation was quantified for radiation-hardened poly-Si emitter n-p-n bipolar transistors over the range of 0.005 to 294 rad(Si)\\/s. Degradation increases sharply with decreasing dose rate and saturates near 0.005 rad(Si)\\/s. The amount of degradation enhancement at low dose rates decreases monotonically with total dose. In addition, the effect of ambient temperature

S. C. Witczakl; R. D. Schrimpfz; D. M. Fleetwood; K. F. Galloway; R. C. Lacoel; D. C. Mayer; J. M. Puhl; R. L. Pease; J. S. Suehle

1997-01-01

81

Degradation of InGaAs\\/InP double heterojunction bipolar transistors under electron irradiation  

Microsoft Academic Search

The dc characteristics of InGaAs\\/InP double heterojunction bipolar transistors (DHBTs) are studied under high-energy (~1 MeV) electron irradiation up to a fluence of 14.8×1015 electrons\\/cm 2. The devices show an increase in common-emitter current gain (hfe) at low levels of dose (<1015 electrons\\/cm2) and a gradual decrease in hfe and an increase in output conductance for higher doses. The decrease

A. Bandyopadhyay; S. Subramanian; S. Chandrasekhar; Andrew G. Dentai; Stephen M. Goodnick

1999-01-01

82

2.5 W CW X-band heterojunction bipolar transistor  

Microsoft Academic Search

A 2.43-W CW (continuous wave) output power was obtained with AlGaAs-GaAs heterojunction bipolar transistors at 10 GHz with 5.8-dB gain and 30% power-added efficiency using 2-?m minimum-geometry devices. The device design and fabrication techniques were improved to maintain high power density (>3 W\\/mm of emitter length) operation as the device size is increased. Accurate device models were developed both for

B. Bayraktaroglu; R. D. Hudgens; M. A. Khatibzadeh; H. Q. Tserng

1989-01-01

83

Investigation and application of neutron damage to bipolar transistors in light water reactor dosimetry  

SciTech Connect

A method of fast neutron metrology and a basis for prediction of changes in performance parameters of semiconductor devices in power plant radiation environments has been established using Cf-252 sources. Three general purpose NPN bipolar transistors (PN2222A, ECG-196, and ECG-184) were chosen as the neutron damage monitors and the change in inverse d.c. current gain before and after irradiation was chosen as the damage parameter for the measurement. The main findings of the investigation were as follows: the change in inverse d.c. current gain for PN2222A transistors was approximately a linear function of the neutron fluence up to 2.0E15 n(1MeV)/cm/sup 2/. The concept of 1-MeV equivalent neutron fluence which characterizes an incident energy-fluence spectrum in terms of the fluence of monoenergetic neutrons at 1 MeV, is in error for application to common transistors in a typical power plant environment. Finally, the normalized damage coefficient which is the ratio of damage to 1-MeV equivalent neutron fluence divided by the measured base transit time of individual transistors, for all three types of transistors is nearly the same with an average value of 1.27E - 7 +/- 15.0% cm/sup 2//m(1 MeV).Sec.

Roknizadeh, M.

1987-01-01

84

A scalable high-frequency noise model for bipolar transistors with application to optimal transistor sizing for low-noise amplifier design  

Microsoft Academic Search

Fully scalable, analytical HF noise parameter equations for bipolar transistors are presented and experimentally tested on high-speed Si and SiGe technologies. A technique for extracting the complete set of transistor noise parameters from Y parameter measurements only is developed and verified. Finally, the noise equations are coupled with scalable variants of the HICUM and SPICE-Gummel-Poon models and are employed in

Sorin P. Voinigescu; Michael C. Maliepaard; Jonathan L. Showell; Greg E. Babcock; David Marchesan; Michael Schroter; Peter Schvan; David L. Harame

1997-01-01

85

'Downsized' bipolar fires 20-GHz oscillator  

NASA Astrophysics Data System (ADS)

Technological developments in the field of small-scale silicon bipolar transistors are reviewed. Attention is given to experiments carried out at one company to enhance the performance of a downscaled bipolar transistor at frequencies beyond 20 GHz. Performance was evaluated during tests in fundamental frequency YIG-tuned oscillators. The techniques used to construct the transistors are described, and S-parameter measurements were made with the transistors die-attached to ceramic chipcarriers and bonded in a common emitter configuration using 0.7-mil gold wire. Typical results were obtained for a transistor design biased at a collector-emitter voltage of 10 VDC and an emitter current of 20 mA. The maximum available gain of the bipolar transistors was 21.8 dB at 2 GHz and 15.7 dB at 4 GHz. The maximum unilaterial gain was 6 dB at 18 GHz. The spurious signal output of YIG-tuned bipolar oscillators was found to be lower than that of GaAs FET oscillators over the -54 to 100 C temperature range. The possibility of improving oscillator performance by combining a bipolar oscillator with wideband distributed GaAs MMIC amplifiers is considered.

Leung, C. C.; Snapp, C. P.; Grande, V. J.

1985-09-01

86

The pulsed microwave damage trend of a bipolar transistor as a function of pulse parameters  

NASA Astrophysics Data System (ADS)

In the present paper we conduct a theoretical study of the thermal accumulation effect of a typical bipolar transistor caused by high power pulsed microwaves (HPMs), and investigate the thermal accumulation effect as a function of pulse repetition frequency (PRF) and duty cycle. A study of the damage mechanism of the device is carried out from the variation analysis of the distribution of the electric field and the current density. The result shows that the accumulation temperature increases with PRF increasing and the threshold for the transistor is about 2 kHz. The response of the peak temperature induced by the injected single pulses indicates that the falling time is much longer than the rising time. Adopting the fitting method, the relationship between the peak temperature and the time during the rising edge and that between the peak temperature and the time during the falling edge are obtained. Moreover, the accumulation temperature decreases with duty cycle increasing for a certain mean power.

Ma, Zhen-Yang; Chai, Chang-Chun; Ren, Xing-Rong; Yang, Yin-Tang; Zhao, Ying-Bo; Qiao, Li-Ping

2013-02-01

87

An ultrasonic-switching three phase current source inverter with insulated gate bipolar transistors  

NASA Astrophysics Data System (ADS)

Insulated Gate Bipolar Transistor (IGBT) were applied in ultrasonic switching current source inverters for power purposes. The current source inverter is supplied by a current mode controlled chopper. Both parts, the inverter as well as the chopper consist of IGBT which enable the use of a 20 kHz switching frequency. The current source inverter is controlled by using a periodic switching pattern, generated by a partly free-programmable control systems consisting of a computer and a controllable external memory containing several tables of switching patterns. An output power of 4 kW is attained, demonstrating the applicability of IGBT in ultrasonic switching current source inverters for power purposes.

Blom, A. C.

1989-08-01

88

Surface Leakage in GaN\\/InGaN Double Heterojunction Bipolar Transistors  

Microsoft Academic Search

We report a study on the surface-leakage current in GaN\\/InGaN double heterojunction bipolar transistors (DHBTs) that are grown on a sapphire substrate. Surface-leakage-current densities on an unpassivated DHBT are 9.6 times 10-5 - 5.8 times 10-4 A\\/cm for JC = 0.5-50 A\\/cm2. A fabricated n-p-n GaN\\/InGaN DHBT shows the common-emitter dc current gain of 42, the collector-current density of 5.2

Shyh-Chiang Shen; Yi-Che Lee; Hee-Jin Kim; Yun Zhang; Suk Choi; Russell D. Dupuis; Jae-Hyun Ryou

2009-01-01

89

On the effects of hot carriers on the RF characteristics of Si\\/SiGe heterojunction bipolar transistors  

Microsoft Academic Search

This work for the first time experimentally investigates the hot carrier effects on the RF characteristics (up to 30 GHz) of Si\\/SiGe heterojunction bipolar transistors (HBT's). Reverse base-emitter voltage stresses were applied at room temperature on BiCMOS compatible, sub-micron transistors. The main observed degradation is a decrease of S 21. It was found that this degradation is minimized (maximized) when

M. Borgarino; J. G. Tartarin; J. Kuchenbecker; T. Parra; H. Lafontaine; T. Kovacic; R. Plana; J. Graffeuil

2000-01-01

90

Urea biosensor based on an extended-base bipolar junction transistor.  

PubMed

In this study, a urea biosensor was prepared by the immobilization of urease onto the sensitive membrane of an extended-base bipolar junction transistor. The pH variation was used to detect the concentration of urea. The SnO2/ITO glass, fabricated by sputtering SnO2 on the conductive ITO glass, was used as a pH-sensitive membrane, which was connected with a commercial bipolar junction transistor device. The gels, fabricated by the poly vinyl alcohol with pendent styrylpyridinium groups, were used to immobilize the urease. This readout circuit, fabricated in a 0.35-um CMOS 2P4M process, operated at 3.3V supply voltage. This circuit occupied an area of 1.0 mm × 0.9 mm. The dynamic range of the urea biosensor was from 1.4 to 64 mg/dl at the 10 mM phosphate buffer solution and the sensitivity of this range was about 65.8 mV/pUrea. The effect of urea biosensors with different pH values was considered, and the characteristics of urea biosensors based on EBBJT were described. PMID:24211878

Sun, Tai-Ping; Shieh, Hsiu-Li; Liu, Chun-Lin; Chen, Chung-Yuan

2014-01-01

91

Emitter ballasting resistor design for, and current handling capability of AlGaAs\\/GaAs power heterojunction bipolar transistors  

Microsoft Academic Search

A systematic investigation of the emitter ballasting resistor for power heterojunction bipolar transistors (HBTs) is presented. The current handling capability of power HBTs is found to improve with ballasting resistance. An equation for the optimal ballasting resistance is presented, where the effects of thermal conductivity of the substrate material and the temperature coefficient of the ballasting resistor are taken into

Guang-bo Gao; M. Selim Unlu; H. Morkoc; D. L. Blackburn

1991-01-01

92

Device operation of InGaN heterojunction bipolar transistors with a graded emitter-base design  

E-print Network

Device operation of InGaN heterojunction bipolar transistors with a graded emitter-base design TGaN emitter-base design grown by metal organic chemical vapor deposition on sapphire substrates is demonstrated. The Gummel plot, current gain, and common-emitter current-voltage characteristics of the device

Asbeck, Peter M.

93

Reduction method for low-frequency noise of GaAs junction field-effect transistor at a cryogenic temperature  

NASA Astrophysics Data System (ADS)

A GaAs junction field-effect transistor (JFET) is a promising candidate for low-frequency, low-noise, and low-power cryogenic electronics to read out high-impedance photodetectors. We report on the spectral noise characteristics of a SONY n-type GaAs JFET, operating at the depression mode, at a cryogenic temperature of 4.2 K. If the GaAs JFET is turned on at 4.2 K, a random telegraph signal (RTS) is found to be the dominant noise source at low frequencies. However, the switching rate of RTS can be drastically reduced if the GaAs JFET is heated up to 55 K and cooled down again to 4.2 K while keeping the same drain current flow. We refer to this phenomenon as the thermal cure (TC). With TC, low-frequency noise can be reduced to below 1 ?V/Hz1/2 at 1 Hz. The critical temperature for TC is found to be ˜35 K for our GaAs JFET.

Fujiwara, M.; Sasaki, M.; Akiba, M.

2002-03-01

94

Electrical properties of the InP/InGaAs pnp heterostructure-emitter bipolar transistor  

SciTech Connect

The dc performances of an InP/InGaAs pnp heterostructure-emitter bipolar transistor are investigated by theoretical analysis and experimental results. Though the valence band discontinuity at the InP/InGaAs heterojunction is relatively large, the addition of a heavily-doped as well as thin p{sup +}-InGaAs emitter layer between p-InP confinement and n{sup +}-InGaAs base layers effectively eliminates the potential spike at emitter-base junction and simultaneously lowers the emitter-collector offset voltage and increases the potential barrier for electrons. Experimentally, a high current gain of 88 and a low offset voltage of 54 mV have been achieved.

Tsai, J. H. [National Kaohsiung Normal University, Department of Electronic Engineering (China)], E-mail: jhtsai@nknucc.nknu.edu.tw; Liu, W. Ch. [National Cheng-Kung University, Institute of Microelectronics, Department of Electrical Engineering (China); Guo, D. F. [Air Force Academy, Department of Electronic Engineering (China); Kang, Y. Ch. [National Kaohsiung Normal University, Department of Electronic Engineering (China); Chiu, Sh. Y.; Lour, W. Sh. [National Taiwan Ocean University, Department of Electrical Engineering (China)

2008-03-15

95

Microwave characterization and modeling of GaAs/AlGaAs heterojunction bipolar transistors  

NASA Technical Reports Server (NTRS)

The characterization and modeling of a microwave GaAs/AlGaAs heterojunction Bipolar Transistor (HBT) are discussed. The de-embedded scattering parameters are used to derive a small signal lumped element equivalent circuit model using EEsof's Touchstone software package. Each element in the equivalent circuit model is shown to have its origin within the device. The model shows good agreement between the measured and modeled scattering parameters over a wide range of bias currents. Further, the MAG (maximum available power gain) and the h sub 21 (current gain) calculated from the measured data and those predicted by the model are also in good agreement. Consequently, the model should also be capable of predicting the f sub max and the f sub T of other HBTs.

Simons, Rainee N.; Romanofsky, Robert R.

1987-01-01

96

Cryogenically cooled broad-band GaAs field-effect transistor preamplifier  

SciTech Connect

The Antiproton Source of the Fermi National Accelerator Laboratory will be capable of accumulating a total of 4.3 x 10/sup 11/ antiprotons in four hours when a wide-band feedback system for stochastic beam cooling is used. The feedback system detects and corrects at every revolution, the statistical fluctuations of the beam position and momentum. One of the essential components of such a system is a low-noise broad-band preamplifier. Acryogenically cooled 1 to 2 GHz low-noise broad-band prototype preamplifier utilizing GaAs field-effect transistors is described for this application. The preamplifier has an average gain of 30 dB and 35 dB at ambient temperatures of 293/sup 0/K and 18/sup 0/K, respectively. The noise figure has a minimum value of 0.75 dB at 300/sup 0/K and 0.24 dB at 18/sup 0/K. The optimum preamplifier operating conditions for a minimum noise figure at temperatures of 293/sup 0/K, 80/sup 0/K and 18/sup 0/K are given and are discussed. Also, the phase-shift characteristics, the input and output voltage standing-wave ratio as a function of frequency and intermodulation products content as a function of the input power level were measured.

Lo, C.C.; Leskovar, B.

1983-10-01

97

Effects of microwave pulse-width damage on a bipolar transistor  

NASA Astrophysics Data System (ADS)

This paper presents a theoretical study of the pulse-width effects on the damage process of a typical bipolar transistor caused by high power microwaves (HPMs) through the injection approach. The dependences of the microwave damage power, P, and the absorbed energy, E, required to cause the device failure on the pulse width ? are obtained in the nanosecond region by utilizing the curve fitting method. A comparison of the microwave pulse damage data and the existing dc pulse damage data for the same transistor is carried out. By means of a two-dimensional simulator, ISE-TCAD, the internal damage processes of the device caused by microwave voltage signals and dc pulse voltage signals are analyzed comparatively. The simulation results suggest that the temperature-rising positions of the device induced by the microwaves in the negative and positive half periods are different, while only one hot spot exists under the injection of dc pulses. The results demonstrate that the microwave damage power threshold and the absorbed energy must exceed the dc pulse power threshold and the absorbed energy, respectively. The dc pulse damage data may be useful as a lower bound for microwave pulse damage data.

Ma, Zhen-Yang; Chai, Chang-Chun; Ren, Xing-Rong; Yang, Yin-Tang; Chen, Bin; Zhao, Ying-Bo

2012-05-01

98

Simulation of neutron displacement damage in bipolar junction transistors using high-energy heavy ion beams.  

SciTech Connect

Electronic components such as bipolar junction transistors (BJTs) are damaged when they are exposed to radiation and, as a result, their performance can significantly degrade. In certain environments the radiation consists of short, high flux pulses of neutrons. Electronics components have traditionally been tested against short neutron pulses in pulsed nuclear reactors. These reactors are becoming less and less available; many of them were shut down permanently in the past few years. Therefore, new methods using radiation sources other than pulsed nuclear reactors needed to be developed. Neutrons affect semiconductors such as Si by causing atomic displacements of Si atoms. The recoiled Si atom creates a collision cascade which leads to displacements in Si. Since heavy ions create similar cascades in Si we can use them to create similar damage to what neutrons create. This LDRD successfully developed a new technique using easily available particle accelerators to provide an alternative to pulsed nuclear reactors to study the displacement damage and subsequent transient annealing that occurs in various transistor devices and potentially qualify them against radiation effects caused by pulsed neutrons.

Doyle, Barney Lee; Buller, Daniel L.; Hjalmarson, Harold Paul; Fleming, Robert M; Bielejec, Edward Salvador; Vizkelethy, Gyorgy

2006-12-01

99

Note: cryogenic low-noise dc-coupled wideband differential amplifier based on SiGe heterojunction bipolar transistors.  

PubMed

Silicon-germanium heterojunction bipolar transistors can be used to construct low-noise cryogenic amplifiers. We present a dc-coupled differential amplifier capable of operating down to 10 K. In this temperature regime it has bandwidth of 15 MHz and noise temperature as low as 1.3 K. When operated at liquid nitrogen temperature of 77 K, the measured noise temperature is lower than 3 K. The amplifier is based on the commercially available transistors NESG3031 and operational amplifier OPA836 and is capable of standalone operation without any additional stages at room temperature. PMID:22755673

Beev, Nikolai; Kiviranta, Mikko

2012-06-01

100

Thermal stability analysis of AlGaAs\\/GaAs heterojunction bipolar transistors with multiple emitter fingers  

Microsoft Academic Search

A numerical electro-thermal model was developed for AlGaAs\\/GaAs heterojunction bipolar transistors (HBT's) to describe the base current, current gain and output power dependence on junction temperature. The model is applied to microwave HBT devices with multi-emitter fingers. The calculated results of the common-emitter, current-voltage characteristics in the linear active region show a “current crush” effect due to inherent nonuniform junction

L. L. Liou; B. Bayraktaroglu

1994-01-01

101

Very high-power-density CW operation of GaAs\\/AlGaAs microwave heterojunction bipolar transistors  

Microsoft Academic Search

Thermal instability of multi-emitter high-power microwave heterojunction bipolar transistors (HBTs) was eliminated using a novel heat spreading technique that regulates internal device currents to avoid the formation of hot spots. Devices with 2- and 3-?m minimum emitter sizes and no intentional ballast resistors showed unconditionally stable CW operation up to the device electronic limitations. A record 10-mW\\/?m2 power density was

Burhan Bayraktaroglu; J. Barrette; L. Kehias; Chern I. Huang; R. Fitch; R. Neidhard; R. Scherer

1993-01-01

102

High-Current-Gain Direct-Growth GaN\\/InGaN Double Heterojunction Bipolar Transistors  

Microsoft Academic Search

We report high-current-gain n-p-n GaN\\/InGaN double-heterojunction bipolar transistors (DHBTs) using a direct-growth fabrication processing approach. The impact of the indium composition in the base layer was studied, and a burn-in effect using a constant-base-current stressing method was observed. We found that DHBTs with higher indium composition in the InGaN base layer may help reduce the base resistance and lower the

Yi-Che Lee; Yun Zhang; Hee-Jin Kim; Suk Choi; Zachary Lochner; Russell D. Dupuis; Jae-Hyun Ryou; Shyh-Chiang Shen

2010-01-01

103

ESD (Electrostatic Discharge)/EOS (Electrical OverStress) susceptibility of a class of bipolar RF power transistors: Experimental studies on stripline-opposed emitter transistors  

NASA Astrophysics Data System (ADS)

Susceptibility of a class of bipolar RF power transistors (stripline-opposed emitter (SOE) devices) to electrical overstressing (EOS) is studied. Having unique packaging compatible for RF/stripline applications, SOE devices pose prominent/extended exteriors for static propensity and hence are critically vulnerable to degradation as predictable by the charge-device modeling. As such, contrary to the popular notion that rugged bipolar devices are not excessively prone to ESD-based detrimental effects, SOE transistors, on the other hand, are severely vulnerable. It is not just the Wunsch Bell limit of catastrophy due to PN junction burnout (under high-level zaps) that dictates the damages in the devices like SOE transistors. The entire device configuration, i.e., active junction, metallization, bonding, etc., as well as the external packaging, decide the device lethality. This is demonstrated by experimental studies on a family of SOE devices by subjecting them to ESD zaps using a Human Body Simulator. The results positively indicate that their vulnerability is in excess of Class II limit and require specific handling precautions, lest they pose quality control and/or field failure problems. Especially, considering these devices being extremely costly, specific ESD control efforts are rather imminent.

Neelakantaswamy, Perambur S.; Turkman, Ibrahim R.

1986-12-01

104

High-performance AlGaInP tunneling heterostructure-emitter bipolar transistor  

NASA Astrophysics Data System (ADS)

In this paper, a high-performance heterostructure-emitter bipolar transistor employing an AlGaInP quaternary compound tunneling layer is fabricated and demonstrated. In the studied device, a 50 Å n-AlGaInP tunneling emitter layer together with a 200 Å n-GaAs layer forms the heterostructure emitter to decrease the collector-emitter offset voltage. On the other hand, due to the relatively large valence band discontinuity (?0.4 eV) at AlGaInP/GaAs heterojunction and the small hole transmission coefficient across the AlGaInP tunneling layer, most of holes injecting from base to emitter will be blocked at AlGaInP/GaAs heterojunction and then high collector current and current gain are achieved. The experimental results exhibit a large collector current of 92 mA, a large current gain of 446, and a relatively low offset voltage of only 45 mV, respectively. Furthermore, a large current-gain cutoff frequency ft up to 63.7 GHz is obtained for the device with a thin tunneling layer.

Tsai, Jung-Hui

2014-11-01

105

Working toward high-power GaN/InGaN heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

III-nitride (III-N) heterojunction bipolar transistors (HBTs) are a less-explored electronic device technology due to the myriad research issues in material growth, device design and fabrication associated with these devices. For III-N HBTs, npn-GaN/InGaN heterostructures provide the benefits of mitigating the poor base electrical conductivity of p-type GaN and the problematic magnesium incorporation issues. Consequently, InGaN-base III-N HBTs are promising for next-generation high-power RF III-N systems. This paper will describe the current development status of npn GaN/InGaN HBTs grown either on sapphire or free-standing (FS) GaN substrates using optimized metalorganic chemical vapor deposition (MOCVD) and refined HBT processing techniques. Recombination current paths in GaN/InGaN HBTs are studied and small-signal equivalent circuits are developed. The extracted device model indicates that, with further device fabrication technique development, Johnson's figure of merit (JFOM) of GaN/InGaN HBTs can be as high as 5 THz V.

Shen, Shyh-Chiang; Dupuis, Russell D.; Lochner, Zachery; Lee, Yi-Che; Kao, Tsung-Ting; Zhang, Yun; Kim, Hee-Jin; Ryou, Jae-Hyun

2013-07-01

106

Investigation of VLSI Bipolar Transistors Irradiated with Electrons, Ions and Neutrons for Space Application  

NASA Astrophysics Data System (ADS)

A systematic investigation of radiation effects on a BICMOS technology manufactured by STM has been undertaken. Bipolar transistors were irradiated by neutrons, C, Ar and Kr ions, and recently by electrons. Fast neutrons, as well as other types of particles, produce defects mainly by displacing silicon atoms from their lattice positions to interstitial locations, i.e. generating vacancy-interstitial pairs (the so-called Frenkel pairs). Although imparted doses differ largely, the experimental results indicate that the gain (?) variation is mostly related to the non-ionizing energy-loss (NIEL) deposition for neutrons, ions and electrons. The variation of the inverse of the gain degradation, ?(1/?), is found to be linearly related (as predicted by the Messenger-Spratt equation for neutron irradiations) to the concentrations of the Frenkel pairs generated independently of the kind of incoming particle. For space applications, this linear dependence on the concentration of Frenkel pairs allows to evaluate the total amount of the gain degradation of VLSI components due to the flux of charged particles during the full life of operation of any pay-load. In fact, the total amount of expected Frenkel pairs can be estimated taking into account the isotopic spectra. It has to be point out that in cosmic rays there is relevant flux of electrons and isotopes up to Ni, which are within the range of particles presently investigated.

D'Angelo, P.; Fallica, G.; Galbiati, A.; Mangoni, R.; Modica, R.; Pensotti, S.; Rancoita, P. G.

2006-04-01

107

High total dose gamma radiation assessment of commercially available SiGe heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

Maintenance tasks of the future International Experimental Thermonuclear fusion Reactor (ITER) will require communication links between the remotely operated equipment in the reactor vessel and the control room, some of which need to be radiation tolerant up to MGy dose levels. As a key element of opto-electronic transceivers, we therefore assessed the DC behavior of a commercial-off-the-shelf (COTS) SiGe heterojunction bipolar transistor (HBT) under gamma radiation up to 15 MGy, with dose rates from 160 Gy/h to 27 kGy/h. Our in-situ measurements of the forward DC current gain (hfe) present a limited loss of about 30 % for a base current of 100 ?A, with a dependence on the biasing conditions and a thermally activated recovery. These first ever reported results up to MGy levels allow us to design circuit-hardened driving electronics for both photonic transmitters and receivers, enabling high bandwidth communications applied in a fusion reactor environment.

Van Uffelen, Marco; Geboers, Sam; Leroux, Paul; Berghmans, Francis

2005-09-01

108

Multi-level interconnects for heterojunction bipolar transistor integrated circuit technologies  

SciTech Connect

Heterojunction bipolar transistors (HBTs) are mesa structures which present difficult planarization problems in integrated circuit fabrication. The authors report a multilevel metal interconnect technology using Benzocyclobutene (BCB) to implement high-speed, low-power photoreceivers based on InGaAs/InP HBTs. Processes for patterning and dry etching BCB to achieve smooth via holes with sloped sidewalls are presented. Excellent planarization of 1.9 {micro}m mesa topographies on InGaAs/InP device structures is demonstrated using scanning electron microscopy (SEM). Additionally, SEM cross sections of both the multi-level metal interconnect via holes and the base emitter via holes required in the HBT IC process are presented. All via holes exhibit sloped sidewalls with slopes of 0.4 {micro}m/{micro}m to 2 {micro}m/{micro}m which are needed to realize a robust interconnect process. Specific contact resistances of the interconnects are found to be less than 6 {times} 10{sup {minus}8} {Omega}cm{sup 2}. Integrated circuits utilizing InGaAs/InP HBTs are fabricated to demonstrate the applicability and compatibility of the multi-level interconnect technology with integrated circuit processing.

Patrizi, G.A.; Lovejoy, M.L.; Schneider, R.P. Jr.; Hou, H.Q. [Sandia National Labs., Albuquerque, NM (United States); Enquist, P.M. [Research Triangle Inst., Research Triangle Park, NC (United States)

1995-12-31

109

Cathodoluminescence Microcharacterization of Radiative Recombination Centers in Lifetime-Controlled Insulated Gate Bipolar Transistors  

NASA Astrophysics Data System (ADS)

Cross-sectional cathodoluminescence (CL) measurements were applied to the study of electron-irradiated punch-through insulated gate bipolar transistors (IGBTs) to investigate the relationship between radiative recombination centers and electrical characteristics. IGBTs were additionally annealed at temperatures of 200-400 °C for 1 h. As annealing temperature rose, collector-emitter saturation voltage (VCES) decreased and current fall time (tf) increased. The cross-sectional CL measurements showed sharp luminescent peaks at 1018 meV (W or I1), 1040 meV (X or I3), and 790 meV (C) and a broad band at approximately 0.90-1.05 eV. As annealing temperature rose, the intensity of the W line decreased and that of the X line increased, suggesting that small self-interstitial clusters agglomerate and form stable, large self-interstitial clusters reducing the total number of self-interstitial clusters. The C line, which originated from an interstitial oxygen and carbon complex, showed no significant change. We consider that self-interstitial clusters play important roles in the electrical characteristics of lifetime-controlled IGBTs.

Sugie, Ryuichi; Mitani, Takeshi; Yoshikawa, Masanobu; Iwata, Yoshiharu; Satoh, Ryohei

2010-04-01

110

Systematic investigation of monolithic bipolar transistors irradiated with neutrons, heavy ions and electrons for space applications  

NASA Astrophysics Data System (ADS)

In this paper, experimental results of radiation effects on a BiCMOS high speed commercial technology, manufactured by ST-Microelectronics, are reported after irradiation with 9.1 MeV electrons. The data are compared with those previously obtained by irradiations with fast-neutrons, 12C-, 13C-, Ar- and Kr-ions. Fast-neutrons, as well as other types of particles, produce defects, mainly by displacing silicon atoms from their lattice positions to interstitial locations, i.e. generating vacancy-interstitial pairs, the so-called Frenkel pairs, which results in creating recombination centers. As a consequence, the lifetime of the minority-carriers in the base is decreased and the common-emitter current gain ( ?) is degraded. The gain degradation was investigated for collector current Ic between 1 ?A and 1 mA. The linear dependence of ?(1/ ?) = 1/ ?irr - 1/ ? (where ?irr and ? are the gain after and before the irradiation) as a function of the concentration of Frenkel pairs was confirmed. The bipolar transistors made on this technology have shown to be particularly radiation resistant. Base and collector currents were systematically investigated, as well as, the effect of self-annealing.

Consolandi, C.; D'Angelo, P.; Fallica, G.; Mangoni, R.; Modica, R.; Pensotti, S.; Rancoita, P. G.

2006-11-01

111

Highly sensitive, photon number resolving detectors mediated by phonons using $?$-doped GaAs transistors  

E-print Network

We report a photon number resolving detector using two-dimensional electron gas (2DEG) based transistors. When the photon pulses impinge on the absorption region, the generated phonons dissipate ballistically in the 2DEG toward the trench isolated nanowire transistors near the surface. The phonon-electron interaction induces a positive conductance in the transistors, resulting in a current increase. With this principle, we obtain an internal quantum efficiency for this type of detector of up to 85%.

Xiulai Xu; Hugh Baker; David A. Williams

2010-05-03

112

Impact ionization in the base of a hot-electron AlSb/InAs bipolar transistor  

NASA Technical Reports Server (NTRS)

The operation of a new AlSb/InAs heterojunction bipolar transistor is studied. The electrons are injected into a p-InAs base across the AlSb/InAs heterojunction. The conduction-band discontinuity at this heterojunction is sufficiently large so that energy of the electrons injected into InAs exceeds the threshold for generating electron-hole pairs by impact ionization. The observed incremental common base current at zero collector-base bias decreases and becomes negative as the emitter current is increased, thus providing direct evidence for impact ionization entirely by band-edge discontinuities.

Vengurlekar, Arvind S.; Capasso, Federico; Chiu, T. Heng

1990-01-01

113

Electron Transport Behavior on Gate Length Scaling in Sub-50 nm GaAs Metal Semiconductor Field Effect Transistors  

SciTech Connect

Short channel GaAs Metal Semiconductor Field Effect Transistors (MESFETs) have been fabricated with gate length to 20 nm, in order to examine the characteristics of sub-50 nm MESFET scaling. Here the rise in the measured transconductance is mainly attributed to electron velocity overshoot. For gate lengths below 40 nm, however, the transconductance drops suddenly. The behavior of velocity overshoot and its degradation is investigated and simulated by using a transport model based on the retarded Langevin equation (RLE). This indicates the existence of a minimum acceleration length needed for the carriers to reach the overshoot velocity. The argument shows that the source resistance must be included as an internal element, or appropriate boundary condition, of relative importance in any model where the gate length is comparable to the inelastic mean free path of the carriers.

Han, Jaeheon [Department of Electronic Engineering, Kangnam University, 111 Gugal-dong, Giheung-gu, Yongin-city, Gyeonggi-do, Korea 446-702 (Korea, Republic of)

2011-12-23

114

Modeling and Simulation of - and Silicon Germanium-Base Bipolar Transistors Operating at a Wide Range of Temperatures.  

NASA Astrophysics Data System (ADS)

Higher speed at lower cost and at low power consumption is a driving force for today's semiconductor technology. Despite a substantial effort toward achieving this goal via alternative technologies such as III-V compounds, silicon technology still dominates mainstream electronics. Progress in silicon technology will continue for some time with continual scaling of device geometry. However, there are foreseeable limits on achievable device performance, reliability and scaling for room temperature technologies. Thus, reduced temperature operation is commonly viewed as a means for continuing the progress towards higher performance. Although silicon CMOS will be the first candidate for low temperature applications, bipolar devices will be used in a hybrid fashion, as line drivers or in limited critical path elements. Silicon -germanium-base bipolar transistors look especially attractive for low-temperature bipolar applications. At low temperatures, various new physical phenomena become important in determining device behavior. Carrier freeze-out effects which are negligible at room temperature, become of crucial importance for analyzing the low temperature device characteristics. The conventional Pearson-Bardeen model of activation energy, used for calculation of carrier freeze-out, is based on an incomplete picture of the physics that takes place and hence, leads to inaccurate results at low temperatures. Plasma -induced bandgap narrowing becomes more pronounced in device characteristics at low temperatures. Even with modern numerical simulators, this effect is not well modeled or simulated. In this dissertation, improved models for such physical phenomena are presented. For accurate simulation of carrier freeze-out, the Pearson-Bardeen model has been extended to include the temperature dependence of the activation energy. The extraction of the model is based on the rigorous, first-principle theoretical calculations available in the literature. The new model is shown to provide consistently accurate values for base sheet resistance for both Si- and SiGe-base transistors over a wide range of temperatures. A model for plasma-induced bandgap narrowing suitable for implementation in a numerical simulator has been developed. The appropriate method of incorporating this model in a drift -diffusion solver is described. The importance of including this model for low temperature simulation is demonstrated. With these models in place, the enhanced simulator has been used for evaluating and designing the Si- and SiGe-base bipolar transistors. Silicon-germanium heterojunction bipolar transistors offer significant performance and cost advantages over conventional technologies in the production of integrated circuits for communications, computer and transportation applications. Their high frequency performance at low cost, will find widespread use in the currently exploding wireless communication market. However, the high performance SiGe-base transistors are prone to have a low common-emitter breakdown voltage. In this dissertation, a modification in the collector design is proposed for improving the breakdown voltage without sacrificing the high frequency performance. A comprehensive simulation study of p-n-p SiGe-base transistors has been performed. Different figures of merit such as drive current, current gain, cut -off frequency and Early voltage were compared between a graded germanium profile and an abrupt germanium profile. The differences in the performance level between the two profiles diminishes as the base width is scaled down.

Shaheed, M. Reaz

1995-01-01

115

High-speed analog-to-digital conversion with GaAs technology: prospects, trends and obstacles  

Microsoft Academic Search

The authors addresses the prospects for widespread use of GaAs technology for analog-to-digital (A\\/D) conversion, the technological and design trends for improved A\\/D realizations, and the obstacles to the realization of higher speed and resolution. It is noted that GaAs MESFET and HBT (heterojunction bipolar transistor) technology promise an increase in sample rate and achievable resolution for A\\/D conversion compared

L. E. Larson

1988-01-01

116

GaAs/Al/sub 0.3/Ga/sub 0.7/As, heterojunction bipolar transistors for high-temperature (T greater than 300 C), power electronic applications  

NASA Astrophysics Data System (ADS)

Solid-state devices formed from compound semiconductor materials like GaAs, GaP, SiC, and (Al,Ga)As have long been viewed as candidates for use in electronic circuits functioning at temperatures greater than 300C. To address the specific needs of power semiconductor devices operating simultaneously at high currents, voltages, and high temperatures, heterojunction devices formed from combinations of GaAs and (Al,Ga)As have recently been proposed. These novel heterojunction structures display reduced resistive and voltage parasitics when compared to wide-bandgap GaP or SiC, homojunction diodes without seriously compromising control of thermally generated leakage currents. In this study, a prototype, low-power, (Al,Ga)As/GaAs, heterojunction bipolar transistor (HBT) is described which has demonstrated excellent electrical characteristics in the 300 to 400C temperature range. At 350C, the HBT has a common-emitter current gain of 14 (V sub CE = 5V, I sub C = 10 mA) and collector-base leakage of 6.4 x 10 to the -2 power A/cm (V sub CB 5 V).

Zipperian, T. E.; Brennan, T. M.; Hammons, B. E.

117

Indium Phosphide Heterojunction Bipolar Transistors with Emitter Regrowth by Molecular Beam Epitaxy  

NASA Astrophysics Data System (ADS)

A novel InP-based heterojunction bipolar transistor (HBT) technology using molecular beam epitaxy (MBE) regrowth to form the emitter-base heterojunction and emitter capping layers is presented in this dissertation. The motivation for this work is to combining the positive attributes of the SiGe HBT device structure and fabrication technology with the superior attributes of III-V material systems. The intention of this work is to provide initial investigations into the required material properties as well as initial demonstrations of devices with regrown emitters. Low-resistance polycrystalline InAs (poly-InAs) deposited onto silicon nitride (SiNx) dielectric is demonstrated, and an investigation into material property dependencies on deposition conditions is presented. Low-resistance poly-InAs may be used as an emitter capping material in an InP HBT with regrown emitter where the emitter contact material is wider than the base-emitter junction area. An emitter contact area larger than the emitter junction allows scaling of the device to reduce parasitic capacitances without introducing detrimental parasitics to the emitter contact resistance. Such an HBT could be produced using a patterned base-collector template covered in SiNx with openings in the dielectric in areas where emitter junctions are desired. Areas where the base semiconductor is exposed to emitter regrowth would produce a monocrystalline emitter, and areas where deposition occurs onto SiNx would produce polycrystalline material. A graded InAlAs emitter with InAs emitter cap was used in the initial demonstrations of the regrown emitter HBT. Large-area devices were used to successfully demonstrate proof-of-concept devices and to make the first-order improvements required for a small-area RF device demonstration. The first small-area regrown emitter InP HBT with emitter contact area wider than the 0.7 x 8 mum2 base-emitter junction demonstrated 160 GHz peak ft and simultaneous 140 GHz fmax. Further studies into the base-collector template surface preparation process produced an improved regrowth surface with near-epitaxial smoothness. A simplified, abrupt InP emitter regrowth onto this surface produces regrowth similar to what is observed for growth onto epi-ready InP substrates. The improved regrown emitter HBT with 0.7 x 8 mum2 InP emitter area is used to demonstrate a simultaneous 183 GHz ft and 165 GHz fmax.

Scott, Dennis W.

118

4H-SiC Power Bipolar Junction Transistor with a Very Low Specific On- resistance of 2.9 mOmega.cm2.  

National Technical Information Service (NTIS)

This paper reports a newly achieved best result on the specific on- resistance (Rsp,on) of power 4H-SiC bipolar junction transistors (BJT). A 4H- SiC BJT based on a 12 um drift-layer shows a record low specific-on resistance of only 2.9 mOMEGA.sq cm, with...

J. Zhang, J. H. Zhao, P. Alexandrov, T. Burke

2006-01-01

119

Passivation of InP heterojunction bipolar transistors by strain controlled plasma assisted electron beam evaporated hafnium oxide  

NASA Astrophysics Data System (ADS)

We present structural, stress, and electrical properties of plasma assisted e-beam evaporated hafnium dioxide (HfO2) layers on n-type InP substrates. These layers have subsequently been used for surface passivation of InGaAs/InP heterostructure bipolar transistors either alone or in combination with plasma enhanced chemical vapor deposited SiO2 layers. The use of stacked HfO2/SiO2 results in better interface quality with InGaAs/InP heterostructures, as illustrated by smaller leakage current and improved breakdown voltage. These improvements can be attributed to the reduced defect density and charge trapping at the dielectric-semiconductor interface. The deposition at room temperature makes these films suitable for sensitive devices.

Driad, R.; Sah, R. E.; Schmidt, R.; Kirste, L.

2012-01-01

120

Electrical stress-induced instability of amorphous indium-gallium-zinc oxide thin-film transistors under bipolar ac stress  

SciTech Connect

Bipolar ac stress-induced instability of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors is comparatively investigated with that under a positive dc gate bias stress. While the positive dc gate bias stress-induced threshold voltage shift ({delta}V{sub T}) is caused by the charge trapping into the interface/gate dielectric as reported in previous works, the dominant mechanism of the ac stress-induced {delta}V{sub T} is observed to be due to the increase in the acceptorlike deep states of the density of states (DOS) in the a-IGZO active layer. Furthermore, it is found that the variation of deep states in the DOS makes a parallel shift in the I{sub DS}-V{sub GS} curve with an insignificant change in the subthreshold slope, as well as the deformation of the C{sub G}-V{sub G} curves.

Lee, Sangwon; Jeon, Kichan; Park, Jun-Hyun; Kim, Sungchul; Kong, Dongsik; Kim, Dong Myong; Kim, Dae Hwan [School of Electrical Engineering, Kookmin University, 861-1 Jeongneung-dong, Seongbuk-gu, Seoul 136-702 (Korea, Republic of); Kim, Sangwook; Kim, Sunil; Hur, Jihyun; Park, Jae Chul; Song, Ihun; Kim, Chang Jung; Park, Youngsoo; Jung, U-In [Semiconductor Laboratory, Samsung Advanced Institute of Technology, Nongseo-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do 446-712 (Korea, Republic of)

2009-09-28

121

Development of a radiation hardened npn bipolar transistor for a 64K CMOS fusible-link PROM  

SciTech Connect

A 1.2 [mu]m CMOS production process was adapted to produce a 64K CMOS fusible-link Programmable Read-Only Memory (PROM) for space applications. The circuit requirement of less than 50 nS access time combined with the need for 9 volt single pulse programming of the fusible links and radiation tolerance to levels over 300 Krad(Si) made close collaboration between design engineering, reliability engineering, and device engineering essential for a successful project. A vertical NPN bipolar transistor was integrated into a standard CMOS process to be used for programming and reading the fuses. The device characteristics were carefully matched to the product speed and programmability requirements. The NPN device was optimized for radiation performances. Successful development required extensive use of process and device modeling, test structure design and measurement, and experimental design methods.

Fuller, R.; Newman, W. (Harris Semiconductor, Melbourne, FL (United States))

1994-12-01

122

New isolated gate bipolar transistor two-quadrant chopper power supply for a fast field cycling nuclear magnetic resonance spectrometer  

NASA Astrophysics Data System (ADS)

This work, presents, for the first time, an Isolated Gate Bipolar Transistor (IGBT) two-quadrant chopper power supply for a fast field cycling (FFC) nuclear magnetic resonance spectrometer. This power supply was designed to achieve a maximum current of 200 A with good efficiency, low semiconductor losses, low cost, and easy maintenance. Both energy storage circuits and dumping circuits are used to obtain switching times less than 2 ms between field levels in agreement with the FFC technique specifications. The current ripple at high currents is better than 1×10-4 and presents a specific shape which can be used for additional compensation using auxiliary circuits. The implemented power supply was tested and been continuously operating with a home-built FFC solenoidal magnet, associated cooling system, and rf units for fields between 0 and 0.2 T.

Sousa, D. M.; Marques, G. D.; Sebastião, P. J.; Ribeiro, A. C.

2003-10-01

123

A new InGaP/GaAs tunneling heterostructure-emitter bipolar transistor (T-HEBT)  

SciTech Connect

Excellent characteristics of an InGaP/GaAs tunneling heterostructure-emitter bipolar transistor (T-HEBT) are first demonstrated. The insertion of a thin n-GaAs emitter layer between tynneling confinement and base layers effectivelty eliminates the potential spike at base-emitter junction and reduces the collector-emitter offset voltage, while the thin InGaP tunneling confinement layer is employed to reduce the transporting time across emitter region for electrons and maintain the good confinement effect for holes. Experimentally, the studied T-HEBN exhibits a maximum current gain of 285, a relatively low offset voltage of 40 mW, and a current-gain cutoff frequency of 26.4 GHz.

Tsai, Jung-Hui, E-mail: jhtsai@nknucc.nknu.edu.tw [National Kaohsiung Normal University, Department of Electronic Engineering, Taiwan (China); Lee, Ching-Sung [Feng Chia University, Department of Electronic Engineering, Taiwan (China); Lour, Wen-Shiung [National Taiwan Ocean University, Department of Electrical Engineering, Taiwan (China); Ma, Yung-Chun; Ye, Sheng-Shiun [National Kaohsiung Normal University, Department of Electronic Engineering, Taiwan (China)

2011-05-15

124

Simulation of Npn and Pnp AlGaN/GaN heterojunction bipolar transistors performances: Limiting factors and optimum design  

SciTech Connect

The performance capabilities of Npn and Pnp AlGaN/GaN heterojunction bipolar transistors have been investigated by using a drift-diffusion transport model. Numerical results have been employed to study the effect of the p-type Mg doping and its incomplete ionization on device performance. The high base resistance induced by the deep acceptor level is found to be the cause of limited current gain values for Npn devices. Several computation approaches have been considered to improve their performance. Reasonable improvement of the DC current gain {beta} is observed by realistically reducing the base thickness in accordance with processing limitations. Base transport enhancement is also predicted by the introduction of a quasi-electric field in the base. The impact of the base resistivity on high-frequency characteristics is investigated for Npn AlGaN/GaN devices. Optimized predictions with maximum oscillation frequency value as high as f{sub MAX} = 20 GHz and a unilateral power gain--U = 25 dB make this bipolar GaN-based technology compatible with communication applications. Simulation results reveal that the restricted amount of free carriers from the p-doped emitter limits Pnp's DC performances operating in common emitter configuration. A preliminary analysis of r.f. characteristics for the Pnp counterpart indicates limited performance mainly caused by the degraded hole mobility.

MONIER,C.; REN,F.; HAN,JUNG; CHANG,PING-CHIH; SHUL,RANDY J.; LEE,K.P.; ZHANG,A.P.; BACA,ALBERT G.; PEARTON,S.J.

2000-04-25

125

Ballistic versus diffusive base transport in the high-frequency characteristics of bipolar transistors  

E-print Network

Ballistic versus diffusive base transport in the high-frequency characteristics of bipolar a universal character both in the diffusion limit ( W)Z,,) and the ballistic limit (I,,. IV). In the latter ("ballistic") limit Z& W, the second term in Eqs. (4) and (5) is negligible 2770 Appl. Phys. Lett. 60 (22), 1

Luryi, Serge

126

e bipolar junction transistor (BJT) is historically the first solid-state analog amplifier and digital switch, and formed the basis of integrated circuits (IC) in the 1970s. Starting in the early 1980s, the  

E-print Network

, the invention of silicon­germanium base heterojunction bipolar transistor (SiGe HBT) brought the bipolar line communications applications. Today, SiGe HBTs are used to design radio-frequency integrated radar, wireless distribution of cable television, millimeter wave radios, and many more applications

Wilamowski, Bogdan Maciej

127

Characterization and measurement of the base and emitter resistances of bipolar transistors  

Microsoft Academic Search

Most previously published methods of measuring transistor base resistance are surveyed and compared. The input impedance circle diagram method is examined in detail and correction factors due to parasitic capacitances are derived. Emitter series resistance is also estimated from this data. A new method of measuring base resistance requiring much less measurement effort is introduced and shown to give good

WILLY M. C. SANSEN; R. G. Meyer

1972-01-01

128

Random telegraph signal noise mechanisms in reverse base current of hot carrier-degraded submicron bipolar transistors: Effect of carrier trapping during stress on noise characteristics  

Microsoft Academic Search

We investigate physical mechanisms of random telegraph signal (RTS) noise in reverse base current of hot carrier-degraded polysilicon emitter bipolar junction transistors. RTS noise, analyzed in the time domain, is studied as a function of reverse base-emitter bias, temperature, and additional reverse-bias stress. Two-level RTS with a relative amplitude as high as 100% is observed at room temperature. The RTS

D. Pogany; J. A. Chroboczek; G. Ghibaudo

2001-01-01

129

High current gain graded GaN\\/InGaN heterojunction bipolar transistors grown on sapphire and SiC substrates by metalorganic chemical vapor deposition  

Microsoft Academic Search

High-current-gain GaN\\/InGaN double heterojunction bipolar transistors having a graded-base and emitter design grown on sapphire and SiC substrates by metalorganic chemical vapor deposition are presented. Improved device performances result from the improvement of the InGaN graded layer material quality and the p-type doping enhancement as well as the improvement of device fabrication techniques. The devices show common-emitter incremental current gain

T. Chung; D. M. Keogh; J.-H. Ryou; D. Yoo; J. Limb; W. Lee; S.-C. Shen; P. M. Asbeck; R. D. Dupuis

2007-01-01

130

Silicon-germanium base heterojunction bipolar transistors by molecular beam epitaxy  

Microsoft Academic Search

The devices were fabricated using molecular-beam epitaxy (MBE), low-temperature processing, and germanium concentrations of 0, 6%, and 12%. The transistors demonstrate current gain, and show the expected increase in collector current as a result of reduced bandgap due to Ge incorporation in the base. For a 1000-Å base device containing 12% Ge, a six-times increase in collector current was measured

GARY L. PATTON; SUBRAMANIAN S. IYER; SYLVAIN L. DELAGE; S. Tiwari; J. M. C. Stork

1988-01-01

131

A 65-kV insulated gate bipolar transistor switch applied in damped AC voltages partial discharge detection system  

NASA Astrophysics Data System (ADS)

Damped AC voltages detection system (DAC) is a productive way to detect the faults in power cables. To solve the problems of large volume, complicated structure and electromagnetic interference in existing switches, this paper developed a compact solid state switch based on electromagnetic trigger, which is suitable for DAC test system. Synchronous electromagnetic trigger of 32 Insulated Gate Bipolar Transistors (IGBTs) in series was realized by the topological structure of single line based on pulse width modulation control technology. In this way, external extension was easily achieved. Electromagnetic trigger and resistor-capacitor-diode snubber circuit were optimized to reduce the switch turn-on time and circular layout. Epoxy encapsulating was chosen to enhance the level of partial discharge initial voltage (PDIV). The combination of synchronous trigger and power supply is proposed to reduce the switch volume. Moreover, we have overcome the drawback of the electromagnetic interference and improved the detection sensitivity of DAC by using capacitor storage energy to maintain IGBT gate driving voltage. The experimental results demonstrated that the solid-state switch, with compact size, whose turn-on time was less than 400 ns and PDIV was more than 65 kV, was able to meet the actual demands of 35 kV DAC test system.

Jiang, J.; Ma, G. M.; Luo, D. P.; Li, C. R.; Li, Q. M.; Wang, W.

2014-02-01

132

Optimization of direct current performance in terahertz InGaAs/InP double-heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

As the dimensions of In0.53Ga0.47As/InP double-heterojunction bipolar transistors (DHBTs) scale for terahertz applications, the DC current (?) decreases. To improve the DC performance in such scaled devices, we analyze three modified HBT geometries: a HBT with a surface pulse-doped layer in the base, a HBT having this pulse-doped layer under the emitter junction and under the base contact, but with it removed by etching in the region between the base and emitter contacts, and a device, necessarily fabricated by regrowth, in which the pulsed doped layer is present under only the base contacts. Based on a drift-diffusion/recombination model, carrier transport in the DHBT base is simulated and the corresponding ? is computed using TCAD software. The structures with a pulse doped layer can attain ? = 31 ˜ 39 at 100 nm emitter width. The structures with a trench between the base contact and emitter show ? = 39 ˜ 54 at 100 nm emitter width. Finally, the structure with recessed base-emitter junction and regrown emitter demonstrate ? = 62-119 at 100 nm emitter width.

Chiang, Han-Wei; Rode, Johann C.; Choudhary, Prateek; Rodwell, Mark J. W.

2014-10-01

133

Variable-angle spectroscopic ellipsometry of InAlP native oxide dielectric layers for GaAs metal-oxide-semiconductor field effect transistor applications  

NASA Astrophysics Data System (ADS)

Variable angle spectroscopic ellipsometry models and data analysis have been developed to accurately determine the thickness of indium aluminum phosphide (InAlP) native oxide films used for the gate oxide in GaAs-based metal-oxide-semiconductor field effect transistor devices. The optical constants of the InAlP oxide, as well as InAlP and indium aluminum phosphide (InGaP) lattice matched to GaAs, have been determined by ellipsometry measurements using a photon energy range of 1.45 to 5.45 eV. Using the optical constants of InAlP and InAlP oxide, an ellipsometry-based model has been developed to characterize the oxidation kinetics of a thick partially oxidized InAlP epitaxial film grown on GaAs. The data indicate a delay in the full oxidation of In relative to Al as InAlP is fully oxidized. Excellent agreement between the thickness values determined by transmission electron microscopy imaging and by ellipsometric modeling validates the optical constants obtained. The ellipsometry material parameter models have also been extended to accurately fit the thickness of <100 Å InAlP oxides grown directly upon a multi-layer heterostructure for use as a transistor gate oxide. The InAlP oxide thicknesses determined by ellipsometry agree with those determined by electron microscopy to within 4%.

Yuan, Wangqing; Hall, D. C.

2013-03-01

134

Heavy-ion broad-beam and microprobe studies of single-event upsets in 0.20 um SiGe heterojunction bipolar transistors and circuits.  

SciTech Connect

Combining broad-beam circuit level single-event upset (SEU) response with heavy ion microprobe charge collection measurements on single silicon-germanium heterojunction bipolar transistors improves understanding of the charge collection mechanisms responsible for SEU response of digital SiGe HBT technology. This new understanding of the SEU mechanisms shows that the right rectangular parallele-piped model for the sensitive volume is not applicable to this technology. A new first-order physical model is proposed and calibrated with moderate success.

Fritz, Karl (Mayo Foundation, Rochester, MN); Irwin, Timothy J. (Jackson & Tull Chartered Engineers, Washington, DC); Niu, Guofu (Auburn University, Auburn, AL); Fodness, Bryan (SGT, Inc., Greenbelt, MD); Carts, Martin A. (Raytheon ITSS, Greenbelt, MD); Marshall, Paul W. (Brookneal, VA); Reed, Robert A. (NASA/GSFC, Greenbelt, MD); Gilbert, Barry (Mayo Foundation, Rochester, MN); Randall, Barbara (Mayo Foundation, Rochester, MN); Prairie, Jason (Mayo Foundation, Rochester, MN); Riggs, Pam (Mayo Foundation, Rochester, MN); Pickel, James C. (PR& T, Inc., Fallbrook, CA); LaBel, Kenneth (NASA/GSFC, Greenbelt, MD); Cressler, John D. (Georgia Institute of Technology, Atlanta, GA); Krithivasan, Ramkumar (Georgia Institute of Technology, Atlanta, GA); Dodd, Paul Emerson; Vizkelethy, Gyorgy

2003-09-01

135

Extrinsic Base Regrowth of p-InGaN for Npn-Type GaN\\/InGaN Heterojunction Bipolar Transistors  

Microsoft Academic Search

The regrowth of p-InGaN as the extrinsic base layer of Npn-type GaN\\/InGaN heterojunction bipolar transistors (HBTs) significantly improves the ohmic characteristics of the base layer. The specific contact resistance is 7.8× 10-4 Omega\\\\cdotcm2 even after the dry etching. This value for a non-alloyed ohmic contact is much better than that for as-grown p-GaN (1.7× 10-3 Omega\\\\cdotcm2) and decreased turn-on voltage

Toshiki Makimoto; Kazuhide Kumakura; Naoki Kobayashi

2004-01-01

136

NpN-GaN/InxGa1-xN/GaN heterojunction bipolar transistor on free-standing GaN substrate  

NASA Astrophysics Data System (ADS)

Data and analysis are presented for NpN-GaN/InGaN/GaN double-heterojunction bipolar transistors (HBTs) grown and fabricated on a free-standing GaN (FS-GaN) substrate in comparison to that on a sapphire substrate to investigate the effect of dislocations in III-nitride HBT epitaxial structures. The performance characteristics of HBTs on FS-GaN exhibit a maximum collector current density of ˜12.3 kA/cm2, dc current gain of ˜90, and maximum differential gain of ˜120 without surface passivation, representing a substantial improvement over similar devices grown on sapphire. This is attributed to the reduction in threading dislocation density afforded by using a homoepitaxial growth on a high-crystalline-quality substrate. The minority carrier diffusion length increases significantly owing to not only a mitigated carrier trap effect via fewer dislocations, but also possibly reduced microscopic localized states.

Lochner, Zachary; Jin Kim, Hee; Lee, Yi-Che; Zhang, Yun; Choi, Suk; Shen, Shyh-Chiang; Doug Yoder, P.; Ryou, Jae-Hyun; Dupuis, Russell D.

2011-11-01

137

Germanium content and base doping level influence on extrinsic base resistance and dynamic performances of SiGe:C heterojunction bipolar transistors  

NASA Astrophysics Data System (ADS)

We describe a reliable technique to separate the different contributions to the apparent base resistance (RB = RBx + X RBi) of silicon germanium carbon (SiGe:C) heterojunction bipolar transistors (HBTs). The extrinsic base resistance (RBx) is quantified using small-signal measurements. The base-collector junction distribution factor (X) and the intrinsic base resistance (RBi) are extracted from high frequency noise (MWN) measurements. This method is applied to five different SiGe:C HBTs varying in base doping level and germanium content. The results show that high doping levels improve high frequency noise performances while germanium gradient helps to maintain outstanding dynamic performances. This method could be used to elucidate the base technological configuration that ensures low noise together with remarkable dynamic performances in state-of-the-art SiGe:C HBTs.

Ramirez-Garcia, E.; Zerounian, N.; Aniel, F.; Valdez-Monroy, L. A.; Rodriguez-Mendez, L. M.; Valdez-Perez, D.; Galaz-Larios, M. C.; Enciso-Aguilar, M. A.

2014-09-01

138

The 11th International Symposium on Wireless Personal Multimedia Communications (WPMC 2008) Development of THz TransistorsDevelopment of THz Transistors  

E-print Network

) Development of THz TransistorsDevelopment of THz Transistors & (300-3000 GHz) Sub-mm-Wave ICs Mark Rodwell;UCSB High-Frequency Electronics Group THz InP Bipolar TransistorsTHz InP Bipolar Transistors. III V-200 GHz Silicon ICs mm-waves: MIMO links, arrays, sensor networks fiber optics #12;Multi-THz Transistors

Rodwell, Mark J. W.

139

Impurity diffusion behavior of bipolar transistor under low-temperature furnace annealing and high-temperature RTA and its optimization for 0.5-?m Bi-CMOS process  

Microsoft Academic Search

A low-temperature-processed (800-850°C) bipolar transistor design suitable for the high-performance 0.5-?m BiCMOS process is discussed. It has been found that insufficient activation of arsenic in the emitter, enhanced boron diffusion in the low-concentration base region. and insufficient arsenic diffusion from the poly Si are serious considerations if low-temperature furnace annealing is used. If high-temperature rapid thermal annealing (RTA) is used

Masayuki Norishima; Hiroshi Iwai; Youichiro Niitsu; Kenji Maeguchi

1992-01-01

140

ULTRAHIGH-SPEED DIPOLAR TRANSISTORS  

E-print Network

ULTRAHIGH-SPEED DIPOLAR TRANSISTORS Understanding nonequilibrium electron transport in Ill-V compound semiconductors has helped in the development of the fastest bipolar transistors. A. F. J. Levi, R. N. Noltenburg, Y. K. Chen and M. B. Panish The invention of the transistor in the late 1940s has had

Levi, Anthony F. J.

141

Random telegraph signal noise mechanisms in reverse base current of hot carrier-degraded submicron bipolar transistors: Effect of carrier trapping during stress on noise characteristics  

NASA Astrophysics Data System (ADS)

We investigate physical mechanisms of random telegraph signal (RTS) noise in reverse base current of hot carrier-degraded polysilicon emitter bipolar junction transistors. RTS noise, analyzed in the time domain, is studied as a function of reverse base-emitter bias, temperature, and additional reverse-bias stress. Two-level RTS with a relative amplitude as high as 100% is observed at room temperature. The RTS amplitude varies exponentially with the applied reverse base-emitter voltage and depends weakly on temperature. The additional hot carrier stress is observed to induce changes in RTS amplitude and mean pulse widths (independent or correlated), and a disappearance/reappearance of the RTS fluctuations. The results are interpreted by a model where the RTS noise is caused by fluctuations of generation-recombination (g-r) parameters (i.e., capture cross sections and energy position in the gap) of a stress-induced complex bistable defect (CBD) at the Si/SiO2 interface. The complex defect is assumed to be either a two-state fast interface state or an interacting pair of a fast interface state with a slow neighboring border trap. The RTS amplitude is well explained by fluctuations in a single-defect electric-field-enhanced g-r rate between a finite value and naught. The RTS amplitude-bias characteristics and their temperature dependence are satisfactorily accounted for by an expression for a phonon-assisted tunneling current via a single deep-level state. The model parameters are the g-r parameters of the defect and its spatial position in the base-emitter p-n junction. The stress-induced changes in the RTS noise are attributed to the influence of log-time trapping of hot carriers on border states laying in the vicinity of a CBD center. The charged border traps interact with a CBD, changing both its g-r parameters and the RTS switching behavior. The variations in RTS parameters are related to the microscopic nature of the interaction and are discussed for the two types of the CBDs.

Pogany, D.; Chroboczek, J. A.; Ghibaudo, G.

2001-04-01

142

Broad Beam and Ion Microprobe Studies of Single-Event Upsets in High Speed 0.18micron Silicon Germanium Heterojunction Bipolar Transistors and Circuits  

NASA Technical Reports Server (NTRS)

SiGe based technology is widely recognized for its tremendous potential to impact the high speed microelectronic industry, and therefore the space industry, by monolithic incorporation of low power complementary logic with extremely high speed SiGe Heterojunction Bipolar Transistor (HBT) logic. A variety of studies have examined the ionizing dose, displacement damage and single event characteristics, and are reported. Accessibility to SiGe through an increasing number of manufacturers adds to the importance of understanding its intrinsic radiation characteristics, and in particular the single event effect (SEE) characteristics of the high bandwidth HBT based circuits. IBM is now manufacturing in its 3rd generation of their commercial SiGe processes, and access is currently available to the first two generations (known as and 6HP) through the MOSIS shared mask services with anticipated future release of the latest (7HP) process. The 5 HP process is described and is characterized by a emitter spacing of 0.5 micron and a cutoff frequency ff of 50 GHz, whereas the fully scaled 7HP HBT employs a 0.18 micron emitter and has an fT of 120 GHz. Previous investigations have the examined SEE response of 5 HP HBT circuits through both circuit testing and modeling. Charge collection modeling studies in the 5 H P process have also been conducted, but to date no measurements have been reported of charge collection in any SiGe HBT structures. Nor have circuit models for charge collection been developed in any version other than the 5 HP HBT structure. Our investigation reports the first indications of both charge collection and circuit response in IBM s 7HP-based SiGe process. We compare broad beam heavy ion SEU test results in a fully function Pseudo-Random Number (PRN) sequence generator up to frequencies of 12 Gbps versus effective LET, and also report proton test results in the same circuit. In addition, we examine the charge collection characteristics of individual 7HP HBT structures and map out the spatial sensitivities using the Sandia Focused Heavy Ion Microprobe Facility s Ion Beam Induced Charge Collection (IBICC) technique. Combining the two data sets offers insights into the charge collection mechanisms responsible for circuit level response and provides the first insights into the SEE characteristics of this latest version of IBM s commercial SiGe process.

Reed, Robert A.; Marshall, Paul W.; Pickel, Jim; Carts, Martin A.; Irwin, TIm; Niu, Guofu; Cressler, John; Krithivasan, Ramkumar; Fritz, Karl; Riggs, Pam

2003-01-01

143

Advances in Linear Modeling of Microwave Transistors  

Microsoft Academic Search

Heterojunction field effect transistors (HFET) based on gallium nitride (AlGaN\\/GaN) and metal semiconductor field effect transistors (MESFETs) based on silicon carbide (SiC) are the preferred transistors for high-power amplifier circuit designs rather than MESFETs, high electron mobility transistors (HEMTs) and pseudomorphic HEMTs based on gallium arsenide (GaAs) or indium phosphide (InP) semiconductor technology. While AlGaN\\/GaN and SiC are good candidates

Andres Zarate-de Landa; José Eleazar Zúñiga-Juárez; José Raúl Loo-Yau; J. Reynoso-Hernandez; Maria Maya-Sanchez; Juan Luis del Valle-Padilla

2009-01-01

144

Realising high-current gain p-n-p transistors using a novel surface accumulation layer transistor  

E-print Network

Realising high-current gain p-n-p transistors using a novel surface accumulation layer transistor accumulation layer transistor (SALTran) on SOI, which uses the concept of surface accumulation of holes near of the previously published conventional p-n-p lateral bipolar transistor (LBT) structure. From the simulation

Kumar, M. Jagadesh

145

Design of a InP/In1-xGaxAsyP1-y/In0.53Ga0.47As emitter-base junction in a Pnp heterojunction bipolar transistor for increased hole injection efficiency  

NASA Astrophysics Data System (ADS)

Starting with Burt's envelope function theory, we calculate the transmission coefficients of holes across an InP/In1-xGaxAsyP1-y/In0.53Ga0.47As heterointerface while varying the width and gallium and arsenic fractions of the InP lattice-matched quaternary compound (x=0.47y). While comparing our results to the case of an abrupt InP/In0.53Ga0.47As interface, we find that the transmission coefficients of both heavy- and light-holes can be enhanced significantly for a 60-Å-wide quaternary layer with an arsenic fraction y=0.4 (x=0.188). This should lead to an enhanced hole injection efficiency of Pnp heterojunction bipolar transistors using the heterointerface analyzed here as an improved design of the emitter-base junction.

Ekbote, S.; Cahay, M.; Roenker, K.

1999-08-01

146

Effect of graded triple delta-doped sheets on the performance of GaAs based dual channel pseudomorphic high electron mobility transistors  

Microsoft Academic Search

The characteristics of InGaP\\/InGaAs\\/GaAs dual channel pseudomorphic high electron mobility transistors (DCPHEMTs) with different graded triple delta-doped sheets are investigated and experimentally demonstrated. Based on a two-dimensional simulator of ATLAS, the band diagrams, electron densities and DC characteristics of studied devices are comprehensively analyzed. Due to the use of properly graded triple delta-doped sheets, good pinch-off and saturation characteristics, improved

Kuei-Yi Chu; Shiou-Ying Cheng; Meng-Hsueh Chiang; Yi-Jung Liu; Chien-Chang Huang; Tai-You Chen; Chi-Shiang Hsu; Wen-Chau Liu; Wen-Yu Cheng; Bin-Cian Lin

2011-01-01

147

Carbon doping in molecular beam epitaxy of GaAs from a heated graphite filament  

NASA Technical Reports Server (NTRS)

Carbon doping of GaAs grown by molecular beam epitaxy has been obtained for the first time by use of a heated graphite filament. Controlled carbon acceptor concentrations over the range of 10 to the 17th-10 to the 20th/cu cm were achieved by resistively heating a graphite filament with a direct current power supply. Capacitance-voltage, p/n junction and secondary-ion mass spectrometry measurements indicate that there is negligible diffusion of carbon during growth and with postgrowth rapid thermal annealing. Carbon was used for p-type doping in the base of Npn AlGaAs/GaAs heterojunction bipolar transistors. Current gains greater than 100 and near-ideal emitter heterojunctions were obtained in transistors with a carbon base doping of 1 x 10 to the 19th/cu cm. These preliminary results indicate that carbon doping from a solid graphite source may be an attractive substitute for beryllium, which is known to have a relatively high diffusion coefficient in GaAs.

Malik, R. J.; Nottenberg, R. N.; Schubert, E. F.; Walker, J. F.; Ryan, R. W.

1988-01-01

148

Electrical degradation mechanisms of RF power GaAs PHEMTs  

E-print Network

GaAs Pseudomorphic High-Electron Mobility Transistors (PHEMTs) are widely used in RF power applications. Since these devices typically operate at high power levels and under high voltage biasing, their electrical reliability ...

Villanueva, Anita A. (Anita Ariel), 1978-

2007-01-01

149

IEEE BCTM 4.2 Study ofbipolar transistor matching at high current level with various  

E-print Network

IEEE BCTM 4.2 Study ofbipolar transistor matching at high current level with various test-mail: samuel.bordez@st.com, Tel: +33 4 38 92 29 30 Abstract - Matching of bipolar transistors has been. INTRODUCTION Bipolar transistor matching is often described in a medium current zone. Yet, results at high

McNeill, John A.

150

Ultra-stable oscillator with complementary transistors  

NASA Technical Reports Server (NTRS)

A high frequency oscillator, having both good short and long term stability, is formed by including a piezoelectric crystal in the base circuit of a first bi-polar transistor circuit, the bi-polar transistor itself operated below its transitional frequency and having its emitter load chosen so that the input impedance, looking into the base thereof, exhibits a negative resistance in parallel with a capacitive reactance. Combined with this basic circuit is an auxiliary, complementary, second bi-polar transistor circuit of the same form with the piezoelectric crystal being common to both circuits. By this configuration small changes in quiescent current are substantially cancelled by opposite variations in the second bi-polar transistor circuit, thereby achieving from the oscillator a signal having its frequency of oscillation stable over long time periods as well as short time periods.

Kleinberg, L. L. (inventor)

1974-01-01

151

Molecular beam epitaxial growth of metamorphic AlInSb/GaInSb high-electron-mobility-transistor structures on GaAs substrates for low power and high frequency applications  

SciTech Connect

We report on molecular beam epitaxial growth of AlInSb/GaInSb metamorphic high-electron-mobility-transistor structures for low power, high frequency applications on 4 in. GaAs substrates. The structures consist of a Ga{sub 0.4}In{sub 0.6}Sb channel embedded in Al{sub 0.4}In{sub 0.6}Sb barrier layers which are grown on top of an insulating metamorphic buffer, which is based on the linear exchange of Ga versus In and a subsequent exchange of As versus Sb. Precise control of group V fluxes and substrate temperature in the Al{sub 0.4}In{sub 0.6}As{sub 1-x}Sb{sub x} buffer is essential to achieve high quality device structures. Good morphological properties were achieved demonstrated by the appearance of crosshatching and root mean square roughness values of 2.0 nm. Buffer isolation is found to be >100 k{Omega}/{open_square} for optimized growth conditions. Hall measurements at room temperature reveal electron densities of 2.8x10{sup 12} cm{sup -2} in the channel at mobility values of 21.000 cm{sup 2}/V s for single-sided Te volume doping and 5.4x10{sup 12} cm{sup -2} and 17.000 cm{sup 2}/V s for double-sided Te {delta}-doping, respectively.

Loesch, R.; Aidam, R.; Kirste, L.; Leuther, A. [Fraunhofer Institute for Applied Solid-State Physics (IAF), Tullastrasse 72, 79108 Freiburg (Germany)

2011-02-01

152

52 GHz epitaxial base bipolar transistor with high Early voltage of 26.5 V with box-like base and retrograded collector impurity profiles  

Microsoft Academic Search

UHV-CVD epitaxial base transistors having 52 GHz cutoff frequency and 26.5 V Early voltage have been fabricated by adopting a box like base and retrograded collector impurity profiles. In addition, to improve the epitaxial film quality, a hydrotermination technique is used

K. Inou; S. Matsuda; H. Nakajima; N. Sugiyama; K. Usuda; S. Imai; Y. Kawaguchi; K. Yamada; Y. Katsumata; H. Iwai

1994-01-01

153

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 50, NO. 3, MARCH 2003 645 Transistor Design and Application Considerations for  

E-print Network

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 50, NO. 3, MARCH 2003 645 Transistor Design, and Seshadri Subbanna, Member, IEEE Invited Paper Abstract--SiGe HBT transistors achieving over 200 GHz and MAX--BiCMOS integrated circuits, bipolar transistors, heterojunctions, semiconductor devices. I. INTRODUCTION BIPOLAR

Rieh, Jae-Sung

154

GaAs optoelectronic neuron arrays  

NASA Technical Reports Server (NTRS)

A simple optoelectronic circuit integrated monolithically in GaAs to implement sigmoidal neuron responses is presented. The circuit integrates a light-emitting diode with one or two transistors and one or two photodetectors. The design considerations for building arrays with densities of up to 10,000/sq cm are discussed.

Lin, Steven; Grot, Annette; Luo, Jiafu; Psaltis, Demetri

1993-01-01

155

Bipolar disorder  

MedlinePLUS

Bipolar disorder is a condition in which a person has periods of depression and periods of being extremely ... Bipolar disorder affects men and women equally. It usually starts between ages 15 and 25. The exact cause ...

156

Bipolar disorder.  

PubMed

Essential facts Bipolar disorder is a potentially lifelong and disabling condition. Bipolar I, characterised by episodes of mania and depression, is estimated to affect 1 per cent of the adult population. Bipolar II, characterised by hypomania and depression, affects an estimated 0.4 per cent of adults. Episodes can vary in length and frequency. PMID:25351068

2014-10-29

157

Simulating Single-Event Upsets in Bipolar RAM's  

NASA Technical Reports Server (NTRS)

Simulation technique saves testing. Uses interactive version of SPICE (Simulation Program with Integrated Circuit Emphasis). Device and subcircuit models available in software used to construct macromodel for an integrated bipolar transistor. Time-dependent current generators placed inside transistor macromodel to simulate charge collection from ion track. Significant finding of experiments is standard design practice of reducing power in unaddressed bipolar RAM cell increases sensitivity of cell to single-event upsets.

Zoutendyk, J. A.

1986-01-01

158

THz Transistors: Design and Process Technologies Mark J.W. Rodwella  

E-print Network

THz Transistors: Design and Process Technologies Mark J.W. Rodwella , Vibhor Jaina , Evan Lobissera and Materials, University of California, San Diego Abstract: To obtain THz bandwidths in either bipolar or field and 1-3 THz cutoff frequencies... Keywords: Heterojunction bipolar transistors, MOSFETs, THz electronics

Rodwell, Mark J. W.

159

Advances in bipolar IC technology  

NASA Astrophysics Data System (ADS)

Si bipolar transistors and integrated circuits are widely used for high performance gate arrays and high speed cache memories, and have since become the backbone of the high speed computers. Steady improvements in the understanding of the design and scaling of the small dimension bipolar transistors together with the advances in the process technology have led to the realization of ever faster bipolar transistor and circuits. The improvement is expected from scaling down to 0.25 micron dimension. The theoretical limit of scaling is reached when the base width is reduced to about 25 nm. At such a dimension, the mean free path of electron is comparable to the base width and the validity of the statistical drift diffusion equation describing the device operation becomes questionable. Various second order effects in device physics which were of no concern in designing 2 micron or larger devices now become important at one micron and submicron level. They are the heavy doping effects in the base, the reverse tunneling current, the contact to the shallow emitter and the base widening effects. These and further advances are briefly discussed.

Tang, D. D.; Ning, T. H.

1987-10-01

160

Bipolar Disorder.  

ERIC Educational Resources Information Center

Bipolar disorder, a brain disorder that causes unusual shifts in a person's mood, affects approximately one percent of the population. It commonly occurs in late adolescence and is often unrecognized. The diagnosis of bipolar disorder is made on the basis of symptoms, course of illness, and when possible, family history. Thoughts of suicide are…

Spearing, Melissa

161

Impact of strained GaAs spacer between InP emitter and GaAs1-ySby base on structural properties and electrical characteristics of MOCVD-grown InP/GaAs1-ySby/InP DHBTs  

NASA Astrophysics Data System (ADS)

Novel InP/GaAs1-ySby/InP double-heterojunction bipolar transistors (HBTs) with a GaAs spacer between the InP emitter and GaAs1-ySby base layer were grown by the metalorganic chemical vapor deposition method in order to simplify the switching sequence for forming a high-quality InP-emitter/GaAs1-ySby-base interface. After removal of the InP emitter, the top surface of the GaAs spacer exhibits smooth step-flow-like morphology with root-mean-square roughness of 0.17-0.36 nm, whereas the morphology of the GaAs1-ySby base of the sample without the GaAs spacer is bumpy. Secondary ion mass spectroscopy reveals that the spacer suppresses the incorporation of excess Sb into the InP emitter around the emitter-base junction. The dependence of the current gain on the thickness of the GaAs spacer is investigated and, when the GaAs spacer is 2 nm, the highest current gain is obtained. Therefore, we employ the spacer to scaled-down HBTs with a 0.25-?m-wide emitter. The scaled-down HBTs show high current gain of over 90 at collector current density JC of 10 mA/?m2 even though the space between emitter and base electrodes is just 0.15 ?m. We obtain peak current-gain cut-off frequency of 388 GHz and peak maximum oscillation frequency of 290 GHz at JC=10 mA/?m2. This result suggests that the presence of the GaAs spacer does not impose any penalty on the characteristics at high JC. The insertion of the GaAs spacer is a good way to obtain a high-quality E-B interface with a simple precursor-supply sequence and thereby HBTs with both high-current gain and reasonably high RF performance.

Hoshi, Takuya; Kashio, Norihide; Sugiyama, Hiroki; Yokoyama, Haruki; Kurishima, Kenji; Ida, Minoru; Matsuzaki, Hideaki; Kohtoku, Masaki

2014-06-01

162

Molecular-beam epitaxial growth of InAs\\/GaAs superlattices on GaAs substrates and its application to a superlattice channel modulation-doped field-effect transistor  

Microsoft Academic Search

The molecular-beam epitaxial growth conditions for (InAs)m(GaAs)n short period superlattices (SPSs) on GaAs substrates have been optimized by monitoring reflection high-energy electron diffraction (RHEED) intensity oscillations. The RHEED oscillation measurements enable understanding InAs growth behavior on a 7% lattice-mismatch GaAs substrate. Within one monolayer InAs deposition with lower than 560 °C growth temperature can give high SPS crystalline quality. The

H. Toyoshima; K. Onda; E. Mizuki; N. Samoto; M. Kuzuhara; T. Itoh; A. Okamoto; T. Anan; T. Ichihashi

1991-01-01

163

Cryogenic measurements of aerojet GaAs n-JFETs  

NASA Technical Reports Server (NTRS)

The spectral noise characteristics of Aerojet gallium arsenide (GaAs) junction field effect transistors (JFET's) have been investigated down to liquid-helium temperatures. Noise characterization was performed with the field effect transistor (FET) in the floating-gate mode, in the grounded-gate mode to determine the lowest noise readings possible, and with an extrinsic silicon photodetector at various detector bias voltages to determine optimum operating conditions. The measurements indicate that the Aerojet GaAs JFET is a quiet and stable device at liquid helium temperatures. Hence, it can be considered a readout line driver or infrared detector preamplifier as well as a host of other cryogenic applications. Its noise performance is superior to silicon (Si) metal oxide semiconductor field effect transistor (MOSFET's) operating at liquid helium temperatures, and is equal to the best Si n channel junction field effect transistor (n-JFET's) operating at 300 K.

Goebel, John H.; Weber, Theodore T.

1993-01-01

164

K-band double-balanced mixer using GaAs HBT THz Schottky diodes  

Microsoft Academic Search

We report on a K-band double-balanced mixer using Schottky diodes made with our baseline (Foundry) GaAs HBT technology. The GaAs HBT MBE structure which yields a transistor fmax of 50 GHz, can also support Schottky diode structures with THz cut-off frequencies. A GaAs HBT Schottky diode double-balanced mixer achieves an upconversion loss of less than 6 dB over an RF

K. W. Kobayashi; R. Kasody; A. K. Oki; S. Dow; B. Allen; D. C. Streit

1994-01-01

165

Method for double-sided processing of thin film transistors  

DOEpatents

This invention provides methods for fabricating thin film electronic devices with both front- and backside processing capabilities. Using these methods, high temperature processing steps may be carried out during both frontside and backside processing. The methods are well-suited for fabricating back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.

Yuan, Hao-Chih (Madison, WI); Wang, Guogong (Madison, WI); Eriksson, Mark A. (Madison, WI); Evans, Paul G. (Madison, WI); Lagally, Max G. (Madison, WI); Ma, Zhenqiang (Middleton, WI)

2008-04-08

166

Bipolar battery  

DOEpatents

A bipolar battery having a plurality of cells. The bipolar battery includes: a negative electrode; a positive electrode and a separator element disposed between the negative electrode and the positive electrode, the separator element electrically insulating the electrodes from one another; an electrolyte disposed within at least one of the negative electrode, the positive electrode and the separator element; and an electrode containment structure including a cup-like electrode holder.

Kaun, Thomas D. (New Lenox, IL)

1992-01-01

167

Application of the Johnson criteria to graphene transistors  

NASA Astrophysics Data System (ADS)

For 60 years, the Johnson criteria have guided the development of materials and the materials choices for field-effect and bipolar transistor technology. Intrinsic graphene is a semi-metal, precluding transistor applications, but only under lateral bias is a gap opened and transistor action possible. This first application of the Johnson criteria to biased graphene suggests that this material will struggle to ever achieve competitive commercial applications.

Kelly, M. J.

2013-12-01

168

Modeling of single-event upset in bipolar integrated circuits  

NASA Technical Reports Server (NTRS)

The results of work done on the quantitative characterization of single-event upset (SEU) in bipolar random-access memories (RAMs) have been obtained through computer simulation of SEU in RAM cells that contain circuit models for bipolar transistors. The models include current generators that emulate the charge collected from ion tracks. The computer simulation results are compared with test data obtained from a RAM in a bipolar microprocessor chip. This methodology is applicable to other bipolar integrated circuit constructions in addition to RAM cells.

Zoutendyk, J. A.

1983-01-01

169

Radiation effects on JFETs (Junction Field-Effect Transistors), MOSFETs, and dipolar transistors, as related to SSC circuit design  

NASA Astrophysics Data System (ADS)

Some results of radiation effects on selected junction field-effect transistors, MOS field-effect transistors, and bipolar junction transistors are presented. The evaluations include dc parameters, as well as capacitive variations and noise evaluations. The tests are made at the low current and voltage levels (in particular, at currents less or equal to 1 mA) that are essential for the low-power regimes required by SSC circuitry. Detailed noise data are presented both before and after 5-Mrad (gamma) total-dose exposure. SPICE radiation models for three high-frequency bipolar processes are compared for a typical charge-sensitive preamplifier.

Kennedy, E. J.; Alley, G. T.; Britton, C. L., Jr.; Skubic, P. L.; Gray, B.; Wu, A.

1990-10-01

170

Developing Low-Noise GaAs JFETs For Cryogenic Operation  

NASA Technical Reports Server (NTRS)

Report discusses aspects of effort to develop low-noise, low-gate-leakage gallium arsenide-based junction field-effect transistors (JFETs) for operation at temperature of about 4 K as readout amplifiers and multiplexing devices for infrared-imaging devices. Transistors needed to replace silicon transistors, relatively noisy at 4 K. Report briefly discusses basic physical principles of JFETs and describes continuing process of optimization of designs of GaAs JFETs for cryogenic operation.

Cunningham, Thomas J.

1995-01-01

171

Magnetic vortex based transistor operations.  

PubMed

Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fan-out operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT). PMID:24531235

Kumar, D; Barman, S; Barman, A

2014-01-01

172

Magnetic Vortex Based Transistor Operations  

PubMed Central

Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fan–out operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT). PMID:24531235

Kumar, D.; Barman, S.; Barman, A.

2014-01-01

173

Magnetic Vortex Based Transistor Operations  

NASA Astrophysics Data System (ADS)

Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fan-out operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT).

Kumar, D.; Barman, S.; Barman, A.

2014-02-01

174

technologie transistor.  

E-print Network

�léments de technologie Les circuits intégrées c-MOS. L'élément de base est le transistor. Deux types de transistors complémentaires n-MOS et p-MOS. Avantages des c-MOS : #21; très grande intégration des impuretés. - plus récement : bombardement ionique. 2 #12; Transistor n-MOS (Metal

Hivert, Florent

175

Bipolar Disorder  

MedlinePLUS

... should I do if I start thinking about suicide? Source Management of Bipolar Disorder by KS Griswold, M.D., M.P.H. and LF Pessar, M.D. (American Family Physician September 15, 2000, http://www.aafp.org/ ...

176

Bipolar Disorder  

MedlinePLUS

... feeling is called mania. The down feeling is depression. The causes of bipolar disorder aren't always clear. It ... checkup can rule out other illnesses that might cause your mood ... even suicide. However, there are effective treatments to control symptoms: ...

177

Bipolar Disorder  

MedlinePLUS

... the juvenile justice system, abusing drugs, or committing suicide. Because children and teens with bipolar disorder do not usually show the ... 2012 Back 1 ? 2 ? 3 ? 4 ? 5 For Teens For Kids For Parents MORE ON THIS TOPIC When Depression Is Severe Suicide Why Do People Get Depressed? Can I Get ...

178

Bipolar-Battery Construction  

NASA Technical Reports Server (NTRS)

Bipolar batteries fabricated in continuous quasi-automated process. Components of battery configured so processing steps run sequentially. Key components of battery, bipolar plate and bipolar separator, fabricated separately and later joined together.

Rippel, Wally E.; Edwards, Dean B.

1988-01-01

179

Poly emitter bipolar hot carrier effects in an advanced BiCMOS technology  

Microsoft Academic Search

Hot carrier effects due to reverse biasing of emitter-base junction in a poly emitter bipolar transistor are discussed. Degradation of transistor current gain under DC, pulsed DC and AC stress conditions is found to be determined by the total injected charge through the reverse biased junction. These results coupled with the design simulations are used to predict the reliability of

S. P. Joshi; R. Lahri; C. Lage

1987-01-01

180

Screening for Bipolar Disorder  

Microsoft Academic Search

Bipolar disorder is a recurrent and some- times chronic illness involving episodes of depression and mania or hypomania. The most frequent presentation is depression: more than 1 of 5 primary care patients with depression have bipolar disorder. The symptoms of bipolar depres- sion often differ from those of unipolar depression. Age of onset for bipolar disorder is usually the late

A. L. Brickman

2002-01-01

181

Graphical design and iterative analysis of the DC parameters of GaAs FET's  

Microsoft Academic Search

Two-dimensional numerical solutions of Poisson's equation and the carrier continuity equation for the short-gate GaAS field-effect transistor structure have been used to predict device performance. However, a generally accepted simplified approach to FET design has not evolved. In this paper, a simplified design technique and an iterative device analysis procedure are presented for application to GaAs FET's with gate lengths

R. B. Fair

1974-01-01

182

New Gate Dielectric Oxides for GaAs and Other Semiconductors  

Microsoft Academic Search

It is well known that electrons move much faster in GaAs than in Si, and this attribute makes the GaAs-based metal oxide semiconductor field effect transistors (MOSFETs) very attractive for high-frequency, high-speed circuits applications. However, identifying a proper insulating oxide for GaAs has been a problem puzzling researchers over 35 years. Recently we discovered that the use of a mixed

M. Hong

2000-01-01

183

Two-dimensional carrier flow in a transistor structure under nonisothermal conditions  

Microsoft Academic Search

A two-dimensional mathematical model is developed to predict the internal behavior of power transistors operating under steady-state conditions. This model includes the internal self-heating effects in power transistors and is applicable to predict the transistor behavior under high-current and high-voltage operating conditions. The complete set of partial differential equations governing the bipolar semiconductor device behavior under nonisothermal conditions is solved

S. P. Gaur; D. H. Navon

1976-01-01

184

positions): transistor,  

E-print Network

scientists of the century'' (20 positions): . Technology � 6 (airplane, rocket, TV, transistor, plastic, WWW project: ''The greatest scientists of the century'' (20 positions): . Technology � 6 (airplane, rocket, TV unfriendly! #12; Why is excessive coding so bad for specific tasks? E#ciency is lost, which makes

Artemov, Sergei N.

185

Switching Transistor  

NASA Technical Reports Server (NTRS)

Westinghouse Electric Corporation's D60T transistors are used primarily as switching devices for controlling high power in electrical circuits. It enables reduction in the number and size of circuit components and promotes more efficient use of energy. Wide range of application from a popcorn popper to a radio frequency generator for solar cell production.

1981-01-01

186

A Heteroepitaxial Perovskite Metal-Base Transistor  

SciTech Connect

'More than Moore' captures a concept for overcoming limitations in silicon electronics by incorporating new functionalities in the constituent materials. Perovskite oxides are candidates because of their vast array of physical properties in a common structure. They also enable new electronic devices based on strongly-correlated electrons. The field effect transistor and its derivatives have been the principal oxide devices investigated thus far, but another option is available in a different geometry: if the current is perpendicular to the interface, the strong internal electric fields generated at back-to-back heterojunctions can be used for oxide electronics, analogous to bipolar transistors. Here we demonstrate a perovskite heteroepitaxial metal-base transistor operating at room temperature, enabled by interface dipole engineering. Analysis of many devices quantifies the evolution from hot-electron to permeable-base behaviour. This device provides a platform for incorporating the exotic ground states of perovskite oxides, as well as novel electronic phases at their interfaces.

Yajima, T.; Hikita, Y.; /Tokyo U.; Hwang, H.Y.; /Tokyo U. /JST, PRESTO /SLAC; ,

2011-08-11

187

Bipolar disorder: diagnostic issues  

Microsoft Academic Search

Bipolar disorders are cyclical mood disorders with clinical features including distinct sustained periods of mood elevation. • Briefer (4 days or more), mild episodes of mood elevation define bipolar II disorder; lengthier (7 days or more), more severe episodes (or those requiring hospitalisation), with or without psychotic features, define bipolar I disorder. • Depressive periods are more common and lengthier

John W G Tiller; Isaac Schweitzer

2010-01-01

188

Analysis and Design of a Gated Envelope Feedback Technique for Automatic Hardware Reconfiguration of RFIC Power Amplifiers, with Full On-Chip Implementation in Gallium Arsenide Heterojunction Bipolar Transistor Technology  

NASA Astrophysics Data System (ADS)

In this doctoral dissertation, the author presents the theoretical foundation, the analysis and design of analog and RF circuits, the chip level implementation, and the experimental validation pertaining to a new radio frequency integrated circuit (RFIC) power amplifier (PA) architecture that is intended for wireless portable transceivers. A method called Gated Envelope Feedback is proposed to allow the automatic hardware reconfiguration of a stand-alone RFIC PA in multiple states for power efficiency improvement purposes. The method uses self-operating and fully integrated circuitry comprising RF power detection, switching and sequential logic, and RF envelope feedback in conjunction with a hardware gating function for triggering and activating current reduction mechanisms as a function of the transmitted RF power level. Because of the critical role that RFIC PA components occupy in modern wireless transceivers, and given the major impact that these components have on the overall RF performances and energy consumption in wireless transceivers, very significant benefits stem from the underlying innovations. The method has been validated through the successful design of a 1.88GHz COMA RFIC PA with automatic hardware reconfiguration capability, using an industry renowned state-of-the-art GaAs HBT semiconductor process developed and owned by Skyworks Solutions, Inc., USA. The circuit techniques that have enabled the successful and full on-chip embodiment of the technique are analyzed in details. The IC implementation is discussed, and experimental results showing significant current reduction upon automatic hardware reconfiguration, gain regulation performances, and compliance with the stringent linearity requirements for COMA transmission demonstrate that the gated envelope feedback method is a viable and promising approach to automatic hardware reconfiguration of RFIC PA's for current reduction purposes. Moreover, in regard to on-chip integration of advanced PA control functions, it is demonstrated that the method is better positioning GaAs HBT technologies, which are known to offer very competitive RF performances but inherently have limited integration capabilities. Finally, an analytical approach for the evaluation of inter-modulation distortion (IMD) in envelope feedback architectures is introduced, and the proposed design equations and methodology for IMD analysis may prove very helpful for theoretical analyses, for simulation tasks, and for experimental work.

Constantin, Nicolas Gerard David

189

AC performance of nanoelectronics: towards a ballistic THz nanotube transistor  

NASA Astrophysics Data System (ADS)

We present phenomenological predictions for the cutoff frequency of carbon nanotube transistors. We also present predictions of the effects parasitic capacitances on AC nanotube transistor performance. The influence of quantum capacitance, kinetic inductance, and ballistic transport on the high-frequency properties of nanotube transistors is analyzed. We discuss the challenges of impedance matching for ac nano-electronics in general, and show how integrated nanosystems can solve this challenge. Our calculations show that carbon nano-electronics may be faster than conventional Si, SiGe, GaAs, or InP semiconductor technologies. We predict a cutoff frequency of 80 GHz/ L, where L is the gate length in microns, opening up the possibility of a ballistic THz nanotube transistor.

Burke, Peter J.

2004-11-01

190

Breakdown in millimeter-wave power InP HEMTs: a comparison with GaAs PHEMT's  

Microsoft Academic Search

In spite of their outstanding transport characteristics, InP high-electron mobility transistors (HEMTs) deliver lower output power than GaAs pseudomorphic HEMTs (PHEMTs) throughout most of the millimeter-wave regime. However, the superior power-added efficiency of InP HEMTs when compared with GaAs PHEMTs makes this technology attractive for many applications. The reason for the relatively inferior power output of InP HEMTs lies in

J. A. del Alamo; M. H. Somerville

1999-01-01

191

InP Bipolar ICs: Scaling Roadmaps, Frequency Limits, Manufacturable Technologies  

Microsoft Academic Search

Indium phosphide heterojunction bipolar transistors (HBTs) find applications in very wide-band digital and mixed-signal integrated circuits (ICs). Devices fabricated in high-yield process flows at 500 nm feature size obtain 450 GHz cutoff frequencies and 5 V breakdown and enable high yield fabrication of integrated circuits having more than 3000 transistors. Laboratory devices at 250 nm feature size obtain 755 GHz

Mark J. W. Rodwell; Minh Le; Berinder Brar

2008-01-01

192

Simultaneous single event charge sharing and parasitic bipolar conduction in a highly-scaled SRAM design  

Microsoft Academic Search

A novel mechanism for upset is seen in a commercially available 0.25 ?m 10-T SEE hardened SRAM cell. Unlike traditional multiple node charge collection in which diffusions near a single event strike collect the deposited carriers, this new mechanism involves direct drift-diffusion collection at an NFET transistor in conjunction with parasitic bipolar conduction in nearby PFET transistors. The charge collection

Brian D. Olson; Dennis R. Ball; Kevin M. Warren; Lloyd W. Massengill; Nadim F. Haddad; Scott E. Doyle; Dale McMorrow

2005-01-01

193

Experimental determination of single-event upset (SEU) as a function of collected charge in bipolar integrated circuits  

NASA Technical Reports Server (NTRS)

Single-Event Upset (SEU) in bipolar integrated circuits (ICs) is caused by charge collection from ion tracks in various regions of a bipolar transistor. This paper presents experimental data which have been obtained wherein the range-energy characteristics of heavy ions (Br) have been utilized to determine the cross section for soft-error generation as a function of charge collected from single-particle tracks which penetrate a bipolar static RAM. The results of this work provide a basis for the experimental verification of circuit-simulation SEU modeling in bipolar ICs.

Zoutendyk, J. A.; Malone, C. J.; Smith, L. S.

1984-01-01

194

Bipolar disorder in youth  

Microsoft Academic Search

The debate regarding the possible existence of prepubertal bipolar illness has surfaced at various points in history. In its\\u000a most recent incarnation, proponents of a childhood bipolar diagnosis argue that there is an early-onset form of bipolar illness\\u000a that is highly comorbid and characterized by simultaneous irritability and depression. Others have suggested that childhood\\u000a manic symptoms are more likely a

Gabrielle A. Carlson; Stephanie E. Meyer

2000-01-01

195

Sub20 ps silicon bipolar technology using selective epitaxial growth  

Microsoft Academic Search

A sub-20 ps silicon bipolar technology has been developed using selective epitaxial growth (SEG) for the active base and collector regions. This transistor concept allows the simultaneous reduction of base width and base\\/collector capacitance while maintaining low extrinsic base resistance. At a current of 0.8 mA a record CML gate delay time of 18 ps is achieved with devices showing

T. F. Meister; R. Stengl; H. W. Meul; R. Weyl; P. Packan; A. Felder; H. Klose; R. Schreiter; J. Popp; H. M. Rein; L. Treitinger

1992-01-01

196

Forward-bias tunneling: A limitation to bipolar device scaling  

Microsoft Academic Search

Forward-bias tunneling is observed in heavily doped p-n junctions of bipolar transistors. A simple phenomenological model suitable to incorporation in device codes is developed. The model identifies as key parameters the space-charge-region (SCR) thickness at zero bias and the reduced doping level at its edges which can both be obtained from CV characteristics. This tunneling mechanism may limit the maximum

JESUS A. DEL ALAMO; RICHARD M. SWANSON

1986-01-01

197

A silicon nanocrystal tunnel field effect transistor  

NASA Astrophysics Data System (ADS)

In this work, we demonstrate a silicon nanocrystal Field Effect Transistor (ncFET). Its operation is similar to that of a Tunnelling Field Effect Transistor (TFET) with two barriers in series. The tunnelling barriers are fabricated in very thin silicon dioxide and the channel in intrinsic polycrystalline silicon. The absence of doping eliminates the problem of achieving sharp doping profiles at the junctions, which has proven a challenge for large-scale integration and, in principle, allows scaling down the atomic level. The demonstrated ncFET features a 104 on/off current ratio at room temperature, a low 30 pA/?m leakage current at a 0.5 V bias, an on-state current on a par with typical all-Si TFETs and bipolar operation with high symmetry. Quantum dot transport spectroscopy is used to assess the band structure and energy levels of the silicon island.

Harvey-Collard, Patrick; Drouin, Dominique; Pioro-Ladrière, Michel

2014-05-01

198

Outlook and emerging semiconducting materials for ambipolar transistors.  

PubMed

Ambipolar or bipolar transistors are transistors in which both holes and electrons are mobile inside the conducting channel. This device allows switching among several states: the hole-dominated on-state, the off-state, and the electron-dominated on-state. In the past year, it has attracted great interest in exotic semiconductors, such as organic semiconductors, nanostructured materials, and carbon nanotubes. The ability to utilize both holes and electrons inside one device opens new possibilities for the development of more compact complementary metal-oxide semiconductor (CMOS) circuits, and new kinds of optoelectronic device, namely, ambipolar light-emitting transistors. This progress report highlights the recent progresses in the field of ambipolar transistors, both from the fundamental physics and application viewpoints. Attention is devoted to the challenges that should be faced for the realization of ambipolar transistors with different material systems, beginning with the understanding of the importance of interface modification, which heavily affects injections and trapping of both holes and electrons. The recent development of advanced gating applications, including ionic liquid gating, that open up more possibility to realize ambipolar transport in materials in which one type of charge carrier is highly dominant is highlighted. Between the possible applications of ambipolar field-effect transistors, we focus on ambipolar light-emitting transistors. We put this new device in the framework of its prospective for general lightings, embedded displays, current-driven laser, as well as for photonics-electronics interconnection. PMID:24591008

Bisri, Satria Zulkarnaen; Piliego, Claudia; Gao, Jia; Loi, Maria Antonietta

2014-02-26

199

Gated Conductance of Thin Indium Tin Oxide - The Simplest Transistor  

E-print Network

Transistors are the fundamental building block of modern electronic devices. So far, all transistors are based on various types of semiconductor junctions. The most common bipolar-junction transistors and metal-oxide-semiconductor field-effect transistors contain p-n junctions to control the current, depending on applied biases across the junctions. Thin-film transistors need metal-semiconductor junctions for injecting and extracting electrons from their channels. Here, by coating a heavily-doped thin indium-tin-oxide (ITO) film through a shadow mask onto a biopolymer chitosan/ITO/glass substrate, we can have a high-performance junctionless transparent organic-inorganic hybrid thin film transistor. This could be the simplest transistor in the world, to our knowledge, not only in its structure, but also its fabrication process. In addition, the device performance is found to be greatly enhanced using a reinforced chitosan/SiO2 hybrid bilayer dielectric stack. Our results clearly show that this architecture can...

Jiang, Jie; Sun, Jia; Dou, Wei; Zhang, Qing

2012-01-01

200

Actigraphy in Remitted Bipolar Patients SLEEP IN REMITTED BIPOLAR DISORDER  

E-print Network

Actigraphy in Remitted Bipolar Patients 1 SLEEP IN REMITTED BIPOLAR DISORDER: A NATURALISTIC CASE euthymic BD cases from HC. 6 keywords: bipolar disorder; actigraphy; euthymia; remission; sleep; circadian Bipolar disorder (BD) is a severe mental disorder and the worldwide prevalence of the BD spectrum is 1

Boyer, Edmond

201

Time-dependent carrier flow in a transistor structure under nonisothermal conditions  

Microsoft Academic Search

A time-dependent temperature-dependent two-dimensional model has been developed to illustrate the internal behavior of bipolar transistors. Electrothermal interactions within the device are calculated in an attempt to better understand thermal instability modes. Numerically computed results are presented showing the electrical and thermal effects in the transistor operating in the switching mode during turn-on along a resistive load line. Plots of

V. C. Alwin; D. H. Navon; L. J. Turgeon

1977-01-01

202

Creativity in familial bipolar disorder  

Microsoft Academic Search

Studies have demonstrated relationships between creativity and bipolar disorder (BD) in individuals, and suggested familial transmission of both creativity and BD. However, to date, there have been no studies specifically examining creativity in offspring of bipolar parents and clarifying mechanisms of intergenerational transmission of creativity. We compared creativity in bipolar parents and their offspring with BD and bipolar offspring with

Diana I. Simeonova; Kiki D. Chang; Connie Strong; Terence A. Ketter

2005-01-01

203

Novel techniques for the fabricating and characterization of GaAs MIS (Metal Insulator Semiconductor) structures  

NASA Astrophysics Data System (ADS)

Organometallic chemical vapor deposition (OMCVD) of Al2O3 on GaAs has been investigated as a means of fabricating metal-insulator-semiconductor field effect transistors (MISFET). Deposition at temperatures less than 400C forms high-quality films of Al2O3. Diffusion can alter the composition during high-temperature anneals. In-situ etching of the GaAs just prior to depositing the Al2O3 markedly reduced surface generation velocities, but inversion at the interface was not conclusively demonstrated.

Ehle, R. S.; Morris, W. G.; Baliga, B. J.

1984-06-01

204

A 600-MHz median-type digital filter on GaAs  

NASA Technical Reports Server (NTRS)

A single-chip GaAs implementation of an FIR-median hybrid filter is presented. The very high-speed digital filter combines linear averaging structures to a median selector. The filter operates on 5-b samples with ECL-compatible I/O interfaces. The 1500-transistor LSI device with 3.6-sq mm chip size was processed with a 1.0-micron GaAs depletion-mode (D-mode) MESFET process. The filter demonstrates 600-MHz sample rate when operated in test mode utilizing special built-in feedback.

Vainjo, Olli; Sundaram, Mani; Long, Stephen I.; Neuvo, Yrjo

1992-01-01

205

Investigation of irradiated monolithic transistors for space applications  

NASA Astrophysics Data System (ADS)

In this paper experimental results on radiation effects on a BICMOS high speed commercial technology, manufactured by STMicroelectronics, are reported. Bipolar transistors were irradiated by neutrons, ions, or by both of them. Fast neutrons, as well as other types of particles, produce defects, mainly by displacing silicon atoms from their lattice positions to interstitial locations, i.e. generating vacancy-interstitial pairs, the so-called Frenkel pairs (FP). Defects introduce trapping energy states which degrade the common emitter current gain ?. The gain degradation has been investigated for collector current Ic between 1 ?A and 1 mA. It was found a linear dependence of ?(1/ ?)=1/ ?i-1/ ? (where ?i and ? are the gain after and before the irradiation) as a function of the concentration of FP. The bipolar transistors made on this technology have shown to be particularly radiation resistant. Both base and collector currents have been also systematically investigated.

Codegoni, D.; Colder, A.; Croitoru, N.; D'Angelo, P.; DeMarchi, M.; Fallica, G.; Favalli, A.; Leonardi, S.; Levalois, M.; Marie, P.; Modica, R.; Rancoita, P. G.; Seidman, A.

2004-03-01

206

Bipolar Disorder in Children  

PubMed Central

Although bipolar disorder historically was thought to only occur rarely in children and adolescents, there has been a significant increase in children and adolescents who are receiving this diagnosis more recently (Carlson, 2005). Nonetheless, the applicability of the current bipolar disorder diagnostic criteria for children, particularly preschool children, remains unclear, even though much work has been focused on this area. As a result, more work needs to be done to further the understanding of bipolar symptoms in children. It is hoped that this paper can assist psychologists and other health service providers in gleaning a snapshot of the literature in this area so that they can gain an understanding of the diagnostic criteria and other behaviors that may be relevant and be informed about potential approaches for assessment and treatment with children who meet bipolar disorder criteria. First, the history of bipolar symptoms and current diagnostic criteria will be discussed. Next, assessment strategies that may prove helpful for identifying bipolar disorder will be discussed. Then, treatments that may have relevance to children and their families will be discussed. Finally, conclusions regarding work with children who may have a bipolar disorder diagnosis will be offered. PMID:24800202

2014-01-01

207

Transistors: The Field Effect  

NSDL National Science Digital Library

Transistors are the building blocks of modern electronic devices. Your cell phones, iPods, and computers all depend on them to operate. Thanks to today's microfabrication technology, transistors can be made very tiny and be massively produced. You are probably using billions of them while working with this activity now--as of 2006, a dual-core Intel microprocessor contains 1.7 billion transistors. The field effect transistor is the most common type of transistor. So we will focus on it in this activity.

Consortium, The C.

2011-12-11

208

The model and optimisation of structure of power integrated pulse transistor (in Ukrainian)  

NASA Astrophysics Data System (ADS)

A model describing the mode of transition to the ohm quasi--saturation in the collector of power integrated bipolar transistors the special features of which is the irregularity of distributed resistance of the collector part, is proposed. The questions of optimisation of topology of power integrated pulse transistors that work in the mode of great relative pulse duration of short pulses with insignificant heat release are considered. The optimisation allows to make a choice of the construction and determine the geometrical dimensions of integrated transistor structure which is characterized by the minimum values of output capacity and resistance of the collector.

Smerklo, L. M.

209

Genetics of bipolar disorder.  

PubMed

Studies of families and twins show the importance of genetic factors affecting susceptibility to bipolar disorder and suggest substantial genetic and phenotypic complexity. Robust and replicable genome-wide significant associations have recently been reported in genome-wide association studies at several common polymorphisms, including variants within the genes CACNA1C, ODZ4, and NCAN. Strong evidence exists for a polygenic contribution to risk (ie, many risk alleles of small effect). A notable finding is the overlap of susceptibility between bipolar disorder and schizophrenia for several individual risk alleles and for the polygenic risk. By contrast, genomic structural variation seems to play a smaller part in bipolar disorder than it does in schizophrenia. Together, these genetic findings suggest directions for future studies to delineate the aetiology and pathogenesis of bipolar disorder, indicate the need to re-evaluate our diagnostic classifications, and might eventually pave the way for major improvements in clinical management. PMID:23663951

Craddock, Nick; Sklar, Pamela

2013-05-11

210

Bipolar thermoelectric devices  

E-print Network

The work presented here is a theoretical and experimental study of heat production and transport in bipolar electrical devices, with detailed treatment of thermoelectric effects. Both homojunction and heterojunction devices ...

Pipe, Kevin P. (Kevin Patrick), 1976-

2004-01-01

211

A self-aligned emitter base NiSi electrode technology for advanced high-speed bipolar LSIs  

Microsoft Academic Search

The characteristics of double polysilicon self-aligned bipolar transistors with advanced 0.4-?m NiSi salicide base electrodes are reported. Since NiSi\\/polysilicon contact resistance is lower than that of TiSi2\\/polysilicon and the process temperature is lower, the result is a high-performance bipolar device. A very low base resistance of 91 ? was obtained

T. Iinuma; N. Itoh; K. Inou; H. Nakajima; S. Matsuda; I. Kunishima; K. Suguro; Y. Katsumata; H. Iwai

1992-01-01

212

Study of bipolar batteries  

Microsoft Academic Search

The status of development of bipolar batteries with an aqueous electrolyte was determined. Included in the study were lead-acid, nickel-cadmium, nickel-zinc, nickel-iron, and nickel-hydrogen batteries. The technical and patent literature is reviewed and a bibliography covering the past 15 years is presented. Literature data are supplemented by a survey of organizations. The principal interest was in bipolar lead-acid batteries and

J. E. Clifford

1984-01-01

213

Staging Bipolar Disorder  

Microsoft Academic Search

The purpose of this study was to analyze the evidence supporting a staging model for bipolar disorder. The authors conducted\\u000a an extensive Medline and Pubmed search of the published literature using a variety of search terms (staging, bipolar disorder,\\u000a early intervention) to find relevant articles, which were reviewed in detail. Only recently specific proposals have been made\\u000a to apply clinical

Eduard Vieta; M. Reinares; A. R. Rosa

2011-01-01

214

Radiation effect on silicon transistors in mixed neutrons-gamma environment  

NASA Astrophysics Data System (ADS)

The effects of gamma and neutron irradiations on two different types of transistors, Junction Field Effect Transistor (JFET) and Bipolar Junction Transistor (BJT), were investigated. Irradiation was performed using a Syrian research reactor (RR) (Miniature Neutron Source Reactor (MNSR)) and a gamma source (Co-60 cell). For RR irradiation, MCNP code was used to calculate the absorbed dose received by the transistors. The experimental results showed an overall decrease in the gain factors of the transistors after irradiation, and the JFETs were more resistant to the effects of radiation than BJTs. The effect of RR irradiation was also greater than that of gamma source for the same dose, which could be because neutrons could cause more damage than gamma irradiation.

Assaf, J.; Shweikani, R.; Ghazi, N.

2014-10-01

215

Temperature dependence of electronic behaviors in quantum dimension junctionless thin-film transistor  

NASA Astrophysics Data System (ADS)

The high temperature dependence of junctionless (JL) gate-all-around (GAA) poly-Si thin-film transistors (TFTs) with 2-nm-thick nanosheet channel is compared with that of JL planar TFTs. The variation of SS with temperature for JL GAA TFTs is close to the theoretical value (0.2 mV/dec/K), owing to the oxidation process to form a 2-nm-thick channel. The bandgap of 1.35 eV in JL GAA TFTs by fitting experimental data exhibits the quantum confinement effect, indicating greater suppression of Ioff than that in JL planar TFTs. The measured [InlineEquation not available: see fulltext.] of -1.34 mV/°C in JL GAA nanosheet TFTs has smaller temperature dependence than that of -5.01 mV/°C in JL planar TFTs.

Cheng, Ya-Chi; Chen, Hung-Bin; Han, Ming-Hung; Lu, Nan-Heng; Su, Jun-Ji; Shao, Chi-Shen; Wu, Yung-Chun

2014-08-01

216

A transistor based air flow transducer for thermohygrometric control of neonatal ventilatory applications  

Microsoft Academic Search

An air flow transducer for controlling heated humidifiers used in neonatal artificial ventilation, suitable for in-line application in monopatient breathing circuits, is described here. The sensor is built with two nominally identical bipolar junction transistors, with different packages, as hot elements operated at a regulated constant voltage. The operation principle is based on the differential convective heat power exchanged with

Emiliano Schena; Sergio Silvestri

2008-01-01

217

Genetics of bipolar disorder  

PubMed Central

Bipolar disorder (also known as manic depressive illness) is a complex genetic disorder in which the core feature is pathological disturbance in mood (affect) ranging from extreme elation, or mania, to severe depression usually accompanied by disturbances in thinking and behaviour. The lifetime prevalence of 1% is similar in males and females and family, twin, and adoption studies provide robust evidence for a major genetic contribution to risk. There are methodological impediments to precise quantification, but the approximate lifetime risk of bipolar disorder in relatives of a bipolar proband are: monozygotic co-twin 40-70%; first degree relative 5-10%; unrelated person 0.5-1.5%. Occasional families may exist in which a single gene plays the major role in determining susceptibility, but the majority of bipolar disorder involves the interaction of multiple genes (epistasis) or more complex genetic mechanisms (such as dynamic mutation or imprinting). Molecular genetic positional and candidate gene approaches are being used for the genetic dissection of bipolar disorder. No gene has yet been identified but promising findings are emerging. Regions of interest identified in linkage studies include 4p16, 12q23-q24, 16p13, 21q22, and Xq24-q26. Chromosome 18 is also of interest but the findings are confusing with up to three possible regions implicated. To date most candidate gene studies have focused on neurotransmitter systems influenced by medication used in clinical management of the disorder but no robust positive findings have yet emerged. It is, however, almost certain that over the next few years bipolar susceptibility genes will be identified. This will have a major impact on our understanding of disease pathophysiology and will provide important opportunities to investigate the interaction between genetic and environmental factors involved in pathogenesis. This is likely to lead to major improvements in treatment and patient care but will also raise important ethical issues that will need to be addressed.???Keywords: bipolar disorder; manic depressive illness PMID:10465107

Craddock, N.; Jones, I.

1999-01-01

218

GaAs inverted common drain logic (ICDL) and its performance compared with other GaAs logic families  

NASA Astrophysics Data System (ADS)

An approach, which will be called inverted common drain logic (ICDL), to GaAs MESFET logic is considered, in which the logic functions are realized using the pull up rather than the pull down transistors which are normally used. Depletion ("normally on") transistors are employed. The basic switching modes and the advantages and problems are discussed. Experimental results confirming feasibility are then presented on circuits fabricated using a 2 ?m gate process using selective ion implantation directly into semi-insulating LEC GaAs. Simulations were done using both the JFET and the Sussman-Fort MESFET models in SPICE. Experimental results were first simulated using parametric data obtained from measurements on our own devices. In order to attempt to compare performance with some well established logic approaches, these were simulated using the same parametric data for all the logics. The data here were selected from published experimental results. We conclude that this logic approach may not be without advantages in some cases.

Abdel-Motaleb, Ibrahim M.; Rutherford, William C.; Young, Lawrence

1987-04-01

219

Neutron damage equivalence for silicon, silicon dioxide, and GaAs  

NASA Astrophysics Data System (ADS)

Displacement-energy and ionization-energy transfers to Si, SiO2, and GaAs as functions of incident neutron energy were calculated using cross-section data and fine group structure in the NJOY code system. Neutron spectra determinations for several reactor neutron environments were made using activation cross sections and a novel technique with the SAND II code. Measurements of carrier-removal rates in GaAs and of Si transistor gain degradation were made in representative neutron environments. Experimental results are compared to damage ratios predicted with the spectra and NJOY displacement functions. For fission-like spectra, calculated Si damage ratios are in good agreement with those determined with ASTM E722-85 and with measured transistor damage ratios. Significant differences are found between Si NJOY and ASTM E722-85 for 14-MeV-to-reactor neutron damage ratios; NJOY gives better agreement with experimental data reported in the literature. In GaAs, 14-MeV-to-reactor experimental damage ratios are smaller than predicted by calculated displacement ratios. This suggests that a more complex model of damage for majority carrier removal in GaAs is required. The use of incorrect damage functions is shown to adversely affect simulation fidelity in some representative neutron environments.

Luera, Theodore F.; Kelly, John G.; Stein, Herman J.; Lazo, Maximo S.; Lee, Clarence E.

1987-12-01

220

[Antipsychotics in bipolar disorders].  

PubMed

This article is a review of the various treatments that are currently available, in particular in France, for the treatment of bipolar disorders. This article specifically addresses the use of novel antipsychotic agents as alternative therapy to a lithium therapy and/or the use of conventional antipsychotics. The prevalence of bipolar disorder over a lifetime is around 1% of the general population. Bipolar disorder consists of alternating depressive and manic episodes. It mainly affects younger subjects, and is often associated with alcohol and drug addictions. There are two main subtypes of bipolar disorder. According to the DSM IV-R, type 1 of bipolar disorder is characterised when at least one manic episode (or a mixed episode) has been diagnosed. Type 2 of bipolar disorder is related to patients enduring recurrent depressive episodes but no manic episode. Type 2 affects women more frequently as opposed to type 1 affecting individuals of both sexes. Manic-depressive disorder (or cyclo-thymic disorder) appears in relation to patients who has never suffered manic episode, mixed episode or severe depressive episode but have undergone numerous periods with some symptoms of depression and hypomanic symptoms over a two-year period during which any asymptomatic periods last no longer than two months. The average age of the person going through a first episode (often a depressive one) is 20 years-old. Untreated bipolar patients may endure more than ten manic or depressive episodes. Finally, in relation to 10 to 20% of patients, the bipolar disorder will turn into a fast cycle form, either spontaneously or as a result of certain medical treatments. Psychiatrists are now able to initiate various treating strategies which are most likely to be effective as a result of the identification of clinical subtypes of the bipolar disorder. Lithium therapy has been effectively and acutely used for patients with pure or elated mania and its prophylaxis. However, lithium medication may worsen depressive symptoms when used for a long term maintenance therapy. Additionally, mixed mania, rapid cycling type patients and bipolar disorder associated with substance abuse do not respond well to lithium therapy. In addition to the lithium therapy or in place of a lithium therapy, one can report the frequent use of antipsychotic agents in respect of patients with bipolar disorder during both the acute and maintenance phases of treatment. Antipsychotic agents have been used for almost forty years and may be used in combination with a lithium therapy. Conventional antipsychotics are effective but they may induce late dyskinesia, weight gain, sedation, sexual dysfunction and depression. These adverse side effects often lead to non compliance in particular in circumstances where antipsychotic agents are combined with a lithium therapy. A number of alternative somatic treatment approaches have been reported for patients who do not respond well or who are intolerant to lithium therapy. As such, valproate has received regulatory approval for the acute treatment of mania and carbamazepine has been indicated for this condition in a number of countries. Divalproex (Depakote) has recently obtained the authorization to market in France and may be prescribed for manic states or hypomanic states that do not tolerate lithium therapy or for which lithium therapy is contraindicated. A number of other anticonvulsants (lamotrigine, gabapentin and topiramate) are currently being tested. Because of the side effects of the conventional antipsychotic agents, atypical antipsychotic agents are currently on trial and appear to be of interest in the treatment of bipolar disorders. Currently, a number of prospective studies are available with clozapine, risperidone and olanzapine in the treatment of bipolar disorder. Most are short-term studies. Recent randomised, double-blind, placebo-controlled studies have shown clozapine, risperidone and olanzapine to be effective with antimanic and antidepressive effects, both as monotherapy and as add-on maintenance therapy with lithium

Vacheron-Trystram, M-N; Braitman, A; Cheref, S; Auffray, L

2004-01-01

221

Transistor as a Rectifier  

E-print Network

Transistor is a three terminal semiconductor device normally used as an amplifier or as a switch. Here the alternating current (a.c) rectifying property of the transistor is considered. The ordinary silicon diode exhibits a voltage drop of ~0.6V across its terminals. In this article it is shown that the transistor can be used to build a diode or rectify low current a.c (~mA) with a voltage drop of ~0.03V. This voltage is ~20 times smaller than the silicon diode. This article gives the half-wave and full-wave transistor rectifier configurations along with some applications to justify their usefulness.

Raju Baddi

2012-04-09

222

Transistor as a Rectifier  

E-print Network

Transistor is a three terminal semiconductor device normally used as an amplifier or as a switch. Here the alternating current (a.c) rectifying property of the transistor is considered. The ordinary silicon diode exhibits a voltage drop of ~0.6V across its terminals. In this article it is shown that the transistor can be used to build a diode or rectify low current a.c (~mA) with a voltage drop of ~0.03V. This voltage is ~20 times smaller than the silicon diode. This article gives the half-wave and full-wave transistor rectifier configurations along with some applications to justify their usefulness.

Baddi, Raju

2012-01-01

223

Bipolar Affective Disorder and Migraine  

PubMed Central

This paper consists of a case history and an overview of the relationship, aetiology, and treatment of comorbid bipolar disorder migraine patients. A MEDLINE literature search was used. Terms for the search were bipolar disorder bipolar depression, mania, migraine, mood stabilizer. Bipolar disorder and migraine cooccur at a relatively high rate. Bipolar II patients seem to have a higher risk of comorbid migraine than bipolar I patients have. The literature on the common roots of migraine and bipolar disorder, including both genetic and neuropathological approaches, is broadly discussed. Moreover, bipolar disorder and migraine are often combined with a variety of other affective disorders, and, furthermore, behavioural factors also play a role in the origin and course of the diseases. Approach to treatment options is also difficult. Several papers point out possible remedies, for example, valproate, topiramate, which acts on both diseases, but no first-choice treatments have been agreed upon yet. PMID:22649454

Engmann, Birk

2012-01-01

224

Lightweight bipolar storage battery  

NASA Technical Reports Server (NTRS)

An apparatus [10] is disclosed for a lightweight bipolar battery of the end-plate cell stack design. Current flow through a bipolar cell stack [12] is collected by a pair of copper end-plates [16a,16b] and transferred edgewise out of the battery by a pair of lightweight, low resistance copper terminals [28a,28b]. The copper terminals parallel the surface of a corresponding copper end-plate [16a,16b] to maximize battery throughput. The bipolar cell stack [12], copper end-plates [16a,16b] and copper terminals [28a,28b] are rigidly sandwiched between a pair of nonconductive rigid end-plates [20] having a lightweight fiber honeycomb core which eliminates distortion of individual plates within the bipolar cell stack due to internal pressures. Insulating foam [30] is injected into the fiber honeycomb core to reduce heat transfer into and out of the bipolar cell stack and to maintain uniform cell performance. A sealed battery enclosure [ 22] exposes a pair of terminal ends [26a,26b] for connection with an external circuit.

Rowlette, John J. (Inventor)

1992-01-01

225

Design, Simulation and Modeling of Insulated Gate Bipolar Transistor  

E-print Network

device materials and structures. There are many types of power semiconductor devices available today. These include the thyristor, power MOSFET, power BJT, GTO, IGCT and IGBT. Our focus in this thesis is on IGBT and its advantages over other devices... characteristics and proposes a novel electro-thermal coupling simulation. However, the existing Verilog-A models are quite basic. The model by Lauritzen et al. is described in [8]. This basic Verilog-A model uses the lumped charge approach for easier parameter...

Gupta, Kaustubh

2013-07-09

226

Transmission resonances in the bipolar quantum resonant tunneling transistor  

E-print Network

?? (20) where a is the slope and n = 1, 2, . . . The energy at the top of a finite well with slope o and width Lw is E?= oLw. If we then approximate E?by the infinite well result (20), 34 the condition for a resonance, or expression for the slope as a... ?? (20) where a is the slope and n = 1, 2, . . . The energy at the top of a finite well with slope o and width Lw is E?= oLw. If we then approximate E?by the infinite well result (20), 34 the condition for a resonance, or expression for the slope as a...

Mondragon, Antonio Richard

2012-06-07

227

Clinical challenges of bipolar depression.  

PubMed

The observation that atypical antipsychotic drugs have some role in treating bipolar disorders has revived interest in the management of bipolar disorder. Given the prevalence of and the disability associated with bipolar depression, current medication is inadequate and new research to help patients with this condition is overdue. PMID:17974295

Pandarakalam, James Paul

2007-10-01

228

Epilepsy and bipolar disorders.  

PubMed

Although mood disorders represent a frequent psychiatric comorbidity among patients with epilepsy, data regarding bipolar disorders are still limited. However, these two conditions apparently share a number of biochemical and pathophysiological underpinnings, such as the kindling phenomenon, changes in neurotransmitters and modifications in voltage-opened ion channels and second messenger systems. Moreover, epilepsy and bipolar disorders are both episodic conditions with a time course of illness that can become chronic. Recent data suggest that mood instability is actually frequent among patients with epilepsy but is phenomenologically different from that described in bipolar disorder. The present paper reviews available evidence regarding such an intriguing comorbidity in order to discuss valuable clinical issues and to suggest novel therapeutic strategies. PMID:20021317

Mula, Marco; Marotta, Antonella Ester; Monaco, Francesco

2010-01-01

229

Bipolar battery construction  

NASA Technical Reports Server (NTRS)

A lightweight, bipolar battery construction for lead acid batteries in which a plurality of thin, rigid, biplates each comprise a graphite fiber thermoplastic composition in conductive relation to lead stripes plated on opposite flat surfaces of the plates, and wherein a plurality of nonconductive thermoplastic separator plates support resilient yieldable porous glass mats in which active material is carried, the biplates and separator plates with active material being contained and maintained in stacked assembly by axial compression of the stacked assembly. A method of assembling such a bipolar battery construction.

Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

1981-01-01

230

431 531 Class Notes 5 5 Transistors and Transistor Circuits  

E-print Network

431 531 Class Notes 5 5 Transistors and Transistor Circuits Although I will not follow the text in detail for the discussion of transistors, I will follow the text's philosophy. Unless one gets into device fabrication, it is generally not important to understand the inner workings of transistors

Frey, Raymond E.

231

Microwave power transistors  

Microsoft Academic Search

The development of a microwave power amplifier transistor requires a highly advanced technology to achieve the basic parameters which theory predicts will be needed. In addition, very sophisticated microwave techniques must be used in the package design and characterization. Transitions between the active device and external circuitry often dominate performance. Development was started with a 7 mil2, seven-finger transistor with

H. F. Cooke; A. J. Anderson

1965-01-01

232

GaAs workshop report  

NASA Technical Reports Server (NTRS)

The advantages of GaAs over silicon are discussed. The substrate problem in solar cell fabrication was reviewed. Future trends in solar energy technology were predicted with special emphasis on cost of production.

Kamath, G. S.

1980-01-01

233

The spread of ? and Vgo and its influence on the sensitivity of a bipolar IC Celsius sensor  

Microsoft Academic Search

The parameters ? and Vgo characterize the temperature dependence of the collector current in a bipolar transistor and also the temperature sensitivity of IC Celsius sensors. There has not been complete agreement regarding the difference between experimental values obtained by several authors and the presumably considered theoretically correct values of ?=2.405 and Vgo=1.20595. In this paper new evidence will be

R Amador; A Polanco; A Nagy

1999-01-01

234

Is Cognitive Style Bipolar?  

ERIC Educational Resources Information Center

This study assessed the bipolarity of cognitive style for 970 clients of the Johnson O'Connor Research Foundation, a vocational guidance service. The 462 male and 508 female examinees were aged 14 to 65 years, with a median age of 24 years. Three cognitive style tests were investigated: (1) the Kagan Matching Familiar Figures Test (KMFFT); (2) the…

Schroeder, David H.

235

Bipolar infrapatellar tendon rupture.  

PubMed

Traumatic patella alta in children occurs either distal to the patellar tendon as a tibial tubercle apophyseal fracture or proximally as an osteochondral sleeve fracture of the inferior patellar pole. Acute surgical exploration in a pediatric case of a knee extensor mechanism rupture revealed both proximal and distal (bipolar) patellar tendon pathology. PMID:7790483

Berg, E E

1995-01-01

236

Single Photon Transistor Brad Martin  

E-print Network

Single Photon Transistor Brad Martin PH 464 #12;Brad Martin Single Photon Transistor 1 Abstract The concept of an optical transistor is not a new one. The difficulty with building optical devices that use in the nanowire. This concept can be extended to create an optical transistor device in which "current"(a flow

La Rosa, Andres H.

237

Nitrided Metallic Bipolar Plates  

SciTech Connect

The objectives are: (1) Develop and optimize stainless steel alloys amenable to formation of a protective Cr-nitride surface by gas nitridation, at a sufficiently low cost to meet DOE targets and with sufficient ductility to permit manufacture by stamping. (2) Demonstrate capability of nitridation to yield high-quality stainless steel bipolar plates from thin stamped alloy foils (no significant stamped foil warping or embrittlement). (3) Demonstrate single-cell fuel cell performance of stamped and nitrided alloy foils equivalent to that of machined graphite plates of the same flow-field design ({approx}750-1,000 h, cyclic conditions, to include quantification of metal ion contamination of the membrane electrode assembly [MEA] and contact resistance increase attributable to the bipolar plates). (4) Demonstrate potential for adoption in automotive fuel cell stacks. Thin stamped metallic bipolar plates offer the potential for (1) significantly lower cost than currently-used machined graphite bipolar plates, (2) reduced weight/volume, and (3) better performance and amenability to high volume manufacture than developmental polymer/carbon fiber and graphite composite bipolar plates. However, most metals exhibit inadequate corrosion resistance in proton exchange membrane fuel cell (PEMFC) environments. This behavior leads to high electrical resistance due to the formation of surface oxides and/or contamination of the MEA by metallic ions, both of which can significantly degrade fuel cell performance. Metal nitrides offer electrical conductivities up to an order of magnitude greater than that of graphite and are highly corrosion resistant. Unfortunately, most conventional coating methods (for metal nitrides) are too expensive for PEMFC stack commercialization or tend to leave pinhole defects, which result in accelerated local corrosion and unacceptable performance.

Brady, Michael P [ORNL; Tortorelli, Peter F [ORNL; Pihl, Josh A [ORNL; Toops, Todd J [ORNL; More, Karren Leslie [ORNL; Meyer III, Harry M [ORNL; Vitek, John Michael [ORNL; Wang, Heli [National Renewable Energy Laboratory (NREL); Turner, John [National Renewable Energy Laboratory (NREL); Wilson, Mahlon [Los Alamos National Laboratory (LANL); Garzon, Fernando [Los Alamos National Laboratory (LANL); Rockward, Tommy [Los Alamos National Laboratory (LANL); Connors, Dan [GenCell Corp; Rakowski, Jim [Allegheny Ludlum; Gervasio, Don [Arizona State University

2008-01-01

238

Long-Wavelength-Infrared Hot-Electron Transistor  

NASA Technical Reports Server (NTRS)

Dark current reduced by energy-discriminating quantum filter. Very long-wavelength-infrared hot-electron transistor developed. Device detects photons at wavelengths around 16 micrometers. Comprises photodector integrated with energy-discriminating quantum filter in multiple-quantum-well structure. Made of variously doped and undoped layers of GaAs (quantum wells) and Al(x)Ga(1-x)As (barriers between wells). In transistor, bound-to-continuum GaAs/Al(x)Ga(1-x)As multiple-quantum-well infrared photodectors (QWIP) serves as photosensitive emitter. Wide quantum well serves as base, and there is thick barrier between base and collector. Combination of barrier and base quantum well acts as energy-discriminating filter: electrons with higher energies pass through filter to collector, those with lower energies blocked and diverted from output-current path through base contact.

Gunapala, Sarath D.; Liu, John K.; Park, Jin S.; Lin, True-Lon

1995-01-01

239

IIA-2 A Novel Double Base Heterojunction Bipolar Transistor for Low Temperature Bipolar Logic  

E-print Network

.Ev. H a bias is applied betweenthe two p-SiGebaselayers,holesare injected by thermionic emissionover precludesindependentbaseoperation of the devIceat room temperature. At 77 K, however,thermionic emissionis sufficiently suppressedto at room temperature, however,the thermionic emissionacrossthe p-SiGe/i-Si/p-SiGe barrier is suppressedand

240

Metamorphic Ga0.76In0.24As/GaAs0.75Sb0.25 tunnel junctions grown on GaAs substrates  

NASA Astrophysics Data System (ADS)

Lattice-matched and pseudomorphic tunnel junctions have been developed in the past for application in a variety of semiconductor devices, including heterojunction bipolar transistors, vertical cavity surface-emitting lasers, and multijunction solar cells. However, metamorphic tunnel junctions have received little attention. In 4-junction Ga0.51In0.49P/GaAs/Ga0.76In0.24As/Ga0.47In0.53As inverted-metamorphic solar cells (4J-IMM), a metamorphic tunnel junction is required to series connect the 3rd and 4th junctions. We present a tunnel junction based on a metamorphic Ga0.76In0.24As/GaAs0.75Sb0.25 structure for this purpose. This tunnel junction is grown on a metamorphic Ga0.76In0.24As template on a GaAs substrate. The band offsets in the resulting type-II heterojunction are calculated using the first-principles density functional method to estimate the tunneling barrier height and assess the performance of this tunnel junction against other material systems and compositions. The effect of the metamorphic growth on the performance of the tunnel junctions is analyzed using a set of metamorphic templates with varied surface roughness and threading dislocation density. Although the metamorphic template does influence the tunnel junction performance, all tunnel junctions measured have a peak current density over 200 A/cm2. The tunnel junction on the best template has a peak current density over 1500 A/cm2 and a voltage drop at 15 A/cm2 (corresponding to operation at 1000 suns) lower than 10 mV, which results in a nearly lossless series connection of the 4th junction in the 4J-IMM structure.

García, I.; Geisz, J. F.; France, R. M.; Kang, J.; Wei, S.-H.; Ochoa, M.; Friedman, D. J.

2014-08-01

241

A 22 Gb\\/s decision circuit and a 32 Gb\\/s regenerating demultiplexer IC fabricated in silicon bipolar technology  

Microsoft Academic Search

A decision circuit and a 1:2 regenerating demultiplexer, which are key components in optical-fiber transmission links, were fabricated in an advanced self-aligning silicon bipolar technology using 0.8-?m lithography. Maximum speed rather than low power consumption was the main goal of these designs. The transistors were individually optimized using a semiphysical transistor model for circuit simulation. At such high operating speeds

J. HauenschildlJ; A. Felder; M. Kerber; H.-M. Rein; L. Schmidt

1992-01-01

242

Printed inorganic transistors  

E-print Network

Forty years of exponential growth of semiconductor technology have been predicated on the miniaturization of the transistors that comprise integrated circuits. While complexity has greatly increased within a given area of ...

Ridley, Brent (Brent Alan), 1974-

2003-01-01

243

The resonant gate transistor  

Microsoft Academic Search

A device is described which permits high-Qfrequency selection to be incorporated into silicon integrated circuits. It is essentially an electrostatically excited tuning fork employing field-effect transistor \\

HARVEY C. NATHANSON; WILLIAM E. NEWELL; ROBERT A. WICKSTROM

1967-01-01

244

Educating the Child with Bipolar Disorder  

MedlinePLUS

... and accommodations. How Bipolar Disorder Affects Cognition and Learning Bipolar disorder is a chronic, lifetime condition that ... tiredness, hunger, etc.) • Since bipolar disorder affects all aspects of a child’s life, it takes a well- ...

245

Update on pediatric bipolar disorder  

Microsoft Academic Search

Children and adolescents with a bipolar disorder experience mood dysregulation that is often chronic with little interepisodic\\u000a recovery. Although bipolar disorder in youth is recognized by more and more clinicians, much is still not known regarding\\u000a how best to accurately diagnose and effectively treat it. As a result, children and adolescents with bipolar disorder are\\u000a often symptomatic for long periods

Lisa D. Townsend; Christine A. Demeter; Michael Wilson; Robert L. Findling

2007-01-01

246

Fracture mechanics evaluation of GaAs  

NASA Technical Reports Server (NTRS)

A data base of mechanical and fracture properties for GaAs was generated. The data for single crystal GaAs will be used to design reusable GaAs solar modules. Database information includes; (1) physical property characterizations; (2) fracture behavior evaluations; and (3) strength of cells determined as a function of cell processing and material parameters.

Chen, C. P.

1984-01-01

247

Migraine comorbidity in bipolar disorder.  

E-print Network

??Introduction: Bipolar Disorder (BD) is a chronic mental illness associated with functional decline, mortality, and significant health care costs; furthermore, specific general medical conditions have… (more)

Ortiz-Dominguez, Tania Abigail.

2008-01-01

248

Degradation-free modulation-doped field-effect transistors grown by organometallic chemical vapor deposition  

Microsoft Academic Search

Using AlGaAs and GaAs grown by organometallic chemical vapor deposition (OMCVD), high-transconductance modulation-doped field-effect transistors which do not exhibit the severe electrical degradation in the dark at 77 K that is ordinarily observed in such devices have been fabricated. Such degradation has been attributed to defects in the n(+)-AlGaAs. Experiments on ohmic test devices using different OMCVD grown structures suggest

R. Bhat; W. K. Chan; A. Kastalsky; M. A. Koza; P. S. Davisson

1985-01-01

249

Majority carrier type conversion in solution-processed organic transistors and flexible complementary logic circuits  

NASA Astrophysics Data System (ADS)

We report on the realization of high performance solution-processed ambipolar organic transistors based on a quinoidal oligothiophene derivative. The devices show hole and electron field-effect mobilities in air as high as 0.1 and 0.006 cm2 V-1 s-1, respectively, and can be converted from ambipolar p-type dominant to n-type transistors by thermal annealing. The conversion of the majority carrier type is assigned to strong variations in molecular packing. The demonstration of complementary flexible inverters suggests an effective strategy for patterning lateral pn-bipolar structures in solution-processed thin films made from a monolithic ambipolar organic semiconductor.

Ribierre, J. C.; Watanabe, S.; Matsumoto, M.; Muto, T.; Aoyama, T.

2010-02-01

250

A Six Transistors Full Adder  

Microsoft Academic Search

A new six transistors multiple-valued current mode one bit full adder is presented. Simulations results utilizing standard 0.18 µm CMOS technology illustrate a significant improvement in terms of number of transistors, chip area and propagation delay.

K. Navi; V. Foroutan; B. Mazloomnejad; O. Hashemipour; M. Haghparast

2008-01-01

251

Impact of 110 uniaxial strain on n-channel In0.15Ga0.85As high electron mobility transistors  

E-print Network

This letter reports on a study of the impact of ?110? uniaxial strain on the characteristics of InGaAs high electron mobility transistors (HEMT) by bending GaAs chips up to a strain level of 0.4%. Systematic changes in the ...

Xia, Ling

252

Impact of ?110? uniaxial strain on n-channel In0.15Ga0.85As high electron mobility transistors  

E-print Network

This letter reports on a study of the impact of ?110? uniaxial strain on the characteristics of InGaAs high electron mobility transistors (HEMT) by bending GaAs chips up to a strain level of 0.4%. Systematic changes in ...

del Alamo, Jesus A.

253

Growth and properties of crystalline barium oxide on the GaAs(100) substrate  

NASA Astrophysics Data System (ADS)

Growing a crystalline oxide film on III-V semiconductor renders possible approaches to improve operation of electronics and optoelectronics heterostructures such as oxide/semiconductor junctions for transistors and window layers for solar cells. We demonstrate the growth of crystalline barium oxide (BaO) on GaAs(100) at low temperatures, even down to room temperature. Photoluminescence (PL) measurements reveal that the amount of interface defects is reduced for BaO/GaAs, compared to Al2O3/GaAs, suggesting that BaO is a useful buffer layer to passivate the surface of the III-V device material. PL and photoemission data show that the produced junction tolerates the post heating around 600 °C.

Yasir, M.; Dahl, J.; Kuzmin, M.; Lâng, J.; Tuominen, M.; Punkkinen, M. P. J.; Laukkanen, P.; Kokko, K.; Korpijärvi, V.-M.; Polojärvi, V.; Guina, M.

2013-11-01

254

Bipolar pulse forming line  

DOEpatents

A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

Rhodes, Mark A. (Pleasanton, CA)

2008-10-21

255

Bipolar Disorder Among Children Overall Prevalence  

E-print Network

Bipolar Disorder Among Children Overall Prevalence � Bipolar Disorder usually starts in late adolescence or early adulthood, but children can have bipolar disorder too. � Community studies estimate lifetime prevalence of bipolar spectrum disorders to be 0% to 3% among adolescents, depending

Baker, Chris I.

256

The Stanley Foundation Bipolar Treatment Outcome Network  

Microsoft Academic Search

Background: Since recent NIMH Bipolar Disorder Workshops highlighted the dearth of longitudinal and controlled studies of bipolar illness, the Stanley Foundation Bipolar Network (SFBN) has recruited a large cohort of patients with bipolar disorder to begin to address these issues. This report describes the demographics and course of illness characteristics of this study population. Methods: The first 261 outpatients to

Trisha Suppes; Gabriele S Leverich; Paul E Keck; Willem A Nolen; Kirk D Denicoff; Lori L Altshuler; Susan L McElroy; A. John Rush; Ralph Kupka; Mark A Frye; Maia Bickel; Robert M Post

2001-01-01

257

Polariton Condensate Transistor Switch  

E-print Network

A polariton condensate transistor switch is realized through optical excitation of a microcavity ridge with two beams. The ballistically ejected polaritons from a condensate formed at the source are gated using the 20 times weaker second beam to switch on and off the flux of polaritons. In the absence of the gate beam the small built-in detuning creates potential landscape in which ejected polaritons are channelled toward the end of the ridge where they condense. The low loss photon-like propagation combined with strong nonlinearities associated with their excitonic component makes polariton based transistors particularly attractive for the implementation of all-optical integrated circuits.

Gao, T; Liew, T C H; Tsintzos, S I; Stavrinidis, G; Deligeorgis, G; Hatzopoulos, Z; Savvidis, P G

2012-01-01

258

Single electron transistor in pure silicon  

NASA Astrophysics Data System (ADS)

As promising candidates for spin qubits, semiconductor quantum dots (QDs) have attracted tremendous research efforts. Currently most advanced progress is from GaAs QDs. Compared to GaAs, lateral QDs in 28silicon are expected to have a spin coherence time orders of magnitude longer, because 28Si has zero nuclear spin, and there is no hyperfine interaction between electron spins and nuclear spins. We have developed enhancement mode metal-oxide-semiconductor (MOS) single electron transistors (SETs) using pure silicon wafers with a bi-layer gated configuration. In an MOS-SET, the top gate is used to induce a two-dimensional electron gas (2DEG), just as in an MOS field effect transistor. The side gates deplete the 2DEG into a QD and two point contact channels; one connects the QD to the source reservoir, and the other connects the QD to the drain reservoir. We have systematically investigated the MOS-SETs at 4.2 K, and separately in a dilution refrigerator with a base temperature of 10 mK. The data show that there is an intrinsic QD in each point contact channel due to the local potential fluctuations in these SETs. However, after scaling down the SETs, we have found that the intrinsic QDs can be removed and the electrostatically defined dots dominate the device behavior, but these devices currently only work in the many-electron regime. In order to realize single electron confinement, it is necessary to continue scaling down the device and improving the interface quality. To explore the spin dynamics in silicon, we have investigated a single intrinsic QD by applying a magnetic field perpendicular to the sample surface. The magnetic field dependence of the ground-state and excited-state energy levels of the QD mostly can be explained by the Zeeman effect, with no obvious orbital effect up to 9 T. The two-electron singlet-triplet (ST) transition is first time directly observed in a silicon QD by excitation spectroscopy. In this ST transition, electron-electron Coulomb interaction plays a significant role. The observed amplitude spectrum suggests the spin blockade effect. When the two-electron system forms a singlet state in the dot at low fields, and the injection current from the lead becomes spin-down polarized, the tunneling conductance is reduced by a factor of 8. At higher magnetic fields, due to the ST transition, the spin blockade effect is lifted and the conductance is fully recovered.

Hu, Binhui

259

Multimode silicon nanowire transistors.  

PubMed

The combined capabilities of both a nonplanar design and nonconventional carrier injection mechanisms are subject to recent scientific investigations to overcome the limitations of silicon metal oxide semiconductor field effect transistors. In this Letter, we present a multimode field effect transistors device using silicon nanowires that feature an axial n-type/intrinsic doping junction. A heterostructural device design is achieved by employing a self-aligned nickel-silicide source contact. The polymorph operation of the dual-gate device enabling the configuration of one p- and two n-type transistor modes is demonstrated. Not only the type but also the carrier injection mode can be altered by appropriate biasing of the two gate terminals or by inverting the drain bias. With a combined band-to-band and Schottky tunneling mechanism, in p-type mode a subthreshold swing as low as 143 mV/dec and an ON/OFF ratio of up to 10(4) is found. As the device operates in forward bias, a nonconventional tunneling transistor is realized, enabling an effective suppression of ambipolarity. Depending on the drain bias, two different n-type modes are distinguishable. The carrier injection is dominated by thermionic emission in forward bias with a maximum ON/OFF ratio of up to 10(7) whereas in reverse bias a Schottky tunneling mechanism dominates the carrier transport. PMID:25303290

Glassner, Sebastian; Zeiner, Clemens; Periwal, Priyanka; Baron, Thierry; Bertagnolli, Emmerich; Lugstein, Alois

2014-11-12

260

A Matterwave Transistor Oscillator  

E-print Network

An atomtronic transistor circuit is used to realize a driven matterwave oscillator. The transistor consists of Source and Drain regions separated by a narrow Gate well. Quasi-steady-state behavior is determined from a thermodynamic model, which reveals two oscillation threshold regimes. One is due to the onset of Bose-Einstein condensation in the Gate well, the other is due to the appearance of a negative transresistance regime of the transistor. The thresholds of oscillation are shown to be primarily dependent on the potential energy height difference between Gate-Drain and Gate-Source barriers. The transistor potential is established with a combination of magnetic and optical fields using a compound glass and silicon substrate atom chip. The onset of oscillation and the output matterwave are observed through in-trap imaging. Time-of-flight absorption imaging is used to determine the time dependence of the Source well thermal and chemical energies as well as to estimate the value of the closed-loop ohmic Gate resistance, which is negative and is observed to cause cooling of Source atoms.

Seth C. Caliga; Cameron J. E. Straatsma; Alex A. Zozulya; Dana Z. Anderson

2012-08-15

261

A Matterwave Transistor Oscillator  

E-print Network

A triple-well atomtronic transistor combined with forced RF evaporation is used to realize a driven matterwave oscillator circuit. The transistor is implemented using a metalized compound glass and silicon substrate. On-chip and external currents produce a cigar-shaped magnetic trap, which is divided into transistor source, gate, and drain regions by a pair of blue-detuned optical barriers projected onto the magnetic trap through a chip window. A resonant laser beam illuminating the drain portion of the atomtronic transistor couples atoms emitted by the gate to the vacuum. The circuit operates by loading the source with cold atoms and utilizing forced evaporation as a power supply that produces a positive chemical potential in the source, which subsequently drives oscillation. High-resolution in-trap absorption imagery reveals gate atoms that have tunneled from the source and establishes that the circuit emits a nominally mono-energetic matterwave with a frequency of 23.5(1.0) kHz by tunneling from the gate, ...

Caliga, Seth C; Zozulya, Alex A; Anderson, Dana Z

2012-01-01

262

Indirect bipolar electrodeposition.  

PubMed

Based on the principles of bipolar electrochemistry, localized pH gradients are generated at the surface of conducting particles in solution. This allows the toposelective deposition of inorganic and organic polymer layers via a pH-triggered precipitation mechanism. Due to the intrinsic symmetry breaking of the process, the concept can be used to generate in a straightforward way Janus particles, with one section consisting of deposits obtained from non-electroactive precursors. These indirect electrodeposits, such as SiO(2), TiO(2), or electrophoretic paints, can be further used as an immobilization matrix for other species like dyes or nanoparticles, thus opening promising perspectives for the synthesis of a variety of bifunctional objects with a controlled shape. PMID:23186018

Loget, Gabriel; Roche, Jérome; Gianessi, Eugenio; Bouffier, Laurent; Kuhn, Alexander

2012-12-12

263

Genetics of bipolar disorder  

PubMed Central

Bipolar disorder is a common, complex genetic disorder, but the mode of transmission remains to be discovered. Many researchers assume that common genomic variants carry some risk for manifesting the disease. The research community has celebrated the first genome-wide significant associations between common single nucleotide polymorphisms (SNPs) and bipolar disorder. Currently, attempts are under way to translate these findings into clinical practice, genetic counseling, and predictive testing. However, some experts remain cautious. After all, common variants explain only a very small percentage of the genetic risk, and functional consequences of the discovered SNPs are inconclusive. Furthermore, the associated SNPs are not disease specific, and the majority of individuals with a “risk” allele are healthy. On the other hand, population-based genome-wide studies in psychiatric disorders have rediscovered rare structural variants and mutations in genes, which were previously known to cause genetic syndromes and monogenic Mendelian disorders. In many Mendelian syndromes, psychiatric symptoms are prevalent. Although these conditions do not fit the classic description of any specific psychiatric disorder, they often show nonspecific psychiatric symptoms that cross diagnostic boundaries, including intellectual disability, behavioral abnormalities, mood disorders, anxiety disorders, attention deficit, impulse control deficit, and psychosis. Although testing for chromosomal disorders and monogenic Mendelian disorders is well established, testing for common variants is still controversial. The standard concept of genetic testing includes at least three broad criteria that need to be fulfilled before new genetic tests should be introduced: analytical validity, clinical validity, and clinical utility. These criteria are currently not fulfilled for common genomic variants in psychiatric disorders. Further work is clearly needed before genetic testing for common variants in psychiatric disorders should be established. PMID:24683306

Kerner, Berit

2014-01-01

264

Dual-Side Wafer Processing and Resonant Tunneling Transistor Applications  

SciTech Connect

We describe dual-side wafer processing and its application to resonant tunneling transistors in a planar configuration. The fabrication technique utilizes a novel flip-chip, wafer thinning process called epoxy-bond and stop-etch (EBASE) process, where the substrate material is removed by selective wet etching and stopped at an etch-stop layer. This EBASE method results in a semiconductor epitaxial layer that is typically less than a micron thick and has a mirror-finish, allowing backside gates to be placed in close proximity to frontside gates. Utilizing this technique, a resonant tunneling transistor--the double electron layer tunneling transistor (DELTT)--can be fabricated in a fully planar configuration, where the tunneling between two selectively-contacted 2DEGs in GaAs or InGaAs quantum wells is modulated by surface Schottky gate. Low temperature electrical characterization yields source-drain I-V curves with a gate-tunable negative differential resistance.

Moon, J.S.; Simmons, J.A.; Wendt, J.R.; Hietala, V.M.; Reno, J.L.; Baca, W.E.; Blount, M.A.

1999-07-20

265

Managing Pregnancy and Bipolar Disorder  

MedlinePLUS

... Some details concerning specific medications are listed below. Lithium For many people, lithium is a mainstay of their treatment for bipolar disorder. The decision to continue taking lithium during pregnancy can be life saving to the ...

266

A high-speed bipolar technology featuring self-aligned single-poly base and submicrometer emitter contacts  

Microsoft Academic Search

An experimental bipolar transistor structure with self-aligned base-emitter contacts formed using one polysilicon layer is presented with geometries and frequency performance comparable to those of double-polysilicon structures. This structure, called STRIPE (self-aligned trench-isolated polysilicon electrodes), provides a 0.2-?m emitter-base polysilicon contact separation. A 0.4-?m emitter width is achieved with conventional 0.8-?m optical lithography. Scaling of the emitter width of 0.3

W. M. Huang; C. I. Drowley; P. J. Vande Voorde; D. Pettengill; J. E. Turner; A. K. Kapoor; C.-H. Lin; G. Burton; S. J. Rosner; K. Brigham; H.-S. Fu; S.-Y. Oh; M. P. Scott; S.-Y. Chiang; A. Wang

1990-01-01

267

The microtubule transistor  

E-print Network

I point out the similarity between the microtubule experiment reported by Priel et al [Biophys. J. 90, 4639 (2006)] and the ZnO nanowire experiment of Wang et al [Nanolett. 6, 2768 (2006)]. It is quite possible that MTs are similar to a piezoelectric field effect transistor for which the role of the control gate electrode is played by the piezo-induced electric field across the width of the MT walls and their elastic bending features

H. C. Rosu

2007-03-26

268

Gate-all-around polycrystalline-silicon thin-film transistors with self-aligned grain-growth nanowire channels  

NASA Astrophysics Data System (ADS)

In this letter, gate-all-around (GAA) polycrystalline silicon thin-film transistors (TFTs) with self-aligned grain-growth channels were fabricated using excimer laser crystallization (ELC) on a recessed-nanowire (RN) structure. Via the RN structure constructed by a simple sidewall-spacer formation, location-controlled nucleation and volume-confined lateral grain growth within the RN body during ELC process have been demonstrated with only one perpendicular grain boundary in each nanowire channel. Because of the high-crystallinity channel together with GAA operation mode, the proposed GAA-RN TFTs show good device integrity of lower threshold voltage, steeper subthreshold slope, and higher field-effect mobility as compared with the conventional planar counterparts.

Liao, Ta-Chuan; Kang, Tsung-Kuei; Lin, Chia-Min; Wu, Chun-Yu; Cheng, Huang-Chung

2012-02-01

269

Creativity in familial bipolar disorder.  

PubMed

Studies have demonstrated relationships between creativity and bipolar disorder (BD) in individuals, and suggested familial transmission of both creativity and BD. However, to date, there have been no studies specifically examining creativity in offspring of bipolar parents and clarifying mechanisms of intergenerational transmission of creativity. We compared creativity in bipolar parents and their offspring with BD and bipolar offspring with attention-deficit/hyperactivity disorder (ADHD) with healthy control adults and their children. 40 adults with BD, 20 bipolar offspring with BD, 20 bipolar offspring with ADHD, and 18 healthy control parents and their healthy control children completed the Barron-Welsh Art Scale (BWAS), an objective measure of creativity. Adults with BD compared to controls scored significantly (120%) higher on the BWAS Dislike subscale, and non-significantly (32%) higher on the BWAS Total scale. Mean BWAS Dislike subscale scores were also significantly higher in offspring with BD (107% higher) and offspring with ADHD (91% higher) than in healthy control children. Compared to healthy control children, offspring with BD had 67% higher and offspring with ADHD had 40% higher BWAS Total scores, but these differences failed to reach statistical significance when adjusted for age. In the bipolar offspring with BD, BWAS Total scores were negatively correlated with duration of illness. The results of this study support an association between BD and creativity and contribute to a better understanding of possible mechanisms of transmission of creativity in families with genetic susceptibility for BD. This is the first study to show that children with and at high risk for BD have higher creativity than healthy control children. The finding in children and in adults was related to an enhanced ability to experience and express dislike of simple and symmetric images. This could reflect increased access to negative affect, which could yield both benefits with respect to providing affective energy for creative achievement, but also yield liabilities with respect to quality of interpersonal relationships or susceptibility to depression. PMID:16157163

Simeonova, Diana I; Chang, Kiki D; Strong, Connie; Ketter, Terence A

2005-11-01

270

The Genetics of Bipolar Disorder  

PubMed Central

Bipolar disorder is a mood disorder characterized by impairing episodes of mania and depression. Twin studies have established that bipolar disorder is among the most heritable of medical disorders and efforts to identify specific susceptibility genes have intensified over the past two decades. The search for genes influencing bipolar disorder has been complicated by a paucity of animal models, limited understanding of pathogenesis, and the genetic and phenotypic complexity of the syndrome. Linkage studies have implicated several chromosomal regions as harboring relevant genes, but results have been inconsistent. It is now widely accepted that the genetic liability to bipolar disorder reflects the action of many genes of individually small effect, a scenario for which linkage studies are poorly suited. Thus, association studies, which are more powerful for the detection of modest effect loci, have become the focus of gene-finding research. A large number of candidate genes, including biological candidates derived from hypotheses about the pathogenesis of the disorder and positional candidates derived from linkage and cytogenetic studies, have been evaluated. Several of these genes have been associated with the disorder in independent studies (including BDNF, DAOA, DISC1, GRIK4, SLC6A4, and TPH2), but none has been established. The clinical heterogeneity of bipolar disorder and its phenotypic and genetic overlap with other disorders (especially schizophrenia, schizoaffective disorder, and major depressive disorder) has raised questions about the optimal phenotype definition for genetic studies. Nevertheless, genomewide association analysis, which has successfully identified susceptibility genes for a variety of complex disorders, has begun to implicate specific genes for bipolar disorder (DGKH, CACNA1C, ANK3). The polygenicity of the disorder means that very large samples will be needed to detect the modest effect loci that likely contribute to bipolar disorder. Detailed genetic dissection of the disorder may provide novel targets (both pharmacologic and psychosocial) for intervention. PMID:19358880

Barnett, Jennifer H; Smoller, Jordan W

2009-01-01

271

Integrated neurobiology of bipolar disorder.  

PubMed

From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity - reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition - limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional "unified field theory" of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial-neuronal interactions. Among these glial elements are microglia - the brain's primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the hypothalamic-pituitary-adrenal axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway, or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of bipolarity is one of the great questions facing the field and one that is likely to have profound treatment implications, given that fact that such a discovery would greatly increase our ability to individualize - and by extension, enhance - treatment. PMID:25202283

Maletic, Vladimir; Raison, Charles

2014-01-01

272

Integrated Neurobiology of Bipolar Disorder  

PubMed Central

From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity – reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition – limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional “unified field theory” of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial–neuronal interactions. Among these glial elements are microglia – the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the hypothalamic–pituitary–adrenal axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway, or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of bipolarity is one of the great questions facing the field and one that is likely to have profound treatment implications, given that fact that such a discovery would greatly increase our ability to individualize – and by extension, enhance – treatment.

Maletic, Vladimir; Raison, Charles

2014-01-01

273

Bipolar (Spectrum) Disorder and Mood Stabilization: Standing at the Crossroads?  

Microsoft Academic Search

Diagnosis and treatment of bipolar disorder has long been a neglected discipline. Recent years have shown an upsurge in bipolar research. When compared to major depressive disorder, bipolar research still remains limited and more expert based than evidence based. In bipolar diagnosis the focus is shifting from classic mania to bipolar depression and hypomania. There is a search for bipolar

Jürgen De Fruyt; Koen Demyttenaere

2007-01-01

274

Early onset bipolar disorder Early Onset Bipolar Disorder: validation from admixture analyses and biomarkers.  

E-print Network

Early onset bipolar disorder 1 Early Onset Bipolar Disorder: validation from admixture analyses of Psychiatry / Revue Canadienene de Psychiatrie 2013;58(4):240-248" #12;Early onset bipolar disorder 2 Abstract: Objectives: Bipolar affective disorder (BD) is a multifactorial disorder with heterogeneous clinical

Paris-Sud XI, Université de

275

Bipolar patients with seasonal pattern 1 BIPOLAR DISORDER WITH SEASONAL PATTERN  

E-print Network

Bipolar patients with seasonal pattern 1 BIPOLAR DISORDER WITH SEASONAL PATTERN: CLINICAL. Referees proposed for the review of the manuscript: 1) JM Goikolea, jm.goikolea@clinic.ub.es Bipolar, published in "Chronobiology International 2013;30(9):1101-7" DOI : 10.3109/07420528.2013.800091 #12;Bipolar

Boyer, Edmond

276

Brainstorm: occupational choice, bipolar illness and creativity.  

PubMed

Although economists have analyzed earnings, unemployment, and labor force participation for those with bipolar illness, occupational choice has yet to be explored. Psychological and medical studies often suggest an association between bipolar illness and creative achievement, but they tend to focus on eminent figures, case studies, or small samples. We seek to examine occupational creativity of non-eminent individuals with bipolar disorder. We use Epidemiologic Catchment Area data to estimate a multinomial logit model matched to an index of occupational creativity. Those with bipolar illness appear to be disproportionately concentrated in the most creative occupational category. Nonparametric kernel density estimates reveal that the densities of the occupational creativity variable for the bipolar and non-bipolar individuals significantly differ in the ECA data, and suggest that the probability of engaging in creative activities on the job is higher for bipolar than non-bipolar workers. PMID:20138016

Tremblay, Carol Horton; Grosskopf, Shawna; Yang, Ke

2010-07-01

277

Identification and management of bipolar disorder.  

PubMed

Bipolar disorder is a complex and chronic mental illness. Individuals with this disorder usually have medical comorbidities needing management in primary care. This article focuses on bipolar disorder identification and medication management concerns for primary care nurse practitioners. PMID:25208039

Scrandis, Debra A

2014-10-15

278

Bipolar disorder in youth: An update  

Microsoft Academic Search

The authors highlight some of the important findings regarding juvenile-onset bipolar disorder that have been published in\\u000a recent years. Topics covered include the impact of definition on understanding epidemiologic studies of early-onset bipolar\\u000a disorder, comorbidity, developmental risk factors, switching and medication response, family studies, and treatment. Some\\u000a of the controversy surrounding bipolar disorder in youth diminishes if bipolar disorder is

Stephanie E. Meyer; Gabrielle A. Carlson

2003-01-01

279

Creativity in familial bipolar disorder q  

Microsoft Academic Search

Studies have demonstrated relationships between creativity and bipolar disorder (BD) in individuals, and suggested familial transmission of both creativity and BD. However, to date, there have been no studies specifically examining creativity in o!spring of bipolar parents and clarifying mechanisms of intergenerational transmission of creativity. We compared creativity in bipolar par- ents and their o!spring with BD and bipolar o!spring

Diana I. Simeonova; Kiki D. Chang; Connie Strong; Terence A. Ketter

2005-01-01

280

Brainstorm: Occupational choice, bipolar illness and creativity  

Microsoft Academic Search

Although economists have analyzed earnings, unemployment, and labor force participation for those with bipolar illness, occupational choice has yet to be explored. Psychological and medical studies often suggest an association between bipolar illness and creative achievement, but they tend to focus on eminent figures, case studies, or small samples. We seek to examine occupational creativity of non-eminent individuals with bipolar

Carol Horton Tremblay; Shawna Grosskopf; Ke Yang

2010-01-01

281

Neurobiological basis of bipolar disorder Tadafumi Kato  

E-print Network

Neurobiological basis of bipolar disorder Tadafumi Kato Laboratory for Molecular Dynamics of Mental Disorders, RIKEN Brain Science Institute Bipolar disorder is characterized by recurrent episodes of mania channel genes including CACNA1C. Mendelian diseases accompanying bipolar disorder or depression include

Fukai, Tomoki

282

Social Desirability And Bipolar Affective Disorder  

ERIC Educational Resources Information Center

Exploring the bipolar (manic-depressive) and the unipolar (depression without mania) subtypes of primary affective disorders, this study determines whether the conforming attitudes of bipolar subjects are related to depression as possible coping mechanisms. The findings explain the less self-reported depression and psychopathology in the bipolar

Donnelly, Howard F.; Murphy, Dennis L.

1973-01-01

283

Psychotherapy of bipolar disorder: a review  

Microsoft Academic Search

Background: Bipolar disorder is often only partially treated by medication alone, which has led to recent developments in the adjunctive psychological treatment of bipolar disorder. This paper aims to examine the current evidence for effectiveness of psychological interventions for bipolar disorder and to identify issues for future research in this area. Method: A review of outcome studies of psychological interventions

Steven Jones

2004-01-01

284

Use of psychoeducation in the treatment of bipolar disorder in the treatment of bipolar disorder in the treatment of bipolar disorder in the treatment of bipolar disorder  

Microsoft Academic Search

Bipolar disorder shows significant chronicity and severity of symptoms usually causing psychosocial damage. Pharmacological treatment is considered essential for bipolar patients. However, in the psychosocial field, an association between stressors and precipitation of bipolar episodes has been clearly documented, highlighting the need for intervention in this field. As for psychoeducation, this consists of a psychosocial intervention model. The present study

Ângela Leggerini de Figueiredo

285

Psychotic symptoms in pediatric bipolar disorder  

Microsoft Academic Search

Background: There is under-recognition or misdiagnosis of pediatric bipolar disorder with psychotic features. It is of major public health importance to recognize psychosis in bipolar disorder. Method: Original research on phenomenological description of psychosis and external validators including family history, longitudinal course and treatment effects are systematically reviewed. Age differences, sampling, and interview methods of the studies on pediatric bipolar

Mani N. Pavuluri; Ellen S. Herbener; John A. Sweeney

2004-01-01

286

Functional Remediation for Bipolar Disorder  

PubMed Central

Neurocognitive impairment constitutes a core feature of bipolar illness. The main domains affected are verbal memory, attention, and executive functions. Deficits in these areas as well as difficulties to get functional remission seem to be increased associated with illness progression. Several studies have found a strong relationship between neurocognitive impairment and low functioning in bipolar disorder, as previously reported in other illnesses such as schizophrenia. Cognitive remediation strategies, adapted from work conducted with traumatic brain injury patients and applied to patients with schizophrenia, also need to be adapted to individuals with bipolar disorders. Early intervention using functional remediation, involves neurocognitive techniques and training, but also psychoeducation on cognition-related issues and problem-solving within an ecological framework. PMID:21687565

Martinez-Aran, Anabel; Torrent, Carla; Sole, Brisa; Bonnin, C. Mar; Rosa, Adriane R; Sanchez-Moreno, Jose; Vieta, Eduard

2011-01-01

287

Mathematical Models of Bipolar Disorder  

E-print Network

We use limit cycle oscillators to model Bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about one percent of the United States adult population. We consider two nonlinear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individuals using weakly-coupled, weakly-damped harmonic oscillators. We discuss how the proposed models can be used as a framework for refined models that incorporate additional biological data. We conclude with a discussion of possible generalizations of our work, as there are several biologically-motivated extensions that can be readily incorporated into the series of models presented here.

Darryl Daugherty; Tairi Roque-Urrea; John Urrea-Roque; Jessica Snyder; Stephen Wirkus; Mason A. Porter

2003-11-17

288

Bipolar lead acid battery development  

NASA Technical Reports Server (NTRS)

A modular bipolar battery configuration is under development at Johnson Control, Inc. (JCI) and the Jet Propulsion Laboratory (JPL). The battery design, incorporating proven lead acid electrochemistry, yields a rechargeable, high-power source that is light weight and compact. This configuration offers advantages in power capability, weight, and volume over conventional monopolar batteries and other battery chemistries. The lead acid bipolar battery operates in a sealed, maintenance-free mode allowing for maximum application flexibility. It is ideal for high-voltage and high-power applications.

Eskra, Michael; Vidas, Robin; Miles, Ronald; Halpert, Gerald; Attia, Alan; Perrone, David

1991-01-01

289

RICE UNIVERSITY Transport in Single Molecule Transistors  

E-print Network

RICE UNIVERSITY Transport in Single Molecule Transistors by Lam H. Yu A Thesis Submitted in Partial Houston, Texas January, 2006 #12;Abstract Transport in Single Molecule Transistors by Lam H. Yu molecule transistors (SMTs), nanometer-scale transistors in which charge transport occurs through

Natelson, Douglas

290

High efficiency GaAs solar cells  

NASA Technical Reports Server (NTRS)

The present status of the GaAlAs/GaAs heteroface solar cell program is reported. Studies have been concentrated on GaAlAs/GaAs heteroface solar cells; however, some research has been conducted on thin junction, diffused GaAs solar cells. Emphasis has been on obtaining high efficiency (18% to 20%) GaAs solar cells. Two problems that have limited the efficiency of GaAs solar cells are the high recombination velocity of carriers near the surface and the low minority carrier diffusion length in n-GaAs.

Walker, G. H.; Conway, E. J.; Byvik, C. E.

1977-01-01

291

Vertical gate-all-around junctionless nanowire transistors with asymmetric diameters and underlap lengths  

NASA Astrophysics Data System (ADS)

Vertical gate-all-around (GAA) junctionless nanowire transistors (JNTs) with different diameters and underlap lengths are investigated using three-dimensional device simulations. The source-side diameter determines the on-current and drain-induced barrier lowering characteristics, whereas the drain-side diameter controls the band-to-band tunneling current during off-state conditions. The JNTs with short drain-side underlap lengths decrease the source/drain series resistance but increase the off-current values, especially due to large band-gap narrowing effects at the drain extension region. Proper device design of vertical GAA JNTs considering the device structure and underlap is needed to improve both on/off and short channel characteristics.

Yoon, Jun-Sik; Rim, Taiuk; Kim, Jungsik; Meyyappan, Meyya; Baek, Chang-Ki; Jeong, Yoon-Ha

2014-09-01

292

High-frequency operation of 0.3 {mu}m GaAs JFETs for low-power electronic  

SciTech Connect

GaAs Junction Field Effect Transistors (JFETs) have attracted renewed attention for low-power, low-voltage electronics. JFETs have a significant advantage over MESFETs for low-power operation due to their higher gate barrier to current flow resulting from p/n junction gate. This paper reports recent advances in an all ion implanted self-aligned GaAs JFET with a gate length down to 0.3 {mu}m. By employing shallopw SiF implants next to the gate, dielectric sidewall spacers, and 50 keV source and drain implants, JFETs with a f{sub t} up to 49 GHz with good pinchoff and subthreshold characteristics have been realized. In addition, the JFET benefits from the use of shallow Zn or Cd implantation to form abrupt p{sup +}/n gate profiles.

Zolper, J.C.; Baca, A.G.; Hietala, V.M.; Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); Sherwin, M.E. [Microwave Signal, Clarksburg, MD (United States)

1996-09-01

293

Corrosion resistant metallic bipolar plate  

DOEpatents

A corrosion resistant, electrically conductive component such as a bipolar plate for a PEM fuel cell includes 20 55% Cr, balance base metal such as Ni, Fe, or Co, the component having thereon a substantially external, continuous layer of chromium nitride.

Brady, Michael P. (Oak Ridge, TN); Schneibel, Joachim H. (Knoxville, TN); Pint, Bruce A. (Knoxville, TN); Maziasz, Philip J. (Oak Ridge, TN)

2007-05-01

294

An analytic model for gate-all-around silicon nanowire tunneling field effect transistors  

NASA Astrophysics Data System (ADS)

An analytical model of gate-all-around (GAA) silicon nanowire tunneling field effect transistors (NW-TFETs) is developted based on the surface potential solutions in the channel direction and considering the band to band tunneling (BTBT) efficiency. The three-dimensional Poisson equation is solved to obtain the surface potential distributions in the partition regions along the channel direction for the NW-TFET, and a tunneling current model using Kane's expression is developed. The validity of the developed model is shown by the good agreement between the model predictions and the TCAD simulation results.

Liu, Ying; He, Jin; Chan, Mansun; Du, Cai-Xia; Ye, Yun; Zhao, Wei; Wu, Wen; Deng, Wan-Ling; Wang, Wen-Ping

2014-09-01

295

Pulse transformer for GaAs laser  

NASA Technical Reports Server (NTRS)

High-radiance gallium arsenide (GaAs) laser operating at room temperature is utilized in optical navigation system. For efficient transformer-to-laser impedance match, laser should be connected directly to pulse transformer secondary winding.

Rutz, E. M.

1976-01-01

296

Ion-implanted GaAs JFETs with f{sub t} {gt} 45 GHz for low-power electronics  

SciTech Connect

GaAs Junction Field Effect Transistors (JFETs) are reported with gate lengths down to 0.3 micrometers. The structure is fully self-aligned and employs all ion implantation doping. p[sup +]-gate regions are formed with either Zn or Cd implants along with a P coimplantation to reduce diffusion. The source and rain implants are engineered with Si or SiF implants to minimize short channel effects. JFETs with 0.3 micrometer gate length are demonstrated with a sub-threshold slope of 110 mV/decade along with an intrinsic unity current gain cutoff frequency as high as 52 GHz.

Zolper, J.C.; Baca, A.G.; Hietala, V.M.; Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); Sherwin, M.E. [Sandia National Labs., Albuquerque, NM (United States)]|[Microwave Signal, Clarksburg, MD (United States)

1996-12-31

297

GaAs homojunction solar cell development  

NASA Technical Reports Server (NTRS)

The Lincoln Laboratory n(+)/p/p(+) GaAs shallow homojunction cell structure was successfully demonstrated on 2 by 2 cm GaAs substrates. Air mass zero efficiencies of the seven cells produced to date range from 13.6 to 15.6 percent. Current voltage (I-V) characteristics, spectral response, and measurements were made on all seven cells. Preliminary analysis of 1 MeV electron radiation damage data indicate excellent radiation resistance for these cells.

Flood, D. J.; Swartz, C. K.; Hart, R. E., Jr.

1980-01-01

298

Cryogenic transistor measurement and modeling for engineering applications  

NASA Astrophysics Data System (ADS)

This article deals with the methodology of an electronic system design at liquid-helium temperatures. This technique includes the active device selection, characterization and simulation. Based on certain engineering criteria one commercial reference of SiGe heterojunction bipolar transistors is selected. Then, the technique of device characterization and measurement is considered. Typical output characteristics are given for this reference. All the tested devices of this reference are classified into three groups according to the presence of different low-temperature phenomena. An accurate and easy-to-use neural network model based on their experimental DC characteristics is proposed. This model is implemented in Agilent ADS Software, and the simulation results are compared with measurements in the course of the cryogenic amplifier design.

Goryachev, Maxim; Galliou, Serge; Abbé, Philippe

2010-06-01

299

Adiabatic Quantum Transistors  

E-print Network

We describe a many-body quantum system which can be made to quantum compute by the adiabatic application of a large applied field to the system. Prior to the application of the field quantum information is localized on one boundary of the device, and after the application of the field this information has propagated to the other side of the device with a quantum circuit applied to the information. The applied circuit depends on the many-body Hamiltonian of the material, and the computation takes place in a degenerate ground space with symmetry-protected topological order. Such adiabatic quantum transistors are universal adiabatic quantum computing devices which have the added benefit of being modular. Here we describe this model, provide arguments for why it is an efficient model of quantum computing, and examine these many-body systems in the presence of a noisy environment.

Dave Bacon; Steven T. Flammia; Gregory M. Crosswhite

2012-07-11

300

Adiabatic Quantum Transistors  

We describe a many-body quantum system that can be made to quantum compute by the adiabatic application of a large applied field to the system. Prior to the application of the field, quantum information is localized on one boundary of the device, and after the application of the field, this information propagates to the other side of the device, with a quantum circuit applied to the information. The applied circuit depends on the many-body Hamiltonian of the material, and the computation takes place in a degenerate ground space with symmetry-protected topological order. Such “adiabatic quantum transistors” are universal adiabatic quantum computing devices that have the added benefit of being modular. Here, we describe this model, provide arguments for why it is an efficient model of quantum computing, and examine these many-body systems in the presence of a noisy environment.

Bacon, Dave; Flammia, Steven T.; Crosswhite, Gregory M.

2013-06-01

301

High transconductance organic electrochemical transistors  

PubMed Central

The development of transistors with high gain is essential for applications ranging from switching elements and drivers to transducers for chemical and biological sensing. Organic transistors have become well-established based on their distinct advantages, including ease of fabrication, synthetic freedom for chemical functionalization, and the ability to take on unique form factors. These devices, however, are largely viewed as belonging to the low-end of the performance spectrum. Here we present organic electrochemical transistors with a transconductance in the mS range, outperforming transistors from both traditional and emerging semiconductors. The transconductance of these devices remains fairly constant from DC up to a frequency of the order of 1?kHz, a value determined by the process of ion transport between the electrolyte and the channel. These devices, which continue to work even after being crumpled, are predicted to be highly relevant as transducers in biosensing applications. PMID:23851620

Khodagholy, Dion; Rivnay, Jonathan; Sessolo, Michele; Gurfinkel, Moshe; Leleux, Pierre; Jimison, Leslie H.; Stavrinidou, Eleni; Herve, Thierry; Sanaur, Sebastien; Owens, Roisin M.; Malliaras, George G.

2013-01-01

302

High transconductance organic electrochemical transistors.  

PubMed

The development of transistors with high gain is essential for applications ranging from switching elements and drivers to transducers for chemical and biological sensing. Organic transistors have become well-established based on their distinct advantages, including ease of fabrication, synthetic freedom for chemical functionalization, and the ability to take on unique form factors. These devices, however, are largely viewed as belonging to the low-end of the performance spectrum. Here we present organic electrochemical transistors with a transconductance in the mS range, outperforming transistors from both traditional and emerging semiconductors. The transconductance of these devices remains fairly constant from DC up to a frequency of the order of 1 kHz, a value determined by the process of ion transport between the electrolyte and the channel. These devices, which continue to work even after being crumpled, are predicted to be highly relevant as transducers in biosensing applications. PMID:23851620

Khodagholy, Dion; Rivnay, Jonathan; Sessolo, Michele; Gurfinkel, Moshe; Leleux, Pierre; Jimison, Leslie H; Stavrinidou, Eleni; Herve, Thierry; Sanaur, Sébastien; Owens, Róisín M; Malliaras, George G

2013-01-01

303

Transmission electron microscopy study of Si ?-doped GaAs\\/AlGaAs\\/InGaAs\\/GaAs pseudomorphic high electron mobility transistor structures  

Microsoft Academic Search

A high electron mobility transistor (HEMT) structure grown by molecular beam epitaxy consisting of a 2-nm In0.3Ga0.7As channel limited by a thick GaAs layer at the bottom and a 5-nm Al0.3Ga0.7As spacer at the top has been characterised by transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). The carrier supplier of this structure is a Si ?-doped layer centred

S. I. Molina; T. Walther

1997-01-01

304

Stable gallium arsenide MIS capacitors and MIS field effect transistors by (NH4)2Sx treatment and hydrogenation using plasma deposited silicon nitride gate insulator  

Microsoft Academic Search

The beneficial effects of sulfur passivation of gallium arsenide (GaAs) surface by (NH4)2Sx chemical treatment and by hydrogenation of the insulator-GaAs interface using the plasma-enhanced chemical vapor-deposited (PECVD) silicon nitride gate dielectric film as the source of hydrogen are illustrated by fabricating Al\\/PECVD silicon nitride\\/n-GaAs MIS capacitors and metal insulator semiconductor field effect transistors (MISFET). Post metallization annealing (PMA) at

Kariyadan Remashan; K. N. Bhat

2002-01-01

305

Field effect transistor-self electrooptic effect device (FET-SEED) differential transimpedance amplifiers for two-dimensional optical data links  

Microsoft Academic Search

A 4×18 two-dimensional array of GaAs FET-SEED (field effect transistor-self electrooptic effect device) differential transimpedence receivers has been fabricated for application in massively parallel optical data link board-to-board interconnections. Several FET-SEED receiver arrays were tested and displayed a mean response of ~0.7 mV\\/?W, and were capable of >100 Mbps per channel operation. The mean receiver sensitivity for a BER of

Robert A. Novotny; Michael J. Wojcik; Anthony L. Lentine; Leo M. F. Chirovsky; L. A. D'Asaro; M. W. Focht; G. Guth; K. G. Glogovsky; R. Leibenguth; M. T. Asom; J. M. Freund

1995-01-01

306

Unsplit bipolar pulse forming line  

DOEpatents

A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

Rhodes, Mark A. (Pleasanton, CA)

2011-05-24

307

Depression and Bipolar Support Alliance  

NSDL National Science Digital Library

Living and coping with depression or bipolar disorder can be difficult, but there are a number of high-quality online resources that can be very useful to those with these conditions, or for those who work directly with these individuals. The homepage of the Depression and Bipolar Support Alliance (DBSA) can be of great help in this area, as their site includes everything from their �Real Recovery� podcasts to such basics as factsheets on both diseases. A good place to start here would be with any of the five primary sections, which include crisis intervention resources and recovery steps. Visitors can also view many of these materials in Spanish and they may also wish to sign up to receive the DBSA�s electronic newsletter.

2007-03-02

308

Depression and Bipolar Support Alliance  

NSDL National Science Digital Library

Living and coping with depression or bipolar disorder can be difficult, but there are a number of high-quality online resources that can be very useful to those with these conditions, or for those who work directly with these individuals. The homepage of the Depression and Bipolar Support Alliance (DBSA) can be of great help in this area, as their site includes everything from their "Real Recovery" podcasts to such basics as factsheets on both diseases. A good place to start here would be with any of the five primary sections, which include crisis intervention resources and recovery steps. Visitors can also view many of these materials in Spanish and they may also wish to sign up to receive the DBSA's electronic newsletter.

309

Excess mortality in bipolar disorders.  

PubMed

Bipolar disorder is associated with high mortality, and people with this disorder on average may die 10-20 years earlier than the general population. This excess and premature mortality continues to occur despite a large and expanding selection of treatment options dating back to lithium and now including anticonvulsants, antipsychotics, and evidence-based psychotherapies. This review summarizes recent findings on mortality in bipolar disorder, with an emphasis on the role of suicide (accounting for about 15% of deaths in this population) and cardiovascular disease (accounting for about 35-40% of deaths). Recent care models and treatments incorporating active outreach, integrated mental and physical health care, and an emphasis on patient self-management have shown promise in reducing excess mortality in this population. PMID:25194314

Miller, Christopher; Bauer, Mark S

2014-11-01

310

Bipolar Disorder: A Neurobiological Synthesis  

Microsoft Academic Search

\\u000a Bipolar disorder (BPD) is a common, chronic, recurrent mental illness affecting 1–2% of the general population (Goodwin and\\u000a Jamison 2007). Clinically, it is one of the most debilitating medical illnesses, and a growing number of recent studies indicate that\\u000a outcome is quite poor for many individuals with BPD. Afflicted patients generally experience high rates of relapse, a chronic\\u000a recurrent course,

Husseini K. Manji; Ioline D. Henter

311

Mitochondrial Dysfunction and Bipolar Disorder  

Microsoft Academic Search

\\u000a The mitochondrial dysfunction hypothesis was proposed to integrate various findings in bipolar disorder (BPD). This hypothesis\\u000a is supported by possible roles of maternal inheritance, comorbidity with mitochondrial diseases, the mechanism of action of\\u000a mood stabilizers, magnetic resonance spectroscopy, mitochondrial DNA mutations, gene expression analysis, and phenotypes of\\u000a animal models. Mitochondrial dysfunction is not specific to BPD but is common to

Tadafumi Kato

312

Am2900 Bipolar Microprocessor family  

Microsoft Academic Search

The Am2900 Bipolar Microprocessor family provides LSI building blocks applicable to numerous high-speed system configurations. The building blocks in this family handle the data path signals, the microprogram control functions, the input\\/output bus interconnections and the interrupt and timing\\/control requirements applicable to most digital systems. These building blocks are well suited for computer or central processor emulation, peripheral controllers, communications

John R. Mick

1975-01-01

313

Mutant Mouse Models of Bipolar Disorder  

Microsoft Academic Search

Bipolar disorder (also known as manic-depressive illness) is distinctive among psychiatric illnesses in that it is characterized\\u000a by spontaneously alternating episodes of depression and mania. Over the years, extensive research into the pathophysiology\\u000a of bipolar disorder has resulted in a growing understanding of the cellular, biochemical, and molecular changes associated\\u000a with bipolar disorder and its treatment. However, given its unique

Anneloes Dirks; Lucianne Groenink; Berend Olivier

314

Personality trait predictors of bipolar disorder symptoms  

Microsoft Academic Search

The purpose of the current investigation was to examine the personality predictors of bipolar disorder symptoms, conceptualized as one-dimensional (bipolarity) or two-dimensional (mania and depression). A psychiatric sample (N=370; 45% women; mean age 39.50 years) completed the Revised NEO Personality Inventory and the Minnesota Multiphasic Personality Inventory —2. A model in which bipolar symptoms were represented as a single dimension provided

Lena Catherine Quilty; Martin Sellbom; Jennifer Lee Tackett; Robert Michael Bagby

2009-01-01

315

Cognitive behavioral therapy for bipolar disorders Terapia comportamental cognitiva para pessoas com transtorno bipolar  

Microsoft Academic Search

Abstract Abstract Abstract Abstract Objectives and main techniques of cognitive behavior therapy for the treatment of bipolar disorder patients are described. K K K K Keywords eywords eywords eywords eywords: Cognitive therapy, Bipolar disorder\\/therapy; Bipolar disorder\\/psychology; Mood disorders; Psychotherapy

Francisco Lotufo Netoa

316

Lay Theories of Bipolar Disorder: the Causes, Manifestations and Cures for Perceived Bipolar Disorder  

Microsoft Academic Search

This study aimed to investigate lay theories of the cause and treatment of bipolar disorder, and the recognition of its symptoms. This questionnaire-based study included vignette descriptions of mental disorders and 70 items relating to bipolar disorder. It was completed by 173 participants. Bipolar disorder was recognized less than depression but at the same rate as schizophrenia. Contrary to previous

Adrian Furnham; Elizabeth Anthony

2010-01-01

317

Kleine-Levin syndrome and bipolar disorder Kleine-Levin syndrome and bipolar disorder  

E-print Network

by her psychiatrist to our bipolar expert center for recurrent and resistant major depression accordingKleine-Levin syndrome and bipolar disorder Kleine-Levin syndrome and bipolar disorder: a differential diagnosis of recurrent and resistant depression Pierre Alexis GEOFFROY1,3,4,5* , Isabelle ARNULF6

318

Problems in the boundaries of bipolar disorders.  

PubMed

Classical concepts of bipolarity (bipolar I and bipolar II) have sometimes been extended into a broader spectrum that includes a wide variety of conditions previously diagnosed as separate forms of psychopathology. Differential diagnosis remains important, particularly in personality disorders characterized by affective instability, and in behavior disorders affecting pre-pubertal children. In the absence of biological markers or other external sources of validity, as well as lack of evidence for response to pharmacological treatment when disorders are defined more broadly, the bipolar spectrum remains an unproven hypothesis. PMID:24930522

Paris, Joel

2014-08-01

319

Distinctions between bipolar and unipolar depression  

PubMed Central

This is a review of the studies comparing unipolar and bipolar depression, with focus on the course, symptomatology, neurobiology, and psychosocial literatures. These are reviewed with one question in mind: does the evidence support diagnosing bipolar and unipolar depressions as the same disorder or different? The current nomenclature of bipolar and unipolar disorders has resulted in research that compares these disorders as a whole, without considering depression separately from mania within bipolar disorder. Future research should investigate two broad categories of depression and mania as separate disease processes that are highly comorbid. PMID:15792852

Cuellar, Amy K.; Johnson, Sheri L.; Winters, Ray

2010-01-01

320

Doping Level Dependence of Transfer Characteristic of n-type Graphene Nanoribbon Field Effect Transistors  

NASA Astrophysics Data System (ADS)

By performing first principles calculations and electron transport simulations, we demonstrate that the transfer curves of graphene nanoribbon field effect transistors can be controlled by changing the concentration of potassium atoms and cobaltocene molecules doping, or nanoribbon edge carbon atoms substitution by nitrogen. We reveal that Dirac point shift downward from 0 to -12 V when the impurity concentration increase from 0 to 1.37%, while the transfer curves maintain bipolar characteristics with reasonably high on/off ratios. Moreover, we observed strong charge transfer from the adsorbed atoms and molecules that facilitates n-type characteristics in graphene nanoribbons. Thus, we suggest that an effective way to achieve tunable n-type graphene nanoribbons field effects transistors is to dope them with electron donors.

Wang, Lu; Qin, Rui; Zhou, Jing; Li, Hong; Zheng, Jiaxin; Lu, Jing; Mei, Wai-Ning; Nagase, Shigeru

2011-03-01

321

Bandwidth enhancement and optical performances of multiple quantum well transistor lasers  

E-print Network

A detailed rate-equation-based model is developed to study carrier transport effects on optical and electrical characteristics of the Multiple Quantum Well Heterojunction Bipolar Transistor Laser in time-domain. Simulation results extracted using numerical techniques in small-signal regime predict significant enhancement in device optical bandwidth when multiple quantum wells are used. Cavity length and base width are also modified to optimize the optoelectronic performances of the device. An optical bandwidth of \\approx 60GHz is achieved in the case of 5 quantum wells each of 70A widths and a cavity length of 200um.

Iman Taghavi; Hassan Kaatuzian; Jean-Pierre Leburton

2012-05-23

322

Bandwidth enhancement and optical performances of multiple quantum well transistor lasers  

E-print Network

A detailed rate-equation-based model is developed to study carrier transport effects on optical and electrical characteristics of the Multiple Quantum Well Heterojunction Bipolar Transistor Laser in time-domain. Simulation results extracted using numerical techniques in small-signal regime predict significant enhancement in device optical bandwidth when multiple quantum wells are used. Cavity length and base width are also modified to optimize the optoelectronic performances of the device. An optical bandwidth of \\approx 60GHz is achieved in the case of 5 quantum wells each of 70A widths and a cavity length of 200um.

Taghavi, Iman; Leburton, Jean-Pierre

2012-01-01

323

Simulation of novel complementary bipolar inverters for low-voltage high-speed ULSI  

NASA Astrophysics Data System (ADS)

Complementary bipolar (CBi) inverters on scaled down self-aligned transistors with highly-doped bases for advanced high-speed low-voltage low-power deep-submicron ULSI are considered and studied using a simulator PSPICE. A novel symmetrical transistor structure (STS) with undoped (lightly-doped) active base and nanometer regime, that can function as complementary n-p-n and p-n-p devices for CBi inverters at ultra-reduced supply voltages VEE, VEE=0.1-0.5 V, is investigated and simulated. It is shown that numerical mixed 2D-device-circuit simulator (DCSIM) for personal computer gives accurate knowledge of the static and dynamic properties of upward and downward self-aligned STS and CBi inverters eliminating the intermediate nonaccurate procedure of model electrical parameter extraction. This paper presents 2D numerical device-circuit simulations of the bipolar nanostructures and push-pull inverters on complementary STS with undoped active bases in ultra-low-voltage regime providing a high degree of integration, extremely high intrinsic speed and sufficiently high driving capacity. The switching problems for high-speed low-power low-action operations and optimization of sub-0.5 V Cbi inverters are studied.

Bubennikov, Alexander N.; Zykov, Andrey V.

2000-01-01

324

An ion-gated bipolar amplifier for ion sensing with enhanced signal and improved noise performance  

NASA Astrophysics Data System (ADS)

This work presents a proof-of-concept ion-sensitive device operating in electrolytes. The device, i.e., an ion-gated bipolar amplifier (IGBA), consists of a modified ion-sensitive field-effect transistor (ISFET) intimately integrated with a vertical bipolar junction transistor for immediate current amplification without introducing additional noise. With the current non-optimized design, the IGBA is already characterized by a 70-fold internal amplification of the ISFET output signal. This signal amplification is retained when the IGBA is used for monitoring pH variations. The tight integration significantly suppresses the interference of the IGBA signal by external noise, which leads to an improvement in signal-to-noise performance compared to its ISFET reference. The IGBA concept is especially suitable for biochips with millions of electric sensors that are connected to peripheral readout circuitry via extensive metallization which may in turn invite external interferences leading to contamination of the signal before it reaches the first external amplification stage.

Zhang, Da; Gao, Xindong; Chen, Si; Norström, Hans; Smith, Ulf; Solomon, Paul; Zhang, Shi-Li; Zhang, Zhen

2014-08-01

325

Design optimization of GaAs betavoltaic batteries  

Microsoft Academic Search

GaAs junctions are designed and fabricated for betavoltaic batteries. The design is optimized according to the characteristics of GaAs interface states and the diffusion length in the depletion region of GaAs carriers. Under an illumination of 10 mCi cm-2 63Ni, the open circuit voltage of the optimized batteries is about ~0.3 V. It is found that the GaAs interface states

Haiyanag Chen; Lan Jiang; Xuyuan Chen

2011-01-01

326

Sleep disturbances in pediatric bipolar disorder: A comparison between Bipolar I and Bipolar NOS  

Microsoft Academic Search

Introduction: The diagnosis of Bipolar Disorder (BD) in youths has been controversial, especially for the subtype BD Not Otherwise Specified (BD-NOS). In spite of growing evidence that sleep is a core feature of BD, few studies characterize and compare sleep disturbances in youth with BD type I (BD-I) and BD-NOS. Sleep disturbances are frequently reported in clinical descriptions of children

Argelinda Baroni; Mariely Hernandez; Marie Grant; Gianni Faedda

2012-01-01

327

Prediction of radiation damage effects in transistors  

NASA Technical Reports Server (NTRS)

Quantative relationships between radiation dosage to transistors and resultant damage are established. Calculation of these dose levels is based on high energy particle population data and analysis of the shielding effect provided by the enclosures surrounding a given transistor.

1967-01-01

328

A Cryogenic GaAs PHEMT/ Ferroelectric Ku-Band Tunable Oscillator  

NASA Technical Reports Server (NTRS)

A Ku-band tunable oscillator operated at and below 77 K is described. The oscillator is based on two separate technologies: a 0.25 mm GaAs pseudomorphic high electron mobility transistor (PHEMT) circuit optimized for cryogenic operation, and a gold microstrip ring resonator patterned on a thin ferroelectric (SrTiO3) film which was laser ablated onto a LaAlO3 substrate. A tuning range of up to 3% of the center frequency was achieved by applying dc bias between the ring resonator and ground plane. To the best of our knowledge, this is the first tunable oscillator based on a thin film ferroelectric structure demonstrated in the microwave frequency range. The design methodology of the oscillator and the performance characteristics of the tunable resonator are described.

Romanofsky, Robert R.; Miranda, Felix A.; VanKeuls, Fred W.

1998-01-01

329

Paper field effect transistor  

NASA Astrophysics Data System (ADS)

In this paper we report the use of a sheet of cellulose fiber-based paper as the dielectric layer used in oxide based semiconductor thin film field-effect transistors (FETs). In this new approach we are using the cellulose fiber-based paper in an "interstrate" structure since the device is build on both sides of the cellulose sheet. Such hybrid FETs present excellent operating characteristics such as high channel saturation mobility (>30 cm2/Vs), drain-source current on/off modulation ratio of approximately 104, near-zero threshold voltage, enhancement n-type operation and sub-threshold gate voltage swing of 0.8 V/decade. The cellulose fiber-based paper FETs characteristics have been measured in air ambient conditions and present good stability. The obtained results outpace those of amorphous Si TFTs and rival with the same oxide based TFTs produced on either glass or crystalline silicon substrates. The compatibility of these devices with large-scale/large-area deposition techniques and low cost substrates as well as their very low operating bias delineates this as a promising approach to attain high-performance disposable electronics like paper displays, smart labels, smart packaging, RFID and point-of-care systems for self analysis in bio-applications, among others.

Fortunato, E.; Correia, Nuno; Barquinha, Pedro; Costa, Cláudia; Pereira, Luís; Gonçalves, Gonçalo; Martins, Rodrigo

2009-02-01

330

GaAs Solar Cell Radiation Handbook  

NASA Technical Reports Server (NTRS)

The handbook discusses the history of GaAs solar cell development, presents equations useful for working with GaAs solar cells, describes commonly used instrumentation techniques for assessing radiation effects in solar cells and fundamental processes occurring in solar cells exposed to ionizing radiation, and explains why radiation decreases the electrical performance of solar cells. Three basic elements required to perform solar array degradation calculations: degradation data for GaAs solar cells after irradiation with 1 MeV electrons at normal incidence; relative damage coefficients for omnidirectional electron and proton exposure; and the definition of the space radiation environment for the orbit of interest, are developed and used to perform a solar array degradation calculation.

Anspaugh, B. E.

1996-01-01

331

New Gate Dielectric Oxides for GaAs and Other Semiconductors*  

NASA Astrophysics Data System (ADS)

It is well known that electrons move much faster in GaAs than in Si, and this attribute makes the GaAs-based metal oxide semiconductor field effect transistors (MOSFETs) very attractive for high-frequency, high-speed circuits applications. However, identifying a proper insulating oxide for GaAs has been a problem puzzling researchers over 35 years. Recently we discovered that the use of a mixed oxide dielectric Ga_2O_3(Gd_2O_3)^1 formed inversion and accumulation channels on GaAs surfaces, with a low interfacial density of states (D_it) of mid-10^10 cm-2eV-1. Subsequently, we have demonstrated the p- and n- inversion channel MOSFETs^2 and CMOS circuits^3. All oxides in this work were prepared by ultrahigh vacuum deposition from e-beam sources. The initial growth ( 10 Åof Ga_2O_3(Gd_2O_3) film on GaAs takes place from nucleating a thin epitaxial layer of pure Gd_2O_3. In fact, mono-domain, single crystalline Gd_2O3 films (? =12) can be grown on GaAs (100) surface in the (110) Mn_2O3 structure, and that show leakage currents as low as 10-4 A/cm^2 at 10 MV/cm for a film only 25 Åthick^4. We have extended our studies to other rare earth oxides and other semiconductors. For example, low-D_it GaN MOS diodes and GaN MOSFETs operated at 400^circC were obtained. The GaN MOSFET has potential applications in high power switching and high temperature device operation. More remarkably, we have found recently that another rare earth oxide, Y_2O3 (? = 18) showed excellent electrical properties as a gate dielectric for Si, to replace the current SiO_2, where the thickness is now approaching the quantum limit^5. *In collaboration with J. Kwo, A. R. Kortan, J. N. Baillargeon, J. P. Mannaerts, F. Ren, Y. C. Wang, T. S. Lay, H. Ng, R. Opila, K. L. Queeney, Y. J. Chabal, T. Boone, J. J. Krajewski, A. M. Sergent, J. M. Rosamilia, M. Passlack, D. W. Murphy, and A. Y. Cho. 1. M. Hong, et al, J. Vac. Sci. Technol. B14, 2297, (1996). 2. F. Ren et al, IEDM Technical Digest, p.943, (1996). 3. J. N. Baillargeon et al, unpublished. 4. M. Hong et al, Science, 283, 1897, (1999). 5. J. Kwo et al, submitted for publication.

Hong, M.

2000-03-01

332

Heterostructure unipolar spin transistors M. E. Flatta  

E-print Network

Heterostructure unipolar spin transistors M. E. Flattéa Optical Science and Technology Center semiconductor electronics and spin-based unipolar electronics by considering unipolar spin transistors electrons to the collector limits the performance of "homojunction" unipolar spin transistors, in which

Flatte, Michael E.

333

Electronics MOS Field-Effect Transistors  

E-print Network

ECEN 325 Electronics MOS Field-Effect Transistors Dr. Aydin Ilker Kar¸silayan Texas A&M University. Kar¸silayan - MOS Field-Effect Transistors 1 #12;CMOS Physical StructureCMOS Physical Structure Cross 325 Electronics - Aydin I. Kar¸silayan - MOS Field-Effect Transistors 2 #12;TAMU-ELEN-325 J. Silva

Palermo, Sam

334

Single Carbon Nanotube Transistor at GHz Frequency  

E-print Network

Single Carbon Nanotube Transistor at GHz Frequency J. Chaste,, L. Lechner,£ P. Morfin,, G. Fe operation of top-gated single carbon nanotube transistors. From transmission measurements in the 0.1-1.6 GHz effect transistors (CNT-FETs) are very attractive as ultimate, quantum limited devices. In particular

Plaçais, Bernard

335

Photoresponsive nanoscale columnar transistors Xuefeng Guoa,1  

E-print Network

Photoresponsive nanoscale columnar transistors Xuefeng Guoa,1 , Shengxiong Xiaob , Matthew Myersb reports a general methodology for making stable high-performance photosensitive field effect transistors nanostructures with a diameter similar to that of SWNTs and then form nanoscale columnar transistors. To rule out

Hone, James

336

Integration of Cell Membranes and Nanotube Transistors  

E-print Network

Integration of Cell Membranes and Nanotube Transistors Keith Bradley, Alona Davis, Jean. As the nanoelectronic device, we use a nanotube network transistor, which incorporates many individual nanotubes as transistors, and that the two systems interact. Further, we use the interaction to study the charge

Gruner, George

337

The Resonant Body Transistor Dana Weinstein,*,  

E-print Network

The Resonant Body Transistor Dana Weinstein,*, and Sunil A. Bhave Cornell University, 405 Phillips Hall, Ithaca, New York 14853 ABSTRACT This paper introduces the resonant body transistor (RBT), a silicon-based dielectrically transduced nanoelectromechanical (NEM) resonator embedding a sense transistor

Afshari, Ehsan

338

Electroluminescence from a Single-Nanocrystal Transistor  

E-print Network

Electroluminescence from a Single-Nanocrystal Transistor Mark S. Gudiksen, Kristin N. Maher, Lian September 8, 2005 ABSTRACT We report the fabrication and characterization of light-emitting transistors- emitting transistors incorporating individual CdSe nano- crystals. Unlike the two-terminal devices employed

Heller, Eric

339

DECISION DIAGRAMS AND PASS TRANSISTOR LOGIC SYNTHESIS  

E-print Network

DECISION DIAGRAMS AND PASS TRANSISTOR LOGIC SYNTHESIS V. Bertacco S. Minato P. Verplaetse L. Benini by ARPA, under grant No. DABT63-95-C-0049. #12;Decision Diagrams and Pass Transistor Logic Synthesis V transistors and domino logic. The synthesis of these cells is based on BDD and ZBDD representations

De Micheli, Giovanni

340

Circuit Design with Independent Double Gate Transistors  

Microsoft Academic Search

Circuits with transistors using independently controlled gates have been designed to reduce the number of transistors and to increase the logic density per area. This paper proposed a full adder and substractor circuit with novel Vertical Slit Field Effect Transistor and unique independent double gate properties to demonstrate the possible advantages for independent double gate circuits. With the help of

Viranjay M. Srivastava; Nitant Saubagya; G. Singh

2010-01-01

341

Bio-organic field effect transistors  

Microsoft Academic Search

This paper reports on the use of new DNA-based biopolymers as the semiconducting layer in field effect transistors. Thin-film field effect transistor (FET) structures are fabricated with two different DNA-biopolymers as semiconductor layers, and two different field effect transistor structures are studied. Current voltage characteristics of the FETs show that the devices are operating in depletion mode.

Carrie M. Bartsch; Guru Subramanyam; James G. Grote; Kristi M. Singh; Rajesh R. Naik; Birendra Singh; Niyazi S. Sariciftci

2007-01-01

342

Optically-Activated GaAs Switches for Ground Penetrating Radar and Firing Set Applications  

SciTech Connect

Optically activated, high gain GaAs switches are being tested for many different applications. TWO such applications are ground penetrating radar (GPR) and firing set switches. The ability of high gain GaAs Photoconductive Semiconductor Switches (PCSs) to deliver fast risetime pulses makes them suitable for their use in radars that rely on fast impulses. This type of direct time domain radar is uniquely suited for the detection of buried items because it can operate at low frequency, high average power, and close to the ground, greatly increasing power on target. We have demonstrated that a PCSs based system can be used to produce a bipolar waveform with a total duration of about 6 ns and with minimal ringing. Such a pulse is radiated and returns from a 55 gallon drum will be presented. For firing sets, the switch requirements include small size, high current, dc charging, radiation hardness and modest longevity. We have switched 1 kA at 1 kV and 2.8 kA at 3 kV dc charge.

Aurand, J.; Brown, D.J.; Carin, L.; Denison, G.J.; Helgeson, W.D.; Loubriel, G.M.; Mar, A.; O'Malley, M.W.; Rinehart, L.F.; Zutavern, F.J.

1999-07-14

343

GaAs photoconductive semiconductor switch  

DOEpatents

A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices.

Loubriel, Guillermo M. (Sandia Park, NM); Baca, Albert G. (Albuquerque, NM); Zutavern, Fred J. (Albuquerque, NM)

1998-01-01

344

GaAs photoconductive semiconductor switch  

DOEpatents

A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device is disclosed. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices. 5 figs.

Loubriel, G.M.; Baca, A.G.; Zutavern, F.J.

1998-09-08

345

GaAs nanoneedles grown on sapphire  

NASA Astrophysics Data System (ADS)

Heterogeneous integration of dissimilar single crystals is of intense research interests. Lattice mismatch has been the most challenging bottleneck which limits the growth of sufficient active volume for functional devices. Here, we report self-assembled, catalyst-free, single crystalline GaAs nanoneedles grown on sapphire substrates with 46% lattice mismatch. The GaAs nanoneedles have a 2-3 nm tip, single wurtzite phase, excellent optical quality, and dimensions scalable with growth time. The needles have the same sharp, hexagonal pyramid shape from ˜100 nm (1.5 min growth) to ˜9 ?m length (3 h growth).

Chuang, Linus C.; Moewe, Michael; Ng, Kar Wei; Tran, Thai-Truong D.; Crankshaw, Shanna; Chen, Roger; Ko, Wai Son; Chang-Hasnain, Connie

2011-03-01

346

Quality of Life in Pediatric Bipolar Disorder  

Microsoft Academic Search

OBJECTIVE.Bipolar disorder is a common mood disorder associated with significant disability and impairment in quality of life in adults. Little research has examined the impact of the disorder on quality of life in children and adolescents. The current study examines the quality of life in children and adolescents with bipolar disorder compared with other physical and psychiatric illnesses. METHODS.This study

Andrew J. Freeman; Eric A. Youngstrom; Erin Michalak; Rebecca Siegel; Oren I. Meyers; Robert L. Findling

2009-01-01

347

Childhood Onset Bipolar Disorder: Pharmacological Treatment Overview  

Microsoft Academic Search

The diagnosis of Bipolar Disorder is still quite controversial in child psychiatry: its boundaries remain uncertain while treatment is based as much on research as on clinical wisdom. Several questions on the treatment of Bipolar Disorder in children await an answer: 1)Does age affect treatments effectiveness and side effects? 2) Can mania be induced by Antidepressant or Stimulant treatment, and

Gianni L. Faedda

2004-01-01

348

Fuel Cell Stack Components BipolarPlate  

E-print Network

· Thermal and water management $10 Other Bipolar Plates Membranes Electrodes $25 $5 $5 Fuel Cell Power (oral, continued) De Nora North America, Inc. 3M UTC Fuel Cells Superior MicroPowders Fuel Cell Energy for Metallic Bipolar Plates · Carbon Foam for Fuel Cell Humidification · High Temperature Proton Exchange

349

Thomson semiconductors bipolar IC strategy to 1986  

NASA Astrophysics Data System (ADS)

The strategy to develop and market bipolar integrated circuits through 1986 by thomson semiconductors is discussed. Current technology and future research on prototype microprocessors using bipolar integrated circuits is evaluated. The physical properties of the circuits such as heat dissipation, energy consumption rates and response times are studied.

Dellamussia, J. P.

1984-04-01

350

Bipolar Disorder in School-Age Children  

ERIC Educational Resources Information Center

This article examines the individual components of bipolar disorder in children and the behaviors that can escalate as a result of misdiagnosis and treatment. The brain/behavior relationship in bipolar disorders can be affected by genetics, developmental failure, or environmental influences, which can cause an onset of dramatic mood swings and…

Olson, Patricia M.; Pacheco, Mary Rae

2005-01-01

351

Bipolar depression: pharmacotherapy and related therapeutic strategies  

Microsoft Academic Search

The depressed phase of bipolar affective disorder is a significant cause of suffering, disability, and mortality and represents a major challenge to treating clinicians. This article first briefly reviews the phenomenology and clinical correlates of bipolar depression and then focuses on the major pharmacological treatment options. We strongly recommend use of mood stabilizers as the first-line treatment for the type

Michael E Thase; Gary S Sachs

2000-01-01

352

Dynamic avalanche in bipolar power devices  

Microsoft Academic Search

In bipolar power devices, remaining plasma is extracted during turn-off. In high-voltage devices, even at moderate conditions dynamic avalanche caused by the free carriers appears. Strong dynamic avalanche leads to filament formation. The effect must not be destructive as long as the filaments can move. Effects which are common in the bipolar devices GTO, GCT, IGBT and power diode are

Josef Lutz; Roman Baburske

353

Modeling "Soft" Errors in Bipolar Integrated Circuits  

NASA Technical Reports Server (NTRS)

Mathematical models represent single-event upset in bipolar memory chips. Physics of single-event upset in integrated circuits discussed in theoretical paper. Pair of companion reports present mathematical models to predict critical charges for producing single-event upset in bipolar randomaccess memory (RAM) chips.

Zoutendyk, J.; Benumof, R.; Vonroos, O.

1985-01-01

354

Bipolar Ag-Zn battery  

NASA Astrophysics Data System (ADS)

The silver-zinc (AgZn) battery system has been unique in its ability to safely satisfy high power demand applications with low mass and volume. However, a new generation of defense, aerospace, and commercial applications will impose even higher power demands. These new power demands can be satisfied by the development of a bipolar battery design. In this configuration the power consuming, interelectrode current conductors are eliminated while the current is then conducted via the large cross-section electrode substrate. Negative and positive active materials are applied to opposite sides of a solid silver foil substrate. In addition to reducing the weight and volume required for a specified power level, the output voltage performance is also improved as follows. Reduced weight through: elimination of the plastic cell container; elimination of plate leads and intercell connector; and elimination of internal plate current collector. Increased voltage through: elimination of resistance of current collector; elimination of resistance of plate lead; and elimination of resistance of intercell connector. EPI worked previously on development of a secondary bipolar silver zinc battery. This development demonstrated the electrical capability of the system and manufacturing techniques. One difficulty with this development was mechanical problems with the seals. However, recent improvements in plastics and adhesives should eliminate the major problem of maintaining a seal around the periphery of the bipolar module. The seal problem is not as significant for a primary battery application or for a requirement for only a few discharge cycles. A second difficulty encountered was with activation (introducing electrolyte into the cell) and with venting gas from the cell without loss of electrolyte. During previous work, the following projections for energy density were made from test data for a high power system which demonstrated in excess of 50 discharge/charge cycles. Projected system power = 100 kilowatts; discharge time = 30 seconds; discharge current density = 1.75 amps/sq in.; system weight = 86 lbs (9.7 WH/lb); and system volume = 1071 cu. in. (.78 WH/cu. in.). EPI is currently working on a development program to produce a bipolar silver-zinc battery design for NASA. The potential application would be to power electromechanical actuators for space launch vehicles.

Giltner, L. John

1994-02-01

355

Bipolar Ag-Zn battery  

NASA Technical Reports Server (NTRS)

The silver-zinc (AgZn) battery system has been unique in its ability to safely satisfy high power demand applications with low mass and volume. However, a new generation of defense, aerospace, and commercial applications will impose even higher power demands. These new power demands can be satisfied by the development of a bipolar battery design. In this configuration the power consuming, interelectrode current conductors are eliminated while the current is then conducted via the large cross-section electrode substrate. Negative and positive active materials are applied to opposite sides of a solid silver foil substrate. In addition to reducing the weight and volume required for a specified power level, the output voltage performance is also improved as follows. Reduced weight through: elimination of the plastic cell container; elimination of plate leads and intercell connector; and elimination of internal plate current collector. Increased voltage through: elimination of resistance of current collector; elimination of resistance of plate lead; and elimination of resistance of intercell connector. EPI worked previously on development of a secondary bipolar silver zinc battery. This development demonstrated the electrical capability of the system and manufacturing techniques. One difficulty with this development was mechanical problems with the seals. However, recent improvements in plastics and adhesives should eliminate the major problem of maintaining a seal around the periphery of the bipolar module. The seal problem is not as significant for a primary battery application or for a requirement for only a few discharge cycles. A second difficulty encountered was with activation (introducing electrolyte into the cell) and with venting gas from the cell without loss of electrolyte. During previous work, the following projections for energy density were made from test data for a high power system which demonstrated in excess of 50 discharge/charge cycles. Projected system power = 100 kilowatts; discharge time = 30 seconds; discharge current density = 1.75 amps/sq in.; system weight = 86 lbs (9.7 WH/lb); and system volume = 1071 cu. in. (.78 WH/cu. in.). EPI is currently working on a development program to produce a bipolar silver-zinc battery design for NASA. The potential application would be to power electromechanical actuators for space launch vehicles.

Giltner, L. John

1994-01-01

356

Facile synthesis and growth mechanism of Ni-catalyzed GaAs nanowires on non-crystalline substrates  

NASA Astrophysics Data System (ADS)

GaAs nanowires (NWs) have been extensively explored for next generation electronics, photonics and photovoltaics due to their direct bandgap and excellent carrier mobility. Typically, these NWs are grown epitaxially on crystalline substrates, which could limit potential applications requiring high growth yield to be printable or transferable on amorphous and flexible substrates. Here, utilizing Ni as a catalytic seed, we successfully demonstrate the synthesis of highly crystalline, stoichiometric and dense GaAs NWs on amorphous SiO2 substrates. Notably, the NWs are found to grow via the vapor-solid-solid (VSS) mechanism with non-spherical NiGa catalytic tips and low defect densities while exhibiting a narrow distribution of diameter (21.0 ± 3.9 nm) uniformly along the entire length of the NW (>10 µm). The NWs are then configured into field-effect transistors showing impressive electrical characteristics with ION/IOFF > 103, which further demonstrates the purity and crystal quality of NWs obtained with this simple synthesis technique, compared to the conventional MBE or MOCVD grown GaAs NWs.

Han, Ning; Wang, Fengyun; Hui, Alvin T.; Hou, Jared J.; Shan, Guangcun; Xiu, Fei; Hung, TakFu; Ho, Johnny C.

2011-07-01

357

Electrical detection of the biological interaction of a charged peptide via gallium arsenide junction-field-effect transistors  

PubMed Central

GaAs junction-field-effect transistors (JFETs) are utilized to achieve label-free detection of biological interaction between a probe transactivating transcriptional activator (TAT) peptide and the target trans-activation-responsive (TAR) RNA. The TAT peptide is a short sequence derived from the human immunodeficiency virus-type 1 TAT protein. The GaAs JFETs are modified with a mixed adlayer of 1-octadecanethiol (ODT) and TAT peptide, with the ODT passivating the GaAs surface from polar ions in physiological solutions and the TAT peptide providing selective binding sites for TAR RNA. The devices modified with the mixed adlayer exhibit a negative pinch-off voltage (VP) shift, which is attributed to the fixed positive charges from the arginine-rich regions in the TAT peptide. Immersing the modified devices into a TAR RNA solution results in a large positive VP shift (>1 V) and a steeper subthreshold slope (?80 mV?decade), whereas “dummy” RNA induced a small positive VP shift (?0.3 V) without a significant change in subthreshold slopes (?330 mV?decade). The observed modulation of device characteristics is analyzed with analytical modeling and two-dimensional numerical device simulations to investigate the electronic interactions between the GaAs JFETs and biological molecules. PMID:19484151

Lee, Kangho; Nair, Pradeep R.; Alam, Muhammad A.; Janes, David B.; Wampler, Heeyeon P.; Zemlyanov, Dmitry Y.; Ivanisevic, Albena

2008-01-01

358

Silicon-compatible compound semiconductor tunneling field-effect transistor for high performance and low standby power operation  

NASA Astrophysics Data System (ADS)

In this study, we propose and characterize by simulation a silicon-compatible compound semiconductor tunneling field-effect transistor (TFET) based on germanium (Ge)/gallium arsenide (GaAs) heterojunction aiming the various integrated systems on silicon substrate. By introducing Ge as p+ source and GaAs as the high-mobility channel and n+ drain materials, we maximize on-state current (Ion) and minimize off-state current (Ioff) to obtain a TFET for high performance and low standby power capabilities. The effects of physical parameters such as aluminum content, source-gate overlap length, and gate workfunction on device performance were examined thoroughly. Further, we evaluate its radio frequency performance and confirm that it shows superb current and power gain characteristics.

Cho, Seongjae; Man Kang, In; Kamins, Theodore I.; Park, Byung-Gook; Harris, James S.

2011-12-01

359

Neurocognitive function in bipolar disorder: a comparison between bipolar I and II disorder and matched controls  

PubMed Central

Background Cognitive deficits have been documented in patients with bipolar disorder. Further, it has been suggested that the degree and type of cognitive impairment differ between bipolar I and bipolar II disorder, but data is conflicting and remains inconclusive. This study aimed to clarify the suggested differences in cognitive impairment between patients with bipolar I and II disorder in a relatively large, clinically stable sample while controlling for potential confounders. Methods 67 patients with bipolar I disorder, 43 with bipolar II disorder, and 86 randomly selected population-based healthy controls were compared. A number of neuropsychological tests were administered, assessing verbal and visual memory and executive functions. Patients were in a stable phase during testing. Results Patients with bipolar type I and type II were cognitively impaired compared to healthy controls, but there were no statistically significant differences between the two subtypes. The strongest predictor of cognitive impairment within the patient group was current antipsychotic treatment. Conclusions The present study suggests that the type and degree of cognitive dysfunction is similar in bipolar I and II patients. Notably, treatment with antipsychotics - but not a history of psychosis - was associated with more severe cognitive impairment. Given that patients with bipolar I disorder are more likely to be on antipsychotic drugs, this might explain why some previous studies have found that patients with type I bipolar disorder are more cognitively impaired than those with type II. PMID:23758923

2013-01-01

360

Viruses, schizophrenia, and bipolar disorder.  

PubMed Central

The hypothesis that viruses or other infectious agents may cause schizophrenia or bipolar disorder dates to the 19th century but has recently been revived. It could explain many clinical, genetic, and epidemiologic aspects of these diseases, including the winter-spring birth seasonality, regional differences, urban birth, household crowding, having an older sibling, and prenatal exposure to influenza as risk factors. It could also explain observed immunological changes such as abnormalities of lymphocytes, proteins, autoantibodies, and cytokines. However, direct studies of viral infections in individuals with these psychiatric diseases have been predominantly negative. Most studies have examined antibodies in blood or cerebrospinal fluid, and relatively few studies have been done on viral antigens, genomes, cytopathic effect on cell culture, and animal transmission experiments. Viral research on schizophrenia and bipolar disorder is thus comparable to viral research on multiple sclerosis and Parkinson's disease: an attractive hypothesis with scattered interesting findings but no clear proof. The application of molecular biological techniques may allow the identification of novel infectious agents and the associations of these novel agents with serious mental diseases. PMID:7704891

Yolken, R H; Torrey, E F

1995-01-01

361

Image transfer in photorefractive GaAs  

NASA Technical Reports Server (NTRS)

Image transfer from one beam to the other using counterpropagation beam coupling in GaAs was demonstrated. Good image quality was achieved. The results also reveal that local birefringence due to the residual stress/strain field in the crystal can degrade the image quality.

Cheng, Li-Jen; Gheen, Gregory; Rau, Mann-Fu; Wang, Faa-Ching

1987-01-01

362

GaAs Solar Cell Radiation Handbook  

NASA Technical Reports Server (NTRS)

History of GaAs solar cell development is provided. Photovoltaic equations are described along with instrumentation techniques for measuring solar cells. Radiation effects in solar cells, electrical performance, and spacecraft flight data for solar cells are discussed. The space radiation environment and solar array degradation calculations are addressed.

Anspaugh, B. E.

1996-01-01

363

GaAs distributed feedback injection lasers  

Microsoft Academic Search

The paper is concerned with the fabrication of GaAs corrugated waveguide lasers which can be used as light sources and are compatible with planar technology. Particular attention is devoted to the design and operation of distributed feedback injection (DFB) lasers based on a periodic perturbation in the refractive index or in the gain (or loss) of the guiding medium; this

A. Katzir; A. Yariv; H. W. Yen; M. Nakamura; K. Aiki; J.-I. Umeda

1975-01-01

364

Pediatric Bipolar Disorder: An issue for Child Welfare  

Microsoft Academic Search

A new diagnosis for children has emerged in the last decade: Pediatric Bipolar Disorder. Children who would have in the past been given other diagnoses are now being relabeled as Pediatric Bipolar. Drugs prescribed for adult Bipolar Disorder are being prescribed for children. The case for delaying pharmacological intervention for treatment of Bipolar Disorder, particularly among young children, is considered.

Jill Littrell; Peter Lyons

2010-01-01

365

Bipolar II Disorder: Symptoms, Course, and Response to Treatment  

Microsoft Academic Search

The authors provide an overview of the diagnosis, course, and treat- ment of bipolar II disorder, a distinct subtype that is often misdiag- nosed as unipolar depression or bipolar I disorder. They discuss re- search suggesting that underdiagnosis of bipolar II disorder reflects a failure to identify subthreshold expression of mania (hypomania). The course of bipolar II disorder is different

Glenda M. MacQueen; Trevor Young

2001-01-01

366

Process study of ZEP520 positive electron-beam resist and its application in single-electron transistor  

NASA Astrophysics Data System (ADS)

The process of resist is of great importance to the resolution of e-beam direct-writing exposure. ZEP520 is an excellent positive e-beam resist, which has high resolution, high sensitivity, high contrast as well as good dry etch resistance. In this paper, the e-beam exposure process of ZEP520 on Si and GaAs substrates and its application in nanoelectrode-pair and single-electron transistor have been studied. On Si substrate, the contrast, sensitivity and resolution of ZEP520 have been investigated in detail, and the influence of exposure dose and resist thickness on the size of ZEP520 patterns has been discussed. The contrast of 425nm-thick ZEP520 on Si is 2.70. The sensitivity of ZEP520 is <5 ?C/cm2. The size of ZEP520 lines and circular holes decreases with exposure dose decreasing and thickness increasing. 70 nm wide lines and 110-nm-diameter dots can be exposed on Si substrate using 110 nm thick ZEP520. The flaws of ZEP520 on GaAs can be eliminated by fore-baking the GaAs substrate; and 130 nm wide lines can be exposed on GaAs using ZEP520. In regard to application, a nanoelectrode-pair with a 60 nm space has been fabricated using ZEP520. And a kind of in-plane singe-electron transistor (SET) has also been fabricated on silicon-on-insulator (SOI) substrate, which has a 110 nm wide Si Coulomb island and shows Clear Coulomb staircases in Ids from the Ids-Vds characteristics and differential conductance (dIds/dVds) oscillations from the dIds/dVds-Vds characteristics at 2 K.

Long, Shibing; Li, Zhigang; Zhao, Xinwei; Chen, Baoqin; Liu, Ming

2005-01-01

367

Evaluation of silicon-germanium (SiGe) bipolar technologies for use in an upgraded atlas detector  

NASA Astrophysics Data System (ADS)

Silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technologies promise several advantages over CMOS for the front-end readout electronics for the ATLAS upgrade. We have evaluated the relative merits of the latest generations of IBM SiGe HBT BiCMOS technologies, the 8WL and 8HP platforms. These 130 nm SiGe technologies show promise to operate at lower power than do CMOS technologies and would provide a viable alternative for the silicon strip detector and liquid argon calorimeter upgrades, provided that the radiation tolerance studies at multiple gamma and neutron irradiation levels, included in this investigation, show them to be sufficiently radiation tolerant.

Ullán, M.; Rice, J.; Brooijmans, G.; Cressler, J. D.; Damiani, D.; Díez, S.; Gadfort, T.; Grillo, A. A.; Hackenburg, R.; Hare, G.; Jones, A.; Kierstead, J.; Kononenko, W.; Mandi?, I.; Martinez-McKinney, F.; Metcalfe, J.; Newcomer, F. M.; Parsons, J. A.; Phillips, S.; Rescia, S.; Sadrozinski, H. F.-W.; Seiden, A.; Spencer, E.; Spieler, H.; Sutton, A. K.; Tazawa, Y.; Wilder, M.; Wulf, E.

2009-06-01

368

Risk for Suicidal Ideation Among the Offspring of Bipolar Parents: Results From the Bipolar Offspring Study (BIOS)  

Microsoft Academic Search

The objective of the study was to examine rates and identify risk factors for suicidal ideation among offspring of parents with bipolar disorder. Subjects included 388 offspring of parents with bipolar disorder and 250 offspring of matched community controls enrolled in the Pittsburgh Bipolar Offspring Study (BIOS). Offspring of bipolar probands displayed greater rates of lifetime suicidal ideation than offspring

Tina R. Goldstein; Mihaela Obreja; Wael Shamseddeen; Satish Iyengar; David A. Axelson; Benjamin I. Goldstein; Kelly Monk; Mary Beth Hickey; Dara Sakolsky; David J. Kupfer; David A. Brent; Boris Birmaher

2011-01-01

369

Reduced Threshold Current in Bipolar Diode Lasers by Non-square Quantum Well Growth  

NASA Astrophysics Data System (ADS)

By device simulation, it is shown that non-square quantum well growth (well shaping) provides a means for reducing the threshold current of bipolar quantum well diode lasers. Calculations of subband structure, optical matrix elements and laser gain are performed based on a 4-band (electron, heavy-hole, light-hole, split-off-hole) Hamiltonian with Burt-Foreman Hermitianization. A non-optimized, compressively strained, InGaAs-AlGaAs (on GaAs) shaped well laser, operating at 0.97?m is predicted to show improvements in both radiative and non-radiative current performance compared to a device based on an optimal square quantum well of the same well width and emission wavelength. These improvements result from modification of subband structure giving greater subband separation in the shaped well than in the square well.

Kaduki, K. A.; Ghiti, A.; Batty, W.; Allsopp, D. W. E.

370

Impact of Bipolar Disorder on the Family  

PubMed Central

Objective: Our retrospective analysis compared costs and patterns of health care utilization by families that included a member with bipolar disorder (“bipolar families”) and by families without serious psychiatric disease (“control families”). Methods: We used the MarketScan Commercial Claims and Encounters Database covering January 1998 through December 2002. International Classification of Diseases (ICD-9-CM) codes were used to identify individuals with bipolar disorder and link them to their family members. Bipolar families were matched in a ratio of 1:3 to families without a serious mental illness. We calculated and statistically compared the mean annual use of resources and health care costs for each group, including the individual with bipolar disorder. We used a multivariate model to test the effect of demographic and health care variables on the impact of total health care expenditures. Results: Families with a member with bipolar disorder (n = 43,448), compared with matched families (n = 122,769), made significantly more outpatient physician visits (24 vs. eight; P < 0.001), more inpatient hospital stays (1 vs. 0.3; P < 0.001), and more prescription medications (24 vs. 7.8; P < 0.001). Total annual health care costs were more than three-fold higher for bipolar families ($4,664), compared with matched families ($1,376) (P < 0.001). The multivariate model controlled for family size and comorbidities, indicating significantly higher total health care costs for families with one or more persons with bipolar disorder than for matched families without serious mental illness. Conclusion: These results indicate that bipolar disorder has a significant financial impact on families in addition to the individual with the diagnosis. PMID:19749991

Chatterton, Mary Lou; Ke, Xiongkan; Lewis, Barbara Edelman; Rajagopalan, Krithika; Lazarus, Arthur

2008-01-01

371

Monolithically integrated GaAs thyristor-transistor as a hardened optically-triggered switch  

SciTech Connect

Optically-triggered thyristors are hardened to high x-ray dose rates by the addition of a monolithically integrated compensating phototransistor. Tests of these devices show that sensitivity to radiation-induced switching is reduced by a factor of ten compared to conventional two-terminal thyristors (to 2 {times} 10{sup 9} Rad (Si)/sec). 3 refs., 5 figs.

Carson, R.F.; Hughes, R.C.; Weaver, H.T.; Brennan, T.M.; Hammons, B.E.

1990-01-01

372

Looking for bipolar spectrum psychopathology: identification and expression in daily life.  

E-print Network

??Current clinical and epidemiological research provides support for a continuum of bipolar psychopathology: a bipolar spectrum that ranges from subclinical manifestations to full-blown bipolar disorders.… (more)

Armistead, Molly S.

2010-01-01

373

The Child Bipolar Questionnaire (CBQ) A Screening Instrument for Juvenile-onset Bipolar Disorder  

Microsoft Academic Search

In order to address the significant gap in available psychiatric rating scale instruments designed to assess juvenile-onset bipolar disorder symptoms, the Juvenile Bipolar Research Foundation (JBRF) has supported the development of an assessment instrument for this purpose. This scale, called the Child Bipolar Questionnaire (CBQ), is a 65-item behavioral assessment tool. Preliminary data indicate that the CBQ has adequate-to- excellent

Demitri F. Papolos; Melissa Cockerham; John Hennon

374

Cannabis Use and Bipolar Disorder: Bipolar Disorder Case Identification and Cannabis Use Risk Assessment: A Dissertation.  

E-print Network

??Bipolar disorders (BD) are characterized by symptoms of grandiosity, decreased need for sleep, pressure to keep talking, flight of ideas, distractibility, increased goal-directed activities, psychomotor… (more)

McCabe, Patrick J.

2011-01-01

375

Composite substrate for bipolar electrodes  

DOEpatents

Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the present invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process. 4 figs.

Tekkanat, B.; Bolstad, J.J.

1992-12-22

376

Composite substrate for bipolar electrodes  

DOEpatents

Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the pesent invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process.

Tekkanat, Bora (Milwaukee, WI); Bolstad, James J. (Shorewood, WI)

1992-12-22

377

Antidepressant chronotherapeutics for bipolar depression  

PubMed Central

Chronotherapeutics refers to treatments based on the principles of circadian rhythm organization and sleep physiology, which control the exposure to environmental stimuli that act on biological rhythms, in order to achieve therapeutic effects in the treatment of psychiatric conditions. It includes manipulations of the sleep-wake cycle such as sleep deprivation and sleep phase advance, and controlled exposure to light and dark. The antidepressant effects of chronotherapeutics are evident in difficult-to-treat conditions such as bipolar depression, which has been associated with extremely low success rates of antidepressant drugs in naturalistic settings and with stable antidepressant response to chronotherapeutics in more than half of the patients. Recent advances in the study of the effects of chronotherapeutics on neurotransmitter systems, and on the biological clock machinery, allow us to pinpoint its mechanism of action and to transform it from a neglected or “orphan” treatment to a powerful clinical instrument in everyday psychiatric practice. PMID:23393416

Benedetti, Francesco

2012-01-01

378

Comorbidity in Pediatric Bipolar Disorder  

PubMed Central

Synopsis A growing literature shows the pervasiveness and importance of comorbidity in youth with bipolar disorder (BPD). For instance, up to 90% of youth with BPD have been described to manifest comorbidity with attention deficit hyperactivity disorder. Multiple anxiety, substance use, and disruptive behavior disorders are the other most commonly reported comorbidities with BPD. Moreover, important recent data highlights the importance of obsessive compulsive and pervasive developmental illness in the context of BPD. Data suggests that not only special developmental relationships are operant in context to comorbidity, but also that the presence of comorbid disorders with BPD results in a more severe clinical condition. Moreover, the presence of comorbidity has therapeutic implications for the treatment response for both BPD and the associated comorbid disorder. Future longitudinal studies to address the relationship and the impact of comorbid disorders on course and therapeutic response over time are required in youth with BPD. PMID:19264265

Joshi, Gagan; Wilens, Timothy

2013-01-01

379

The Integration and Applications of Organic Thin Film Transistors and Ferroelectric Polymers  

NASA Astrophysics Data System (ADS)

Organic thin film transistors and ferroelectric polymer (polyvinylidene difluoride) sheet material are integrated to form various sensors for stress/strain, acoustic wave, and Infrared (heat) sensing applications. Different from silicon-based transistors, organic thin film transistors can be fabricated and processed in room-temperature and integrated with a variety of substrates. On the other hand, polyvinylidene difluoride (PVDF) exhibits ferroelectric properties that are highly useful for sensor applications. The wide frequency bandwidth (0.001 Hz to 10 GHz), vast dynamic range (100n to 10M psi), and high elastic compliance (up to 3 percent) make PVDF a more suitable candidate over ceramic piezoelectric materials for thin and flexible sensor applications. However, the low Curie temperature may have impeded its integration with silicon technology. Organic thin film transistors, however, do not have the limitation of processing temperature, hence can serve as transimpedance amplifiers to convert the charge signal generated by PVDF into current signal that are more measurable and less affected by any downstream parasitics. Piezoelectric sensors are useful for a range of applications, but passive arrays suffer from crosstalk and signal attenuation which have complicated the development of array-based PVDF sensors. We have used organic field effect transistors, which are compatible with the low Curie temperature of a flexible piezoelectric polymer,PVDF, to monolithically fabricate transimpedance amplifiers directly on the sensor surface and convert the piezoelectric charge signal into a current signal which can be detected even in the presence of parasitic capacitances. The device couples the voltage generated by the PVDF film under strain into the gate of the organic thin film transistors (OFET) using an arrangement that allows the full piezoelectric voltage to couple to the channel, while also increasing the charge retention time. A bipolar detector is created by using a UV-Ozone treatment to shift the threshold voltage and increase the current of the transistor under both compressive and tensile strain. An array of strain sensors which maps the strain field on a PVDF film surface is demonstrated in this work. The strain sensor experience inspires a tone analyzer built using distributed resonator architecture on a tensioned piezoelectric PVDF sheet. This sheet is used as both the resonator and detection element. Two architectures are demonstrated; one uses distributed directly addressed elements as a proof of concept, and the other integrates organic thin film transistor-based transimpedance amplifiers monolithically with the PVDF sheet to convert the piezoelectric charge signal into a current signal for future applications such as sound field imaging. The PVDF sheet material is instrumented along its length and the amplitude response at 15 sites is recorded and analyzed as a function of the frequency of excitation. The determination of the dominant frequency component of an incoming sound is demonstrated using linear system decomposition of the time-averaged response of the sheet using no time domain detection. Our design allows for the determination of the spectral composition of a sound using the mechanical signal processing provided by the amplitude response and eliminates the need for time-domain electronic signal processing of the incoming signal. The concepts of the PVDF strain sensor and the tone analyzer trigger the idea of an active matrix microphone through the integration of organic thin film transistors with a freestanding piezoelectric polymer sheet. Localized acoustic pressure detection is enabled by switch transistors and local transimpedance amplification built into the active matrix architecture. The frequency of detection ranges from DC to 15KHz; the bandwidth is extended using an architecture that provides for virtually zero gate/source and gate/drain capacitance at the sensing transistors and low overlap capacitance at the switch transistors. A series of measurements are taken to demonstrate localized

Hsu, Yu-Jen

380

Bipolar Disorder in Children and Teens  

MedlinePLUS

Order a free hardcopy En Español Does your child go through intense mood changes? Does your child ... a lifetime. How is bipolar disorder different in children and teens than it is in adults? When ...

381

White matter microstructure alterations in bipolar disorder  

PubMed Central

Summary Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity. PMID:22687164

Bellani, Marcella; Perlini, Cinzia; Ferro, Adele; Cerruti, Stefania; Rambaldelli, Gianluca; Isola, Miriam; Cerini, Roberto; Dusi, Nicola; Andreone, Nicola; Balestrieri, Matteo; Mucelli, Roberto Pozzi; Tansella, Michele; Brambilla, Paolo

2012-01-01

382

White matter microstructure alterations in bipolar disorder.  

PubMed

Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity. PMID:22687164

Bellani, Marcella; Perlini, Cinzia; Ferro, Adele; Cerruti, Stefania; Rambaldelli, Gianluca; Isola, Miriam; Cerini, Roberto; Dusi, Nicola; Andreone, Nicola; Balestrieri, Matteo; Pozzi Mucelli, Roberto; Tansella, Michele; Brambilla, Paolo

2012-01-01

383

Gene environment interactions in bipolar disorder.  

PubMed

It has been estimated that the heritable component of bipolar disorder ranges between 80 and 90%. However, even genome-wide association studies explain only a fraction of phenotypic variability not resolving the problem of "lost heritability". Although direct evidence for epigenetic dysfunction in bipolar disorder is still limited, methodological technologies in epigenomic profiling have advanced, offering even single cell analysing and resolving the problem of cell heterogeneity in epigenetics research. Gene overlapping with other mental disorders represents another problem in identifying potential susceptibility genes in bipolar disorder. Better understanding of the interplay between multiple environmental and genetic factors involved in the patogenesis of bipolar disorder could provide relevant information for treatment of patients with this complex disorder. Future studies on the role of these factors in psychopathological conditions, subphenotypes and endophenotypes may greatly benefit by using more precise clinical data and a combined approach with multiple research tools incorporated into a single study. PMID:21894111

Pregelj, Peter

2011-09-01

384

LEC GaAs for integrated circuit applications  

NASA Technical Reports Server (NTRS)

Recent developments in liquid encapsulated Czochralski techniques for the growth of semiinsulating GaAs for integrated circuit applications have resulted in significant improvements in the quality and quantity of GaAs material suitable for device processing. The emergence of high performance GaAs integrated circuit technologies has accelerated the demand for high quality, large diameter semiinsulating GaAs substrates. The new device technologies, including digital integrated circuits, monolithic microwave integrated circuits and charge coupled devices have largely adopted direct ion implantation for the formation of doped layers. Ion implantation lends itself to good uniformity and reproducibility, high yield and low cost; however, this technique also places stringent demands on the quality of the semiinsulating GaAs substrates. Although significant progress was made in developing a viable planar ion implantation technology, the variability and poor quality of GaAs substrates have hindered progress in process development.

Kirkpatrick, C. G.; Chen, R. T.; Homes, D. E.; Asbeck, P. M.; Elliott, K. R.; Fairman, R. D.; Oliver, J. D.

1984-01-01

385

Morphological and Electrical Characterization of GaAs Nanowires  

NASA Astrophysics Data System (ADS)

GaAs nanowires were grown using metal organic chemical vapor deposition (MOCVD) system at low pressure reactor chamber. The growth follows the vapor-liquid solid mechanism by applying nanoparticle gold colloid on the (111)B GaAs substrate. The growth process were done at temperatures ranging from 380 to 600° C. The prepared samples were characterized using scanning electron microscopy, SEM and conductive atomic force microscopy, CAFM. It shows that GaAs nanowires grown at lower temperatures were rod-shaped and increasingly tapered with increasing growth temperature. Electrical measurements on individual GaAs nanowires indicate ohmic characteristic for samples prepared at 440° C, while oscillation current occured for GaAs nanowire with higher growth temperatures. These properties of GaAs nanowires can be guided to provide an opportunity for direct integration of high performance III-V semiconductor nanoscale devices.

Muhammad, Rosnita; Othaman, Zulkafli; Wahab, Yussof; Sakrani, Samsudi

2009-07-01

386

GaAs shallow-homojunction solar cells  

NASA Astrophysics Data System (ADS)

The feasibility of fabricating space resistant, high efficiency, light weight, low cost GaAs shallow homojunction solar cells for space application is investigated. The material preparation of ultrathin GaAs single crystal layers, and the fabrication of efficient GaAs solar cells on bulk GaAs substrates are discussed. Considerable progress was made in both areas, and conversion efficiency about 16% AMO was obtained using anodic oxide as a single layer antireflection coating. A computer design shows that even better cells can be obtained with double layer antireflection coating. Ultrathin, high efficiency solar cells were obtained from GaAs films prepared by the CLEFT process, with conversion efficiency as high as 17% at AMI from a 10 micrometers thick GaAs film. A organometallic CVD was designed and constructed.

Fan, J. C. C.

1981-06-01

387

Surface roughness exacerbated performance degradation in silicon nanowire transistors  

E-print Network

Surface roughness exacerbated performance degradation in silicon nanowire transistors D. Basu,a M over the channel region. Of the alternative devices being researched, silicon nanowire transistors. There- fore, several new devices such as carbon nanotube field- effect transistors, double

Gilbert, Matthew

388

Logic synthesis for pass-transistor design  

Microsoft Academic Search

New logic CMOS families using pass-transistor circuit techniques have recently been proposed with the objective of improving speed and power consumption. The double pass-transistor logic, developed by Hitachi in 1993 has proven that in 0.25 ?m CMOS technology, DPL full adder is as fast as that of CPL. In this work, a method for synthesis of pass-transistor logic has been

V. G. Oklobdzija; B. Duchene

1995-01-01

389

Fracture of GaAs Wafers  

Microsoft Academic Search

Fracture characteristics of undoped and several kinds of doped GaAs single-crystal wafers were studied. The fracture toughness value determined by four-point bending fracture test of specimens precracked by indentation at room temperature showed no difference for In-, Si-, Cr- and undoped crystals. Indentation microcracking characteristics of In-, Si- and undoped crystals and probability distribution functions of the fracture stresses of

Kiyoshi Yasutake; Yoshito Konishi; Kaoru Adachi; Kumayasu Yoshii; Masataka Umeno; Hideaki Kawabe

1988-01-01

390

Piezoelectric field in strained GaAs.  

SciTech Connect

This report describes an investigation of the piezoelectric field in strained bulk GaAs. The bound charge distribution is calculated and suitable electrode configurations are proposed for (1) uniaxial and (2) biaxial strain. The screening of the piezoelectric field is studied for different impurity concentrations and sample lengths. Electric current due to the piezoelectric field is calculated for the cases of (1) fixed strain and (2) strain varying in time at a constant rate.

Chow, Weng Wah; Wieczorek, Sebastian Maciej

2005-11-01

391

Crystal growth of device quality GaAs in space  

NASA Technical Reports Server (NTRS)

The crystal growth, device processing and device related properties and phenomena of GaAs are investigated. Our GaAs research evolves about these key thrust areas. The overall program combines: (1) studies of crystal growth on novel approaches to engineering of semiconductor materials (i.e., GaAs and related compounds); (2) investigation and correlation of materials properties and electronic characteristics on a macro- and microscale; (3) investigation of electronic properties and phenomena controlling device applications and device performance. The ground based program is developed which would insure successful experimentation with and eventually processing of GaAs in a near zero gravity environment.

Gatos, H. C.; Lagowski, J.

1984-01-01

392

High efficiency, low cost thin GaAs solar cells  

NASA Astrophysics Data System (ADS)

The feasibility of fabricating space-resistant, high efficiency, light-weight, low-cost GaAs shallow-homojunction solar cells for space application is demonstrated. This program addressed the optimal preparation of ultrathin GaAs single-crystal layers by AsCl3-GaAs-H2 and OMCVD process. Considerable progress has been made in both areas. Detailed studies on the AsCl3 process showed high-quality GaAs thin layers can be routinely grown. Later overgrowth of GaAs by OMCVD has been also observed and thin FaAs films were obtained from this process.

Fan, J. C. C.

1982-09-01

393

Improving Silicon Carbide Transistor Performance  

E-print Network

the electron mobility at the SiO2 /SiC interfaces. R E F E R E N C E Relationship between 4H-SiC/SiO2 (Auburn University) G O A L To improve electron mobility at the SiO2 /SiC interfaces in high power, high temperature SiC-based metal­oxide­semiconductor field-effect transistor (MOSFET) devices by decreasing

394

A single-atom transistor  

NASA Astrophysics Data System (ADS)

The ability to control matter at the atomic scale and build devices with atomic precision is central to nanotechnology. The scanning tunnelling microscope can manipulate individual atoms and molecules on surfaces, but the manipulation of silicon to make atomic-scale logic circuits has been hampered by the covalent nature of its bonds. Resist-based strategies have allowed the formation of atomic-scale structures on silicon surfaces, but the fabrication of working devices--such as transistors with extremely short gate lengths, spin-based quantum computers and solitary dopant optoelectronic devices--requires the ability to position individual atoms in a silicon crystal with atomic precision. Here, we use a combination of scanning tunnelling microscopy and hydrogen-resist lithography to demonstrate a single-atom transistor in which an individual phosphorus dopant atom has been deterministically placed within an epitaxial silicon device architecture with a spatial accuracy of one lattice site. The transistor operates at liquid helium temperatures, and millikelvin electron transport measurements confirm the presence of discrete quantum levels in the energy spectrum of the phosphorus atom. We find a charging energy that is close to the bulk value, previously only observed by optical spectroscopy.

Fuechsle, Martin; Miwa, Jill A.; Mahapatra, Suddhasatta; Ryu, Hoon; Lee, Sunhee; Warschkow, Oliver; Hollenberg, Lloyd C. L.; Klimeck, Gerhard; Simmons, Michelle Y.

2012-04-01

395

A single-atom transistor.  

PubMed

The ability to control matter at the atomic scale and build devices with atomic precision is central to nanotechnology. The scanning tunnelling microscope can manipulate individual atoms and molecules on surfaces, but the manipulation of silicon to make atomic-scale logic circuits has been hampered by the covalent nature of its bonds. Resist-based strategies have allowed the formation of atomic-scale structures on silicon surfaces, but the fabrication of working devices-such as transistors with extremely short gate lengths, spin-based quantum computers and solitary dopant optoelectronic devices-requires the ability to position individual atoms in a silicon crystal with atomic precision. Here, we use a combination of scanning tunnelling microscopy and hydrogen-resist lithography to demonstrate a single-atom transistor in which an individual phosphorus dopant atom has been deterministically placed within an epitaxial silicon device architecture with a spatial accuracy of one lattice site. The transistor operates at liquid helium temperatures, and millikelvin electron transport measurements confirm the presence of discrete quantum levels in the energy spectrum of the phosphorus atom. We find a charging energy that is close to the bulk value, previously only observed by optical spectroscopy. PMID:22343383

Fuechsle, Martin; Miwa, Jill A; Mahapatra, Suddhasatta; Ryu, Hoon; Lee, Sunhee; Warschkow, Oliver; Hollenberg, Lloyd C L; Klimeck, Gerhard; Simmons, Michelle Y

2012-04-01

396

Treatment Guidelines for Children and Adolescents With Bipolar Disorder: Child Psychiatric Workgroup on Bipolar Disorder  

Microsoft Academic Search

Clinicians who treat children and adolescents with bipolar disorder desperately need current treatment guidelines. These guidelines were developed by expert consensus and a review of the extant literature about the diagnosis and treatment of pediatric bipolar disorders. The four sections of these guidelines include diagnosis, comorbidity, acute treatment, and main- tenance treatment. These guidelines are not intended to serve as

ROBERT A. KOWATCH; MARY FRISTAD; BORIS BIRMAHER; KAREN DINEEN WAGNER; ROBERT L. FINDLING; MARTHA HELLANDER

397

The International Society for Bipolar Disorders (ISBD) Task Force Report on Antidepressant Use in Bipolar Disorders  

PubMed Central

Objective The risk-benefit profile of antidepressant medications in bipolar disorder is controversial. When conclusive evidence is lacking, expert consensus can guide treatment decisions. The International Society for Bipolar Disorders (ISBD) convened a task force to seek consensus recommendations on the use of antidepressants in bipolar disorders. Method An expert task force iteratively developed consensus through serial consensus-based revisions using the Delphi method. Initial survey items were based on systematic review of the literature. Subsequent surveys included new or reworded items and items that needed to be rerated. This process resulted in the final ISBD Task Force clinical recommendations on antidepressant use in bipolar disorder. Results There is striking incongruity between the wide use of and the weak evidence base for the efficacy and safety of antidepressant drugs in bipolar disorder. Few well-designed, long-term trials of prophylactic benefits have been conducted, and there is insufficient evidence for treatment benefits with antidepressants combined with mood stabilizers. A major concern is the risk for mood switch to hypomania, mania, and mixed states. Integrating the evidence and the experience of the task force members, a consensus was reached on 12 statements on the use of antidepressants in bipolar disorder. Conclusions Because of limited data, the task force could not make broad statements endorsing antidepressant use but acknowledged that individual bipolar patients may benefit from antidepressants. Regarding safety, serotonin reuptake inhibitors and bupropion may have lower rates of manic switch than tricyclic and tetracyclic antidepressants and norepinephrine-serotonin reuptake inhibitors. The frequency and severity of antidepressant-associated mood elevations appear to be greater in bipolar I than bipolar II disorder. Hence, in bipolar I patients antidepressants should be prescribed only as an adjunct to mood-stabilizing medications. PMID:24030475

Pacchiarotti, Isabella; Bond, David J.; Baldessarini, Ross J.; Nolen, Willem A.; Grunze, Heinz; Licht, Rasmus W.; Post, Robert M.; Berk, Michael; Goodwin, Guy M.; Sachs, Gary S.; Tondo, Leonardo; Findling, Robert L.; Youngstrom, Eric A.; Tohen, Mauricio; Undurraga, Juan; Gonzalez-Pinto, Ana; Goldberg, Joseph F.; Yildiz, Aysegul; Altshuler, Lori L.; Calabrese, Joseph R.; Mitchell, Philip B.; Thase, Michael E.; Koukopoulos, Athanasios; Colom, Francesc; Frye, Mark A.; Malhi, Gin S.; Fountoulakis, Konstantinos N.; Vazquez, Gustavo; Perlis, Roy H.; Ketter, Terence A.; Cassidy, Frederick; Akiskal, Hagop; Azorin, Jean-Michel; Valenti, Marc; Mazzei, Diego Hidalgo; Lafer, Beny; Kato, Tadafumi; Mazzarini, Lorenzo; Martinez-Aran, Anabel; Parker, Gordon; Souery, Daniel; Ozerdem, Aysegul; McElroy, Susan L.; Girardi, Paolo; Bauer, Michael; Yatham, Lakshmi N.; Zarate, Carlos A.; Nierenberg, Andrew A.; Birmaher, Boris; Kanba, Shigenobu; El-Mallakh, Rif S.; Serretti, Alessandro; Rihmer, Zoltan; Young, Allan H.; Kotzalidis, Georgios D.; MacQueen, Glenda M.; Bowden, Charles L.; Ghaemi, S. Nassir; Lopez-Jaramillo, Carlos; Rybakowski, Janusz; Ha, Kyooseob; Perugi, Giulio; Kasper, Siegfried; Amsterdam, Jay D.; Hirschfeld, Robert M.; Kapczinski, Flavio; Vieta, Eduard

2014-01-01

398

Bipolar disorder and neurophysiologic mechanisms  

PubMed Central

Recent studies have suggested that some variants of bipolar disorder (BD) may be due to hyperconnectivity between orbitofrontal (OFC) and temporal pole (TP) structures in the dominant hemisphere. Some initial MRI studies noticed that there were corpus callosum abnormalities within specific regional areas and it was hypothesized that developmentally this could result in functional or effective connectivity changes within the orbitofrontal-basal ganglia-thalamocortical circuits. Recent diffusion tensor imaging (DTI) white matter fiber tractography studies may well be superior to region of interest (ROI) DTI in understanding BD. A “ventral semantic stream” has been discovered connecting the TP and OFC through the uncinate and inferior longitudinal fasciculi and the elusive TP is known to be involved in theory of mind and complex narrative understanding tasks. The OFC is involved in abstract valuation in goal and sub-goal structures and the TP may be critical in binding semantic memory with person–emotion linkages associated with narrative. BD patients have relative attenuation of performance on visuoconstructional praxis consistent with an atypical localization of cognitive functions. Multiple lines of evidence suggest that some BD alleles are being selected for which could explain the enhanced creativity in higher-ability probands. Associations between ROI’s that are not normally connected could explain the higher incidence of artistic aptitude, writing ability, and scientific achievements among some mood disorder subjects. PMID:19337455

McCrea, Simon M

2008-01-01

399

Nuclear microbeam studies of silicon-germanium heterojunction bipolar transistors (HBTs)  

NASA Astrophysics Data System (ADS)

SiGe HBTs are very attractive devices to be used in space communication applications. This technology combines the high speed of the III-V semiconductors with the well-established and easy manufacturing processes of silicon, which allows the manufacturing of RF, analog, and digital devices on the same wafer. In addition, SiGe HBTs were found to be extremely radiation hard in the context of total ionizing dose and displacement damage. However, it was shown through experiments and simulations that these devices are vulnerable to single event effects (SEEs). SEEs are changes in the normal operation of the device (its logical state, currents, transients, etc.) due to the induced currents in the electrodes by the movement of carriers created by the incident ions. We used four electrode (base, emitter, collector, and substrate) IBIC measurements at the Sandia Heavy Ion Nuclear Microprobe Facility. SiGe HBTs are usually designed using deep trench isolation (DTI) to minimize parasitic capacitances from the subcollector to the substrate (faster speed), as well as allow devices to be fabricated much closer together. It is an added bonus that the DTI does not let carriers from outside hits to diffuse into the junction and induce current. Our experiments and TCAD simulations showed that while the above goal was accomplished by this design, it increased the amount of induced charge for ion hits in the active area. Single event transients (SETs) were investigated in both standard and radiation hardened by design (RHBD) bandgap voltage reference (BGR) circuits.

Vizkelethy, G.; Phillips, S. D.; Najafizadeh, L.; Cressler, J. D.

2010-06-01

400

A heterojunction bipolar transistor with stepwise allog-graded base : analysis, design, fabrication, and characterization  

E-print Network

(cont.) features but the device self-heating turned out to be crucial for the longevity of the base micro-airbridges. The short lifetime of the base micro-airbridges was prohibitive for the realization of high frequency ...

Konistis, Konstantinos, 1973-

2004-01-01

401

Thermally induced current bifurcation in bipolar transistors L. La Spina a,*, N. Nenadovic a,1  

E-print Network

, P.O. Box 5053, 2628 CT Delft, The Netherlands b Department of Electronics and Telecommunications Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples, Italy Received 23 February 2006

Technische Universiteit Delft

402

EE 321 BJT 4 Fall 2008 Bipolar Junction Transistors, Part IV AM Radio Receiver  

E-print Network

, medium, or soft tone?) Try sine, square and triangular wave inputs. Why do they sound different? 4 the push-pull circuit and sketch its response to a 1 kHz sine wave. Do this on the right side of your proto for a sine wave input. What has happened to the cross-over distortion, and why? (Hint: look at the output

Wedeward, Kevin

403

Role of the bipolar transistor on the hot-carrier-degradation of SOI MOSFETs  

Microsoft Academic Search

Hot-carrier-induced degradation is a major challenge for shrinking further the size of bulk Si or SOI components. Although there is no evidence that the aging of SOI MOSFETs is more severe than that of bulk Si counterparts, the degradation mechanisms are more complex: (i) not only the front gate but also the buried oxide and related interface may be damaged,

Y. S. Chang; S. Cristoloveanu; G. Reichert; P. Gentil; S. S. Li; J. G. Fossum

1995-01-01

404

Substituting transistor for diode improves rectifying means  

NASA Technical Reports Server (NTRS)

Unusual transistor connection that substitutes for a silicon diode and allows significantly higher repetition rates without increasing power loss rectifies an alternating current. Operation speed is improved by a factor of 10 or more when a given diode is replaced by this transistor circuit.

Muller, R. M.

1966-01-01

405

Transparent and Flexible Carbon Nanotube Transistors  

E-print Network

Transparent and Flexible Carbon Nanotube Transistors E. Artukovic, M. Kaempgen, D. S. Hecht, S We report the fabrication of transparent and flexible transistors where both the bottom gate and the conducting channel are carbon nanotube networks of different densities and Parylene N is the gate insulator

Gruner, George

406

Development of RF transistors: a historical prospect  

Microsoft Academic Search

The development of RF transistors went almost unnoticed until the early 1980s because, unlike Si VLSI, there were no mass consumer markets for such devices. Most applications for RF transistors had been military oriented. Recently, this has been changed drastically due to the explosive growth of the markets for civil wireless communication systems. This paper covers the evolution and current

Frank Schwierz; Juin J. Liou

2001-01-01

407

A high transconductance accumulation mode electrochemical transistor.  

PubMed

An organic electrochemical transistor operates in accumulation mode with high transconductance. The channel comprises a thiophene-based conjugated polyelectrolyte, which is p-type doped by anions injected from a liquid electrolyte upon the application of a gate voltage. The use of ethylene glycol as a co-solvent dramatically improves the transconductance and the temporal response of the transistors. PMID:25312252

Inal, Sahika; Rivnay, Jonathan; Leleux, Pierre; Ferro, Marc; Ramuz, Marc; Brendel, Johannes C; Schmidt, Martina M; Thelakkat, Mukundan; Malliaras, George G

2014-11-01

408

Quantum noise minimization in transistor amplifiers  

E-print Network

General quantum restrictions on the noise performance of linear transistor amplifiers are used to identify the region in parameter space where the quantum-limited performance is achievable and to construct a practical procedure for approaching it experimentally using only the knowledge of directly measurable quantities: the gain, (differential) conductance and the output noise. A specific example of resonant barrier transistors is discussed.

U. Gavish; B. Yurke; Y. Imry

2005-05-27

409

Development of New Sealed Bipolar Lead-Acid Battery.  

National Technical Information Service (NTIS)

New light weight composite bipolar plates which can withstand the corrosive environment of the lead acid battery have made possible the construction of a sealed bipolar lead acid battery that promises to achieve very high specific power levels and substan...

A. I. Attia, J. J. Rowlette

1987-01-01

410

Bipolar pulse generator for intense pulsed ion beam accelerator  

NASA Astrophysics Data System (ADS)

A new type of pulsed ion beam accelerator named "bipolar pulse accelerator" (BPA) has been proposed in order to improve the purity of intense pulsed ion beams. To confirm the principle of the BPA, we developed a bipolar pulse generator for the bipolar pulse experiment, which consists of a Marx generator and a pulse forming line (PFL) with a rail gap switch on its end. In this article, we report the first experimental result of the bipolar pulse and evaluate the electrical characteristics of the bipolar pulse generator. When the bipolar pulse generator was operated at 70% of the full charge condition of the PFL, the bipolar pulse with the first (-138kV, 72ns) and the second pulse (+130kV, 70ns) was successfully obtained. The evaluation of the electrical characteristics indicates that the developed generator can produce the bipolar pulse with fast rise time and sharp reversing time.

Ito, H.; Igawa, K.; Kitamura, I.; Masugata, K.

2007-01-01

411

Thermoelectric Effects in Bipolar Devices: Internally Cooled Semiconductor Lasers  

E-print Network

Thermoelectric Effects in Bipolar Devices: Internally Cooled Semiconductor Lasers Kevin P. Pipe likewise neglected several microscopic heat exchange processes such as thermoelectric effects that occur to thermoelectric effects. Transport in semiconductor lasers is distinguished by its bipolar nature. Current

412

Cardiovascular Morbidity and Mortality in Bipolar Disorder  

PubMed Central

Background There has been considerable interest in the elevated risk of cardiovascular disease associated with serious mental illness. While the contemporary literature has paid much attention to major depression and schizophrenia, there has been more limited focus on the risk of cardiovascular mortality for those suffering from bipolar disorder, despite some interest in the historical literature. Methods We reviewed the historical and contemporary literature related to cardiovascular morbidity and mortality in bipolar disorder. Results In studies that specifically assess cardiovascular mortality, bipolar disorder has been associated with a near doubling of risk when compared to general population estimates. This may be explained by the elevated burden of cardiovascular risk factors found in this population. These findings pre-date modern treatments, which may further influence cardiovascular risk. Conclusions Given the substantial risk of cardiovascular disease, rigorous assessment of cardiovascular risk is warranted for patients with bipolar disorder. Modifiable risk factors should be treated when identified. Further work is warranted to study mechanisms by which this elevated risk for cardiovascular disease are mediated and to identify systems for effective delivery of integrated medical and psychiatric care for individuals with bipolar disorder. PMID:21318195

Weiner, Miriam; Warren, Lois; Fiedorowicz, Jess G.

2011-01-01

413

Fundamentals of bipolar high-frequency surgery.  

PubMed

In endoscopic surgery a very precise surgical dissection technique and an efficient hemostasis are of decisive importance. The bipolar technique may be regarded as a method which satisfies both requirements, especially regarding a high safety standard in application. In this context the biophysical and technical fundamentals of this method, which have been known in principle for a long time, are described with regard to the special demands of a newly developed field of modern surgery. After classification of this method into a general and a quasi-bipolar mode, various technological solutions of specific bipolar probes, in a strict and in a generalized sense, are characterized in terms of indication. Experimental results obtained with different bipolar instruments and probes are given. The application of modern microprocessor-controlled high-frequency surgery equipment and, wherever necessary, the integration of additional ancillary technology into the specialized bipolar instruments may result in most useful and efficient tools of a key technology in endoscopic surgery. PMID:8055306

Reidenbach, H D

1993-04-01

414

A 'sticky' interhemispheric switch in bipolar disorder?  

PubMed Central

Despite years of research into bipolar disorder (manic depression), its underlying pathophysiology remains elusive. It is widely acknowledged that the disorder is strongly heritable, but the genetics are complex with less than full concordance in monozygotic twins and at least four susceptibility loci identified. We propose that bipolar disorder is the result of a genetic propensity for slow interhemispheric switching mechanisms that become 'stuck' in one or the other state. Because slow switches are also 'sticky' when compared with fast switches, the clinical manifestations of bipolar disorder may be explained by hemispheric activation being 'stuck' on the left (mania) or on the right (depression). Support for this 'sticky' interhemispheric switching hypothesis stems from our recent observation that the rate of perceptual alternation in binocular rivalry is slow in euthymic subjects with bipolar disorder (n = 18, median = 0.27 Hz) compared with normal controls (n = 49, median = 0.60 Hz, p < 0.0005). We have presented evidence elsewhere that binocular rivalry is itself an interhemispheric switching phenomenon. The rivalry alternation rate (putative interhemispheric switch rate) is robust in a given individual, with a test-retest correlation of more than 0.8, making it suitable for genetic studies. The interhemispheric switch rate may provide a trait-dependent biological marker for bipolar disorder. PMID:9872002

Pettigrew, J D; Miller, S M

1998-01-01

415

Panel fabrication utilizing GaAs solar cells  

NASA Technical Reports Server (NTRS)

The development of the GaAs solar cells for space applications is described. The activities in the fabrication of GaAs solar panels are outlined. Panels were fabricated while introducing improved quality control, soldering laydown and testing procedures. These panels include LIPS II, San Marco Satellite, and a low concentration panel for Rockwells' evaluation. The panels and their present status are discussed.

Mardesich, N.

1984-01-01

416

Theory of mind deficits in bipolar affective disorder  

Microsoft Academic Search

Background: Bipolar affective disorder patients often show cognitive deficits that are similar to those found in schizophrenia patients. Theory of mind (the ability to understand others’ mental states) is compromised in currently ill schizophrenia patients. This study aimed to establish whether similar deficits are found in bipolar patients. Methods: We measured theory of mind ability in 20 bipolar-manic patients, 15

Natalie Kerr; Robin I. M Dunbar; Richard P Bentall

2003-01-01

417

CASE REPORT Open Access A bipolar disorder patient becoming  

E-print Network

CASE REPORT Open Access A bipolar disorder patient becoming asymptomatic after adjunctive anti be involved in bipolar disorder. So far, few have been written for the association between parasitic infection and bipolar disorder. Filariasis is a parasitic disease acting ruthlessly via mosquitos and affecting more

Paris-Sud XI, Université de

418

IMMEDIATE COMMUNICATION Whole-genome association study of bipolar disorder  

E-print Network

IMMEDIATE COMMUNICATION Whole-genome association study of bipolar disorder P Sklar1,2,3,4 , JW, London, UK We performed a genome-wide association scan in 1461 patients with bipolar (BP) 1 disorder, 2008 controls drawn from the Systematic Treatment Enhancement Program for Bipolar Disorder

de Bakker, Paul

419

Bipolar disorder and mechanisms of action of mood stabilizers  

Microsoft Academic Search

Bipolar disorder (BD) is a major medical and social burden, whose cause, pathophysiology and treatment are not agreed on. It is characterized by recurrent periods of mania and depression (Bipolar I) or of hypomania and depression (Bipolar II). Its inheritance is polygenic, with evidence of a neurotransmission imbalance and disease progression. Patients often take multiple agents concurrently, with incomplete therapeutic

Stanley I. Rapoport; Mireille Basselin; Hyung-Wook Kim; Jagadeesh S. Rao

2009-01-01

420

Evolutionary origin of bipolar disorder-revised: EOBD-R  

Microsoft Academic Search

The hypothesis of the evolutionary origin of bipolar disorder (EOBD) synthesized ideas about the biological clock and seasonal shifts in mood (Rosenthal, Wehr) with theorizing that bipolar disorder descends from a pyknic (compact, cold-adapted) group (Kretchmer). The hypothesis suggested that bipolar behaviors evolved in the northern temperate zone as highly derived adaptations to the selective pressures of severe climatic conditions

Julia A. Sherman

421

Drug abuse and bipolar disorder: comorbidity or misdiagnosis?  

Microsoft Academic Search

Bipolar disorder is a common, severe and cyclic psychiatric illness. A strong association between alcohol dependence and bipolar disorder has been reported in numerous studies. The abuse of other drugs including cocaine, amphetamines, opiates, cannabis, and prescription medications in bipolar patients is also an important public health concern and has been less extensively investigated. This review examines the abuse of

E Sherwood Brown; Trisha Suppes; Bryon Adinoff; Nancy Rajan Thomas

2001-01-01

422

Neurocognitive and Neuroimaging Predictors of Clinical Outcome in Bipolar Disorder  

E-print Network

bipolar disorder were assessed with neuropsycholog- ical tests, symptombipolar disorder respond well to treatments designed to reduce affective and psychotic symptoms,bipolar disorder consistently find that during periods of symptomatic recovery, bipolar individuals often continue to experience residual mood symptoms

Bearden, Carrie E.; Woogen, Michelle; Glahn, David C.

2010-01-01

423

Maintenance Efficacy of Divalproex in the Prevention of Bipolar Depression  

Microsoft Academic Search

Breakthrough depression is a common problem in the treatment of bipolar disorder. Only one, recently published, double-blind, placebo-controlled trial has examined the efficacy of divalproex in the prevention of depressive episodes in bipolar patients. This report describes, in further detail, the findings from that trial of the effect of divalproex on multiple dimensions of depressive morbidity in bipolar disorder. A

Laszlo Gyulai; Charles L Bowden; Susan L McElroy; Joseph R Calabrese; Frederick Petty; Alan C Swann; James C-Y Chou; Adel Wassef; Craig S Risch; Robert M A Hirschfeld; Charles B Nemeroff; Paul E Keck; Dwight L Evans; Patricia J Wozniak

2003-01-01

424

REVIEW Open Access European Network of Bipolar Research Expert  

E-print Network

REVIEW Open Access European Network of Bipolar Research Expert Centre (ENBREC): a network to foster Kessing11 , Jan Scott12 , Michael Bauer13 and The ENBREC study group14 Abstract Bipolar disorders rank of Bipolar Research Expert Centres (ENBREC) designed specifically to facilitate EU-wide studies. ENBREC

Boyer, Edmond

425

Pharmacotherapy of depression and mixed states in bipolar disorder  

Microsoft Academic Search

The treatment of bipolar depression requires the resolution of depression and the establishment of mood stability. A basic problem is that the treatments used in treating bipolar depression were developed and proven effective for other disease states: antidepressants for unipolar depression, and mood stabilizers for mania. The panel addressed four unresolved questions regarding depression in relation to bipolar disorder: (1)

Stuart A Montgomery; Alan F Schatzberg; J. D Guelfi; Siegfried Kasper; Charles Nemeroff; Alan Swann; John Zajecka

2000-01-01

426

Bipolar II versus unipolar chronic depression: A 312-case study  

Microsoft Academic Search

Differences between bipolar II depression and unipolar depression have been reported, such as a lower age at onset and more atypical features in bipolar II depression. The aim of the present study was to compare chronic\\/nonchronic bipolar II depression with chronic\\/nonchronic unipolar depression to determine whether the reported differences are present when chronicity is taken into account. Three hundred twelve

Franco Benazzi

1999-01-01

427

Development of bipolar lead acid batteries with cladded materials  

Microsoft Academic Search

In work carried out at Trojan Battery Company, cladded lead and nonlead metals were used to form electrodes for incorporation into a bipolar battery design. A bipolar battery construction offers advantages in power capability due to low internal resistance, high specific energy due to the removal of passive lead parts and more efficient battery assembly through simplified construction. A bipolar

J. A. Wertz

2001-01-01

428

Family Environment and Suicidal Ideation Among Bipolar Youth  

Microsoft Academic Search

The objective of this study was to examine the association between family environment and suicidal ideation among youth with bipolar disorder. Subjects included 446 bipolar (BP) youth (age 7–17) enrolled in the Course and Outcome of Bipolar Youth study. Current suicidal ideation, family functioning and family stress were assessed at intake. BP youth with current suicidal ideation reported more conflict

Tina R. Goldstein; Boris Birmaher; David Axelson; Benjamin I. Goldstein; Mary Kay Gill; Christianne Esposito-Smythers; Neal D. Ryan; Michael A. Strober; Jeffrey Hunt; Martin Keller

2009-01-01

429

[Annual costs of bipolar disorders in Germany].  

PubMed

With costs of approximately 5.8 billion EUR annually, bipolar disorders represent a substantial burden on German society. The costs are mainly due to high indirect costs caused by morbidity-related unemployment, suicide-related losses of productivity, time off from work, and early retirement. Inpatient care, with a considerable average length of stay for patients with bipolar disorders, accounts for two-thirds of direct costs. This paper refers to statistics on use of healthcare services based primarily on the International Statistical Classification of Diseases, Tenth Revision. Representing a relatively narrow definition of bipolar disorders in comparison with the clinically relevant spectrum, this classification leads to a conservative estimate of the total costs. The significant lag between first acute episode and a correct diagnosis causes a delayed onset of maintenance treatment that leads to increased costs. Increasing public awareness, destigmatizing the disease, and educating physicians are necessary steps to limit the substantial economic burden for society. PMID:14999464

Runge, C; Grunze, H

2004-09-01

430

Multicore Processor Cluster Based Sleep Transistor Sizing Considering Delay Profile  

E-print Network

Multicore Processor Cluster Based Sleep Transistor Sizing Considering Delay Profile Huang Huang, Jeffrey Fan* Abstract-- This paper proposed a novel method to size the sleep transistor by considering and the total size of sleep transistors can be dramatically reduced. In theory, the size of sleep transistor can

Fan, Jeffrey

431

CMOS Transistor Mismatch Model valid from Weak to Strong Inversion  

E-print Network

CMOS Transistor Mismatch Model valid from Weak to Strong Inversion Teresa Serrano and PMOS transistors for 30 different geometries has been done with this continuos model. The model is able of transistor mismatch is crucial for precision analog design. Using very reduced transistor geometries produces

Barranco, Bernabe Linares

432

Page 1 of 5 Using transistors as switches  

E-print Network

Page 1 of 5 Using transistors as switches by Dan Morris Intro A key aspect of proper hacking is the use of transistors for switching things on and off. A typical example is using a computer's parallel at the silicon level in a transistor. So every time I used a transistor circuit in a project, I would promptly

Salisbury, Kenneth

433

Sleep Transistor Sizing and Control for Resonant Supply  

E-print Network

1 Sleep Transistor Sizing and Control for Resonant Supply Noise Damping Jie Gu, Hanyong Eom@ece.umn.edu www.umn.edu/~chriskim/ #12;2 Outline · Introduction · Conventional Sizing of Sleep Transistors · Sleep Transistor Sizing Considering Resonant Supply Damping · Adaptive Sleep Transistor Circuit · Conclusions #12

Kim, Chris H.

434

Bipolar outflows and the evolution of stars  

NASA Astrophysics Data System (ADS)

Hypersonic bipolar outflows are a ubiquitous phenomena associated with both young and highly evolved stars. Observations of Planetary Nebulae, the nebulae surrounding Luminous Blue Variables such as ? Carinae, Wolf Rayet bubbles, the circumstellar environment of SN 1987A and Young Stellar Objects all reveal high velocity outflows with a wide range of shapes. In this paper the current state of our theoretical understanding of these outflows is reviewed. Beginning with Planetary Nebulae considerable progress has been made in understanding bipolar outflows as the result of stellar winds interacting with the circumstellar environment. In what has been called the "Generalized Wind Blown Bubble" (GWBB) scenario, a fast tenuous wind from the central star expands into a ambient medium with an aspherical (toroidal) density distribution. Inertial gradients due to the gaseous torus quickly lead to an expanding prolate or bipolar shell of swept-up gas bounded by strong shock waves. Numerical simulations of the GWBB scenario show a surprisingly rich variety of gasdynamical behavior, allowing models to recover many of the observed properties of stellar bipolar outflows including the development of collimated supersonic jets. In this paper the physics behind the GWBB scenario is reviewed in detail and its strengths and weakness are considered. Alternative models involving MHD processes are also examined. Applications of these models to each of the principle classes of stellar bipolar outflow (YSO, PNe, LBV, SN87A) are then reviewed. Outstanding issues in the study of bipolar outflows are considered as are those questions which arise when the outflows are viewed as a single class of phenomena occurring across the HR diagram.

Frank, Adam

1999-05-01

435

Bipolar Outflows and the Evolution of Stars  

E-print Network

Hypersonic bipolar outflows are a ubiquitous phenomena associated with both young and highly evolved stars. Observations of Planetary Nebulae, the nebulae surrounding Luminous Blue Variables such as $\\eta$ Carinae, Wolf Rayet bubbles, the circumstellar environment of SN 1987A and Young Stellar Objects all revealed high velocity outflows with a wide range of shapes. In this paper I review the current state of our theoretical understanding of these outflows. Beginning with Planetary Nebulae considerable progress has been made in understanding bipolar outflows as the result of stellar winds interacting with the circumstellar environment. In what has been called the "Generalized Wind Blown Bubble" (GWBB) scenario, a fast tenuous wind from the central star expands into a ambient medium with an aspherical (toroidal) density distribution. Inertial gradients due to the gaseous torus quickly lead to an expanding prolate or bipolar shell of swept-up gas bounded by strong shock waves. Numerical simulations of the GWBB scenario show a surprisingly rich variety of gasdynamical behavior, allowing models to recover many of the observed properties of stellar bipolar outflows including the development of collimated supersonic jets. In this paper we review the physics behind the GWBB scenario in detail and consider its strengths and weakness. Alternative models involving MHD processes are also examined. Applications of these models to each of the principle classes of stellar bipolar outflow (YSO, PNe, LBV, SN87A) are then reviewed. Outstanding issues in the study of bipolar outflows are considered as are those questions which arise when the outflows are viewed as a single class of phenomena occuring across the HR diagram.

Adam Frank

1998-05-20

436

Au impact on GaAs epitaxial growth on GaAs (111){sub B} substrates in molecular beam epitaxy  

SciTech Connect

GaAs growth behaviour under the presence of Au nanoparticles on GaAs {l_brace}111{r_brace}{sub B} substrate is investigated using electron microscopy. It has been found that, during annealing, enhanced Ga surface diffusion towards Au nanoparticles leads to the GaAs epitaxial growth into {l_brace}113{r_brace}{sub B} faceted triangular pyramids under Au nanoparticles, governed by the thermodynamic growth, while during conventional GaAs growth, growth kinetics dominates, resulting in the flatted triangular pyramids at high temperature and the epitaxial nanowires growth at relatively low temperature. This study provides an insight of Au nanoparticle impact on GaAs growth, which is critical for understanding the formation mechanisms of semiconductor nanowires.

Liao, Zhi-Ming; Chen, Zhi-Gang; Xu, Hong-Yi; Guo, Ya-Nan; Sun, Wen; Zhang, Zhi; Yang, Lei [Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072 (Australia)] [Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072 (Australia); Lu, Zhen-Yu; Chen, Ping-Ping; Lu, Wei [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083 (China)] [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083 (China); Zou, Jin [Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072 (Australia) [Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072 (Australia); Centre for Microscopy and Microanalysis, The University of Queensland, St. Lucia, Queensland 4072 (Australia)

2013-02-11

437

Childhood Bipolar Disorder: A Clinical Vignette  

PubMed Central

Bipolar disorder in children and adolescents can easily be misdiagnosed, as symptom patterns overlap with other mood disorders and attention-deficit/hyperactivity disorder and commonly differ from adult presentations. A detailed description of the child's behavioral history and previous treatment response is critical to accurate diagnosis. Although studies with children are limited, a number of psychopharmaceuticals have been shown to provide therapeutic benefit. Parent/caregiver and educational support are essential components of successful treatment. This article describes an 11-year-old patient with bipolar disorder and then summarizes related treatment issues and options. PMID:16308579

Zylstra, Robert G.; DeFranco, Gina M.; McKay, Julia B.; Solomon, a. Lee

2005-01-01

438

Putative Drugs and Targets for Bipolar Disorder  

PubMed Central

Current pharmacotherapy for bipolar disorder (BPD) is generally unsatisfactory for a large number of patients. Even with adequate modern bipolar pharmacological therapies, many afflicted individuals continue to have persistent mood episode relapses, residual symptoms, functional impairment and psychosocial disability. Creating novel therapeutics for BPD is urgently needed. Promising drug targets and compounds for BPD worthy of further study involve the following systems: purinergic, dynorphin opioid neuropeptide, cholinergic (muscarinic and nicotinic), melatonin and serotonin (5-HT2C receptor), glutamatergic, hypothalamic-pituitary adrenal (HPA) axis have all been implicated. Intracellular pathways and targets worthy of further study include glycogen synthase kinase-3 protein, protein kinase C, arachidonic acid cascade. PMID:18704977

Zarate, Carlos A.; Manji, Husseini K.

2009-01-01

439

Electronic properties of GaAs, InAs and InP nanowires studied by terahertz spectroscopy.  

PubMed

We have performed a comparative study of ultrafast charge carrier dynamics in a range of III-V nanowires using optical pump-terahertz probe spectroscopy. This versatile technique allows measurement of important parameters for device applications, including carrier lifetimes, surface recombination velocities, carrier mobilities and donor doping levels. GaAs, InAs and InP nanowires of varying diameters were measured. For all samples, the electronic response was dominated by a pronounced surface plasmon mode. Of the three nanowire materials, InAs nanowires exhibited the highest electron mobilities of 6000 cm² V?¹ s?¹, which highlights their potential for high mobility applications, such as field effect transistors. InP nanowires exhibited the longest carrier lifetimes and the lowest surface recombination velocity of 170 cm s?¹. This very low surface recombination velocity makes InP nanowires suitable for applications where carrier lifetime is crucial, such as in photovoltaics. In contrast, the carrier lifetimes in GaAs nanowires were extremely short, of the order of picoseconds, due to the high surface recombination velocity, which was measured as 5.4 × 10?? cm s?¹. These findings will assist in the choice of nanowires for different applications, and identify the challenges in producing nanowires suitable for future electronic and optoelectronic devices. PMID:23619012

Joyce, Hannah J; Docherty, Callum J; Gao, Qiang; Tan, H Hoe; Jagadish, Chennupati; Lloyd-Hughes, James; Herz, Laura M; Johnston, Michael B

2013-05-31

440

Electronic properties of GaAs, InAs and InP nanowires studied by terahertz spectroscopy  

NASA Astrophysics Data System (ADS)

We have performed a comparative study of ultrafast charge carrier dynamics in a range of III-V nanowires using optical pump-terahertz probe spectroscopy. This versatile technique allows measurement of important parameters for device applications, including carrier lifetimes, surface recombination velocities, carrier mobilities and donor doping levels. GaAs, InAs and InP nanowires of varying diameters were measured. For all samples, the electronic response was dominated by a pronounced surface plasmon mode. Of the three nanowire materials, InAs nanowires exhibited the highest electron mobilities of 6000 cm2 V-1 s-1, which highlights their potential for high mobility applications, such as field effect transistors. InP nanowires exhibited the longest carrier lifetimes and the lowest surface recombination velocity of 170 cm s-1. This very low surface recombination velocity makes InP nanowires suitable for applications where carrier lifetime is crucial, such as in photovoltaics. In contrast, the carrier lifetimes in GaAs nanowires were extremely short, of the order of picoseconds, due to the high surface recombination velocity, which was measured as 5.4 × 105? cm s-1. These findings will assist in the choice of nanowires for different applications, and identify the challenges in producing nanowires suitable for future electronic and optoelectronic devices.

Joyce, Hannah J.; Docherty, Callum J.; Gao, Qiang; Tan, H. Hoe; Jagadish, Chennupati; Lloyd-Hughes, James; Herz, Laura M.; Johnston, Michael B.

2013-05-01

441

Implantation of carbon in GaAs  

SciTech Connect

Carbon implanted into GaAs and thermally annealed typically exhibits very low (<3%) electrical activity. It has been demonstrated that the electrical activity of C can be significantly enhanced by co-implantation with Ga. Improved activation may result from either additional damage of the crystal lattice or from stoichiometric changes, forcing the C atoms onto As sites. To determine the relative importance of each of these effects, I have undertaken a systematic study of carbon activation in GaAs. A range of co-implants have been used: group III (B, Ga), group V (N, P, As) and noble gases (Ar, Kr). The damage introduced to the substrate will depend on the mass of the ion implanted. The group III and group V co-implants will affect the crystal stoichiometry. The results indicate that both lattice damage and crystal stoichiometry are important for high electrical activity of C. Increasing the damage will increase the activation due to the increased number of As vacancies but maximum activation can be obtained only by a co-implant which not only damages the lattice but also forces the C to occupy an As site.

Moll, A.J.

1992-03-01

442

An excellent enzymatic lactic acid biosensor with ZnO nanowires-gated AlGaAs/GaAs high electron mobility transistor.  

PubMed

An excellent biosensor with ZnO nanowires-gated AlGaAs/GaAs high electron mobility transistor (HEMT) was used to detect lactic acid. Due to the new structure, addition of the Si-doped GaAs cap layer, the HEMT biosensor could detect a wide range of lactic acid concentrations from 0.03 nM to 300 mM. The novel biosensor exhibiting good performance along with fast response, high sensitivity, wide detection range, and long-term stability, can be integrated with a commercially available transmitter to realize lactic acid detection. PMID:22951602

Ma, Siwei; Liao, Qingliang; Liu, Hanshuo; Song, Yu; Li, Ping; Huang, Yunhua; Zhang, Yue

2012-10-21

443

Contacts shielding in nanowire field effect transistors  

NASA Astrophysics Data System (ADS)

Conductive metallic contacts can significantly affect the operation of field effect transistors fabricated starting from semiconductor nanowires deposited on a dielectric substrate. Screening effects can also lead to systematic errors in the estimates of transport parameters obtained on the basis of simple uniform capacitive models. We study the role of contacts in both back- and lateral-gate transistor geometries and provide rules of thumbs to predict screening effects in real devices. Additionally, we show how the contacts influence charge density profiles within the wire, focusing in particular on their evolution when transistors nonlinear properties are addressed.

Pitanti, Alessandro; Roddaro, Stefano; Vitiello, Miriam S.; Tredicucci, Alessandro

2012-03-01

444

Atomic quantum transistor based on swapping operation  

E-print Network

We propose an atomic quantum transistor based on exchange by virtual photons between two atomic systems through the control gate-atom. The quantum transistor is realized in two QED cavities coupled in nano-optical scheme. We have found novel effect in quantum dynamics of coupled three-node atomic system which provides control-SWAP(\\theta) processes in quantum transistor operation. New possibilities of quantum entanglement in an example of bright and dark qubit states have been demonstrated for quantum transport in the atomic chain. Potentialities of the proposed nano-optical design for quantum computing and fundamental issues of multi-atomic physics are also discussed.

Sergey A. Moiseev; Sergey N. Andrianov; Eugene S. Moiseev

2011-08-31

445

Titanium carbide bipolar plate for electrochemical devices  

DOEpatents

A corrosion resistant, electrically conductive, non-porous bipolar plate is made from titanium carbide for use in an eletrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

LaConti, Anthony B. (Lynnfield, MA); Griffith, Arthur E. (Lynn, MA); Cropley, Cecelia C. (Acton, MA); Kosek, John A. (Danvers, MA)

2000-07-04

446

The storage battery with bipolar membranes  

Microsoft Academic Search

The storage battery consists of a three-compartment electrodialysis cell with a bipolar membrane. The main characteristics of the electric energy source are evaluated when applied to the regimes of charge, discharge and self-discharge. These regimes are subjected to the experimental study to verify the theoretical predictions. The experimentally obtained values of the performance of the battery are compared with that

Emil K. Zholkovskij; Michael C. Müller; Eberhard Staude

1998-01-01

447

Behavioral Treatment of Insomnia in Bipolar Disorder  

PubMed Central

Sleep disturbance is common in bipolar disorder. Stimulus control and sleep restriction are powerful, clinically useful behavioral interventions for insomnia, typically delivered as part of cognitive-behavioral therapy for insomnia (CBT-I). Both involve short-term sleep deprivation. The potential for manic or hypomanic symptoms to emerge after sleep deprivation in bipolar disorder raises questions about the appropriateness of these methods for treating insomnia. In a series of patients with bipolar disorder who underwent behavioral treatment for insomnia, the authors found that regularizing bedtimes and rise times was often sufficient to bring about improvements in sleep. Two patients in a total group of 15 patients reported mild increases in hypomanic symptoms the week following instruction on stimulus control. Total sleep time did not change for these individuals. Two of five patients who underwent sleep restriction reported mild hypomania that was unrelated to weekly sleep duration. Sleep restriction and stimulus control appear to be safe and efficacious procedures for treating insomnia in patients with bipolar disorder. Practitioners should encourage regularity in bedtimes and rise times as a first step in treatment, and carefully monitor changes in mood and daytime sleepiness throughout the intervention. PMID:23820830

Kaplan, Katherine A.; Harvey, Allison G.

2014-01-01

448

Brazed bipolar plates for PEM fuel cells  

DOEpatents

A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprises corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant. 6 figs.

Neutzler, J.K.

1998-07-07

449

Brazed bipolar plates for PEM fuel cells  

DOEpatents

A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprising corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant.

Neutzler, Jay Kevin (Rochester, NY)

1998-01-01

450

Memory and Learning in Pediatric Bipolar Disorder.  

ERIC Educational Resources Information Center

Objective: To test the hypothesis that patients with pediatric bipolar disorder (PBPD) would demonstrate impairment relative to diagnosis-free controls of comparable age, gender, and IQ on measures of memory functioning. Method: The authors administered a battery of verbal and visuospatial memory tests to 35 outpatients with PBPD and 20 healthy…

McClure, Erin B.; Treland, Julia E.; Snow, Joseph; Dickstein, Daniel P.; Towbin, Kenneth E.; Charney, Dennis S.; Pine, Daniel S.; Leibenluft, Ellen

2005-01-01

451

Executive functioning in schizophrenic and bipolar disorder  

Microsoft Academic Search

The purpose of this study was to utilize the Wisconsin Card Sorting Test (WCST) to expand upon findings of executive dysfunction in schizophrenia and to compare schizophrenic performance to that of manics, given similarities in psychiatric symptomatology. It was hypothesized that both schizophrenic and bipolar patients would show deficient levels of executive functioning in comparison to normative data, and the

Anna Marie Stewart

1997-01-01

452

Varenicline induces manic relapse in bipolar disorder  

Microsoft Academic Search

Varenicline (Chantix) is commonly used to assist individuals with smoking cessation. This medication is known to affect mood and behavior. We report a patient with bipolar disorder who developed manic relapse after starting treatment with varenicline for tobacco dependence. Further research is necessary to establish the safety of using varenicline in individuals who have significant mental illness and want to

Natasha Knibbs; Daniel Tai-yin Tsoi

2011-01-01

453

Metallic Bipolar Plates with Composite Coatings  

E-print Network

Work Patent application filed by Argonne: "Corrosion Resistant Bipolar Plate for Polymer Electrolyte Timeline Go/No-Go decisions: ­ Sept. 30, 2010: Composite coatings that are >100 S/cm, corrosion resistant, & Testing Formal Cost Analysis Post-testing Analysis 8 -- Go/No-Go decision1 1 -- Milestone 2 3 4 7 5 6 FY09

454

Bipolar Disorder in Adolescence: Diagnosis and Treatment.  

ERIC Educational Resources Information Center

Due to developmental issues and overlapping symptoms with other disorders, diagnosing bipolar disorder in adolescents is often a confusing and complex process. This article highlights diagnostic criteria, symptoms and behaviors, and the differential diagnosis process. Treatment options are also discussed. (Contains 17 references.) (GCP)

Wilkinson, Great Buyck; Taylor, Priscilla; Holt, Jan R.

2002-01-01

455

Predominant polarity in bipolar disorder: Diagnostic implications  

Microsoft Academic Search

BackgroundIt has been reported that patients with bipolar disorder (BD) remain about 10 years symptomatic before the correct diagnosis is made. This fact is particularly important for patients with predominantly depressed polarity who tend to be diagnosed as suffering from unipolar major depressive disorder and treated with antidepressants. The present study was carried out to assess clinical differences between predominantly manic

A. R. Rosa; A. C. Andreazza; M. Kunz; F. Gomes; A. Santin; J. Sanchez-Moreno; M. Reinares; F. Colom; E. Vieta; F. Kapczinski

2008-01-01

456

Titanium Carbide Bipolar Plate for Electrochemical Devices  

SciTech Connect

Titanium carbide comprises a corrosion resistant, electrically conductive, non-porous bipolar plate for use in an electrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

LaConti, Anthony B.; Griffith, Arthur E.; Cropley, Cecelia C.; Kosek, John A.

1998-05-08

457

Compound semiconductor field-effect transistors with improved dc and high frequency performance  

SciTech Connect

A method for making compound semiconductor devices including the use of a p-type dopant is disclosed wherein the dopant is co-implanted with an n-type donor species at the time the n-channel is deposited. Also disclosed are devices manufactured using the method. In the preferred embodiment n-MESFETs and other similar field effect transistor devices are manufactured using C ions implanted with Si atoms in GaAs to form an n-channel. C exhibits a unique characteristic in the context of the invention in that it exhibits a low activation efficiency (typically, 50% or less) as a p-type dopant, and consequently, it acts to sharpen the Si n-channel by compensating Si donors in the region the Si-channel tail, but does not contribute substantially to the acceptor concentration in the region of the buried p-implant. As a result, the invention provides for improved field effect transistor devices with enhancement of both DC and high-frequency performance.

Zolper, J.C.; Sherwin, M.E.; Baca, A.G.

1995-12-31

458

Metalorganic molecular beam epitaxy growth of GaAs on patterned GaAs substrates  

NASA Astrophysics Data System (ADS)

GaAs layers were grown on etch-patterned (100) GaAs substrates by MOMBE (metalorganic molecular beam epitaxy) using TEGa (triethylgallium) and thermally cracked TEAs (triethylarsine). Morphology and orientation dependencies of the grown facets on the growth temperature (400-630°C) and V/III ratio (2-4) are investigated. Good morphology of grown layers was obtained on (111)A side facets at a low V/III ratio of 3 and low growth temperatures of 450-500°C. We also found strong evidence that the formation of facets is not only governed by the migration of Ga precursors and/or Ga atoms, but also by a preferential catalytic decomposition of Ga precursors on the facet edges.

Marx, D.; Asahi, H.; Liu, X. F.; Okuno, Y.; Inoue, K.; Gonda, S.; Shimomura, S.; Hiyamizu, S.

1994-03-01

459

Atomic hydrogen cleaning of polarized GaAs photocathodes  

SciTech Connect

Atomic hydrogen cleaning followed by heat cleaning at 450 C was used to prepare negative-electron-affinity GaAs photocathodes. When hydrogen ions were eliminated, quantum efficiencies of 15% were obtained for bulk GaAs cathodes, higher than the results obtained using conventional 600 C heat cleaning. The low-temperature cleaning technique was successfully applied to thin, strained GaAs cathodes used for producing highly polarized electrons. No depolarization was observed even when the optimum cleaning time of about 30 seconds was extended by a factor of 100.

Maruyama, Takashi

2003-04-03

460

Photocurrent Spectroscopy of Single Wurtzite GaAs Nanowires  

SciTech Connect

Photocurrent of single wurtzite GaAs nanowires grown by Au-assisted molecular beam epitaxy is measured at room and low temperature (10 K). At room temperature a high photo-response with more than two orders of magnitude increase of current is observed. The wavelength dependence of the photocurrent shows a sharp change near the zinc blende GaAs band gap. The absence of the free exciton peak in the low temperature photocurrent spectrum, and problems related to determining the exact position of the energy bandgap of wurtzite GaAs from the observed data are discussed.

Kim, D. C.; Ahtapodov, L.; Boe, A. B.; Moses, A. F.; Dheeraj, D. L.; Fimland, B. O.; Weman, H. [Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway); Choi, J. W.; Ji, H.; Kim, G. T. [School of Electrical Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

2011-12-23

461

Electrode pattern design for GaAs betavoltaic batteries  

NASA Astrophysics Data System (ADS)

The sensitivities of betavoltaic batteries and photovoltaic batteries to series and parallel resistance are studied. Based on the study, an electrode pattern design principle of GaAs betavoltaic batteries is proposed. GaAs PIN junctions with and without the proposed electrode pattern are fabricated and measured under the illumination of 63Ni. Results show that the proposed electrode can reduce the backscattering and shadowing for the beta particles from 63Ni to increase the GaAs betavoltaic battery short circuit currents effectively but has little impact on the fill factors and ideal factors.

Haiyang, Chen; Jianhua, Yin; Darang, Li

2011-08-01

462

Interstitial thermotherapy with bipolar electrosurgical devices  

NASA Astrophysics Data System (ADS)

In addition to the laser, microwave or other energy sources, interstitial thermotherapy with radio-frequency current (RFITT) in bipolar technique has already been shown in vitro to be a safe and economical alternative energy source with a comparable operating performance. The bipolar technique is, from the technical point of view, completely without risk whereas with monopolar devices, where a neutral electrode has to be applied, an uncontrolled current flow passes through the patient's body. The therapeutical application efficiency of these bipolar RF-needle applicators was evaluated using newly designed high performance flushed and cooled probes (qq 3 mm). These can be used to create large coagulation volumes in tissue such as for the palliative treatment of liver metastases or the therapy of the benign prostate hyperplasia. As a result, the achievable lesion size resulting from these flushed and internally cooled RF- probes could be increased by a factor of three compared to a standard bipolar probe. With these bipolar power RF- applicators, coagulation dimensions of 5 cm length and 4 cm diameter with a power input of 40 watt could be achieved within 20 minutes. No carbonization and electrode tissue adherence was found. Investigations in vitro with adapted RFITT-probes using paramagnetic materials such as titanium alloys and high performance plastic have shown that monitoring under MRI (Siemens Magnetom, 1.5 Tesla), allows visualization of the development of the spatial temperature distribution in tissue using an intermittent diagnostic and therapeutical application. This does not lead to a loss in performance compared to continuous application. A ratio of 1:4 (15 s Thermo Flash MRI, 60 s RF-energy) has shown to be feasible.

Desinger, Kai; Stein, Thomas; Boehme, A.; Mack, Martin G.; Mueller, Gerhard J.

1998-01-01

463

GaAs VLSI technology and circuit elements for DSP  

NASA Astrophysics Data System (ADS)

Recent progress in digital GaAs circuit performance and complexity is presented to demonstrate the current capabilities of GaAs components. High density GaAs process technology and circuit design techniques are described and critical issues for achieving favorable complexity speed power and cost tradeoffs are reviewed. Some DSP building blocks are described to provide examples of what types of DSP systems could be implemented with present GaAs technology. DIGITAL GaAs CIRCUIT CAPABILITIES In the past few years the capabilities of digital GaAs circuits have dramatically increased to the VLSI level. Major gains in circuit complexity and power-delay products have been achieved by the use of silicon-like process technologies and simple circuit topologies. The very high speed and low power consumption of digital GaAs VLSI circuits have made GaAs a desirable alternative to high performance silicon in hardware intensive high speed system applications. An example of the performance and integration complexity available with GaAs VLSI circuits is the 64x64 crosspoint switch shown in figure 1. This switch which is the most complex GaAs circuit currently available is designed on a 30 gate GaAs gate array. It operates at 200 MHz and dissipates only 8 watts of power. The reasons for increasing the level of integration of GaAs circuits are similar to the reasons for the continued increase of silicon circuit complexity. The market factors driving GaAs VLSI are system design methodology system cost power and reliability. System designers are hesitant or unwilling to go backwards to previous design techniques and lower levels of integration. A more highly integrated system in a lower performance technology can often approach the performance of a system in a higher performance technology at a lower level of integration. Higher levels of integration also lower the system component count which reduces the system cost size and power consumption while improving the system reliability. For large gate count circuits the power per gate must be minimized to prevent reliability and cooling problems. The technical factors which favor increasing GaAs circuit complexity are primarily related to reducing the speed and power penalties incurred when crossing chip boundaries. Because the internal GaAs chip logic levels are not compatible with standard silicon I/O levels input receivers and output drivers are needed to convert levels. These I/O circuits add significant delay to logic paths consume large amounts of power and use an appreciable portion of the die area. The effects of these I/O penalties can be reduced by increasing the ratio of core logic to I/O on a chip. DSP operations which have a large number of logic stages between the input and the output are ideal candidates to take advantage of the performance of GaAs digital circuits. Figure 2 is a schematic representation of the I/O penalties encountered when converting from ECL levels to GaAs

Mikkelson, James M.

1990-10-01

464

Near-field thermal transistor  

E-print Network

Using a block of three separated solid elements, a thermal source and drain together with a gate made of an insulator-metal transition material exchanging near-field thermal radiation, we introduce a nanoscale analog of a field-effect transistor which is able to control the flow of heat exchanged by evanescent thermal photons between two bodies. By changing the gate temperature around its critical value, the heat flux exchanged between the hot body (source) and the cold body (drain) can be reversibly switched, amplified, and modulated by a tiny action on the gate. Such a device could find important applications in the domain of nanoscale thermal management and it opens up new perspectives concerning the development of contactless thermal circuits intended for information processing using the photon current rather than the electric current.

Ben-Abdallah, Philippe

2013-01-01

465

Field-Effect Transistor Reactance Circuits.  

National Technical Information Service (NTIS)

Efforts to miniaturize the reactance circuits of vacuum-tube technology by using junction transistors have been only partially successful. Large equivalent inductances and capacitances are obtainable, but the effective Q is limited to low values by the lo...

G. D. Clark

1968-01-01

466

Spin effects in single-electron transistors  

E-print Network

Basic electron transport phenomena observed in single-electron transistors (SETs) are introduced, such as Coulomb-blockade diamonds, inelastic cotunneling thresholds, the spin-1/2 Kondo effect, and Fano interference. With ...

Granger, Ghislain

2005-01-01

467

Development of gallium nitride power transistors  

E-print Network

GaN-based high-voltage transistors have outstanding properties for the development of ultra-high efficiency and compact power electronics. This thesis describes a new process technology for the fabrication of GaN power ...

Piedra, Daniel, M. Eng. Massachusetts Institute of Technology

2011-01-01

468

Ballistic transport in high electron mobility transistors  

Microsoft Academic Search

A general ballistic FET model that was previously used for ballistic MOSFETs is applied to ballistic high electron mobility transistors (HEMTs), and the results are compared with experimental data for a sub-50 nm InAlAs-InGaAs HEMT. The results show that nanoscale HEMTs can be modeled as an intrinsic ballistic transistor with extrinsic source\\/drain series resistances. We also examine the \\

Jing Wang; M. Lundstrom

2003-01-01

469

Development of GaAs solar cells  

NASA Technical Reports Server (NTRS)

Calculations of GaAs solar cell output parameters were refined and a computer model was developed for parameter optimization. The results were analyzed to determine the material characteristics required for a high efficiency solar cell. Calculated efficiencies for a P/N cell polarity are higher than an N/P cell. Both cell polarities show efficiency to have a larger dependence on short circuit current than an open circuit voltage under nearly all conditions considered. The tolerances and requirements of a cell fabrication process are more critical for an N/P type than for a P/N type cell. Several solar cell fabrication considerations relative to junction formation using ion implantation are also discussed.

Mcnally, P. J.

1972-01-01

470

The Mood Disorder Questionnaire: A Simple, Patient-Rated Screening Instrument for Bipolar Disorder  

Microsoft Academic Search

Bipolar disorder is frequently encountered in primary care settings, often in the form of poor response to treatment for depression. Although lifetime prevalence of bipolar I disorder is 1%, the prevalence of bipolar spectrum disorders (e.g., bipolar I, bipolar II, and cyclothymia) is much higher, especially among patients with depression. The consequences of misdiagnosis can be devastating. One way to

Robert M. A. Hirschfeld

471

Bipolar II depression in late life: prevalence and clinical features in 525 depressed outpatients  

Microsoft Academic Search

Background: Late-life bipolar II depression has not been well studied. The aim of the present study was to find the prevalence of late-life (50 years or more) bipolar II depression among unipolar and bipolar depressed outpatients, and to compare it with bipolar II depression in younger patients, looking for differences supporting the subtyping of bipolar II depression according to age

Franco Benazzi

2001-01-01

472

Fabrication and characterization of heterojunction transistors  

NASA Astrophysics Data System (ADS)

Submircon emitter finger high-speed double heterojunction InAlAs/InGaAsSb/InGaAs bipolar transistors (DHBTs) and a variety of nitride high electron mobility transistors (HEMTs) including AlGaN/GaN, InAlN/GaN, and AlN/GaN were fabricated and characterized. DHBT structures were grown by solid source molecular beam epitaxy (SSMBE) on Fe-doped semiinsulating InP substrates and nitride HEMTs were grown with a metal organic chemical vapor deposition (MOCVD) system on sapphire or SiC substrates. AlN/GaN HEMTs were grown with a RF-VMBE on sapphire substrates. Ultra low base contact resistance of 3.7 x 10-7 ohm-cm2 after 1 min 250¢XC thermal treatment on noval InGaAsSb base of DHBTs was achieved and a long-term thermal stability of base metallization was studied. Regarding small scale DHBT fabrication, tri-layer system was introduced to improve the resolution for submicron emitter patterning and help to pile up a thicker emitter metal stack; guard-ring technique was applied around the emitter periphery in order to preserve the current gain at small emitter dimensions. Ultra low turn-on voltage and high current gain can be realized with InGaAsSb-base DHBTs as compared to the conventional InGaAs-base DHBTs. A peak current gain cutoff frequency (fT) of 268 GHz and power gain cutoff frequency (fmax) of 485 GHz were achieved. GaN-based HEMTs herein were fabricated with gate lengths from 400 nm to 1im, and were deposited Ti/Al/Ni/Au as their Ohmic contact metallization. Effects of the Ohmic contact annealing for lattice-matched InAlN/GaN HEMTs with and without a thin GaN cap layer were exhibited and their optimal annealing temperature were obtained. A maximum drain current of 1.3 A/mm and an extrinsic transconductance of 366 mS/mm were demonstrated for InAlN/GaN HEMTs with the shortest gate length. A unity-gain cutoff frequency (fT) of 69 GHz and a maximum frequency of oscillation (fmax) of 80 GHz for InAlN/GaN HEMTs were extracted from measured scattering parameters. Passivation is one of the most important parts in device processing for preventing degradation from various environmental conditions and promising a better device performance. Simply, ozone treatment of AlN on AlN/GaN heterostructures produced effective aluminum oxide surface passivation and chemical resistance to the AZ positive photoresist developer used for subsequent device fabrication. Metal oxide semiconductor diode-like gate current-voltage characteristics and minimal drain current degradation during gate pulse measurements were observed. With an additional oxygen plasma treatment on the gate area prior to the gate metal deposition, enhancement-mode AlN/GaN HEMTs were realized. In addition, for AlGaN/GaN HEMTs in high electrical field applications, a high-dielectric-strength SiNx passivation over an optimum thickness was needed to suppress surface flashover during a high voltage or high power operation. An excellent isolation blocking voltage of 900 V with a leakage current at 1 muA/mm was obtained across a nitrogen-implanted isolation-gap of 10 mum between two Ohmic pads. The radiation hardness of HBTs and HEMTs is one of the critical factors that need to be established for military, space, and nuclear industry applications. The effects of proton radiation on the dc performance of InAlAs/InGaAsSb/InGaAs HBTs and AlN/GaN HEMTs were investigated. Both of these devices showed a remarkable resistance to high energy protoninduced degradation and appeared very promising for terrestrial or space-borne applications. The proton-irradiated devices with a dose of 2 x 1011 cm-2 (estimated to be equivalent to more than 40 years of exposure in low-earth orbit) showed only small changes in dc transfer characteristics, threshold voltage shift, and gate-lag with a high frequency pulse on the gate of the HEMTs and showed small changes in junction ideality factor, generation recombination leakage current, and output conductance for the HBTs. The effect the gate metallization on the nitride HEMT reliability was also examined. By replacing the conventional Ni/Au gate metallization wi

Lo, Chien-Fong

473

GaAs monolithic RF modules for SARSAT distress beacons  

NASA Technical Reports Server (NTRS)

Monolithic GaAs UHF components for use in SARSAT Emergency Distress beacons are under development by Microwave Monolithics, Inc., Simi Valley, CA. The components include a bi-phase modulator, driver amplifier, and a 5 watt power amplifier.

Cauley, Michael A.

1991-01-01

474

Crystal growth of device quality GaAs in space  

NASA Technical Reports Server (NTRS)

GaAs device technology has recently reached a new phase of rapid advancement, made possible by the improvement of the quality of GaAs bulk crystals. At the same time, the transition to the next generation of GaAs integrated circuits and optoelectronic systems for commercial and government applications hinges on new quantum steps in three interrelated areas: crystal growth, device processing and device-related properties and phenomena. Special emphasis is placed on the establishment of quantitative relationships among crystal growth parameters-material properties-electronic properties and device applications. The overall program combines studies of crystal growth on novel approaches to engineering of semiconductor material (i.e., GaAs and related compounds); investigation and correlation of materials properties and electronic characteristics on a macro- and microscale; and investigation of electronic properties and phenomena controlling device applications and device performance.

Gatos, H. C.; Lagowski, J.

1983-01-01

475

Simulation of silicon diffusion in GaAs  

NASA Astrophysics Data System (ADS)

The simulation of coupled diffusion of silicon atoms and point defects in GaAs has been carried out for diffusion at the temperatures of 1000 and 850 °C. The amphoteric behavior of silicon atoms in GaAs has been taken into account in the investigation of high concentration diffusion from silicon layer deposited on GaAs substrate. The calculated dopant profiles agree well with the experimental ones and they confirm the adequacy of the model of silicon diffusion used for simulation. A comparison with the experimental data has enabled this work to obtain the parameters of silicon effective diffusivity and other values describing high concentration silicon diffusion in GaAs.

Saad, A. M.; Velichko, O. I.

2011-03-01

476

Spatial Modulation Of Light In GaAs  

NASA Technical Reports Server (NTRS)

Spatial modulation of light in gallium arsenide demonstrated by transferring image from one of two coherent, crossing beams of light to other one. Technique relies on cross-polarization beam coupling, product of photorefractive effect in GaAs crystal.

Cheng, Li-Jen; Gheen, Gregory; Partovi, Afshin

1989-01-01

477

GaAs Films Prepared by RF-Magnetron Sputtering  

SciTech Connect

The authors reported on the optical absorption, adhesion, and microstructure of RF-magnetron sputtered films of hydrogenated amorphous and microcrystalline GaAs films for the 1 to 25 {micro}m infrared wavelength rate. Sputtering parameters which were varied include sputtering power, temperature and pressure, and hydrogen sputtering-gas concentration. TEM results show a sharp transition from purely amorphous GaAs to a mixture of microcrystalline GaAs in an amorphous matrix at 34 {+-} 2 C. By optimizing the sputtering parameters, the optical absorption coefficient can be decreased below 100 cm{sup -1} for wavelengths greater than about 1.25 {micro}m. These results represent the lowest reported values of optical absorption for sputtered films of GaAs directly measured by spectrophotometry for the near-infrared wavelength region.

L.H. Ouyang; D.L. Rode; T. Zulkifli; B. Abraham-Shrauner; N. Lewis; M.R. Freeman

2001-08-01

478

Characteristics of GaAs with inverted thermal conversion  

NASA Technical Reports Server (NTRS)

GaAs crystals exhibiting inverted thermal conversion (ITC) of resistivity were investigated in conjunction with standard semiinsulating (SI) GaAs regarding characteristics important in device processing. It was established that dislocation density and Si implant activation are unaffected by transformation to the ITC state. However, in ITC GaAs the controlled increase of the EL2 (native midgap donor) concentration during annealing makes it possible to attain resistivities one order of magnitude greater (e.g., about 10 to the 9th ohm cm of 300 K) than those attained in standard SI GaAs (e.g., 10 to the 7th-10 to the 8th ohm cm).

Kang, C. H.; Lagowski, J.; Gatos, H. C.

1987-01-01

479

Crystal Growth of Device Quality Gaas in Space  

NASA Technical Reports Server (NTRS)

The GaAs research evolves about these key thrust areas. The overall program combines: (1) studies of crystal growth on novel approaches to engineering of semiconductor material (i.e., GaAs and related compounds); (2) investigation and correlation of materials properties and electronic characteristics on a macro- and microscale; and (3) investigation of electronic properties and phenomena controlling device applications and device performance. This effort is aimed at the essential ground-based program which would insure successful experimentation with and eventually processing of GaAs in near zero gravity environment. It is believed that this program addresses in a unique way materials engineering aspects which bear directly on the future exploitation of the potential of GaAs and related materials in device and systems applications.

Gatos, H. C.

1985-01-01

480

Thermal chondroplasty: effect of bipolar and monopolar radio frequency energy  

NASA Astrophysics Data System (ADS)

Cartilage fibrillation is commonly associated with injury and long-term degeneration. Contouring the articular surface with radiofrequency energy (RFE) may stabilize the surface, and improve clinical function, but subchondral bone injury has been reported in some patients. The purpose of this research was to document the effects of bipolar and monopolar RFE on articular cartilage. Bipolar RFE and monopolar RFE treatment of abraded bovine cartilage was investigated in an in vitro model. Bipolar RFE caused greater chondrocyte death than monopolar RFE, (bipolar RFE: 1700-mm; monopolar RFE: 800-mm) (p<0.05). Both bipolar RFE and monopolar RFE contoured the articular surface but the depth of chondrocyte death raised concerns regarding the clinical application of RFE. Further work investigated the arthroscopic application of bipolar RFE and monopolar RFE on human chondromalacic cartilage in vitro. Both devices smoothed the fibrillated surface, but bipolar RFE caused increased depth of chondrocyte death compared to monopolar RFE (bipolar RFE 2100-mm; monopolar RFE 620-mm (p<0.05). Fluoroptic thermometry has demonstrated cartilage matrix temperatures exceeding 70° C 2-mm below the articular surface during the application of bipolar RFE. The clinical use of the bipolar RFE systems available to date will likely result in unacceptable chondrocyte death and subchondral injury. While RFE demonstrates some promise for the management of cartilage injury, further work must be completed to define the parameters for its application.

Edwards, Ryland B.; Lu, Yan; Cole, Brian J.; Markel, Mark D.

2001-06-01

481

Characterisation of semi-insulating GaAs  

NASA Technical Reports Server (NTRS)

Hole and electron mobilities as functions of temperature and ionised impurity concentration are calculated for GaAs. It is shown that these calculations, when used to analyse electrical properties of semi-insulating GaAs, enable an assessment of the Fermi energy position and ionised impurity concentration to be made. In contrast to previous work, the analysis does not require any phenomenological assumptions.

Walukiewicz, W.; Pawlowicz, L.; Lagowski, J.; Gatos, H. C.

1982-01-01

482

Recovery of high field GaAs photoconductive semiconductor switches  

Microsoft Academic Search

The authors discuss the recovery of GaAs PCSS (photoconductive semiconductor switches) after they are triggered into a high gain switching mode called lock-on. Fast recovery of GaAs switches after high field switching is of particular interest for high repetition rate applications where it is difficult to provide the large optical trigger energy required for switches operating at low fields. Three

F. J. Zutavern; G. M. Loubriel; M. W. O'Malley; L. P. Schanwald; D. L. McLaughlin

1990-01-01

483

Recovery of high field GaAs photoconductive semiconductor switches  

Microsoft Academic Search

GaAs photoconductive semiconductor switches (PCSS) are useful as fast recovery switches at electric field stresses below 3.5-8 kV\\/cm. Following a short activating light pulse in this low field regime, the switch resistance increases roughly exponentially with time constants ranging from 0.1-1000 ns, depending on the type of GaAs. At higher fields, however, the resistive recovery depends not only on material

F. J. Zutavern; G. M. Loubriel; M. W. Omalley; L. P. Schanwald; D. L. McLaughlin

1990-01-01

484

Atomic Hydrogen-Assisted GaAs Molecular Beam Epitaxy  

Microsoft Academic Search

A continual irradiation of atomic H during the growth of GaAs in molecular beam epitaxy (MBE) has been shown to be a viable method to obtain sharp heterointerfaces and high-quality epitaxial layers. We provide some fundamentally important observations related to atomic scale mechanisms and interactions, and the growth models for atomic H-assisted homoepitaxial GaAs MBE are proposed. Atomic H has

Yoshitaka Okada; Takeyoshi Sugaya; Shigeru Ohta; Tomoya Fujita; Mitsuo Kawabe

1995-01-01

485

Thermal stress cycling of GaAs solar cells  

Microsoft Academic Search

A thermal cycling experiment was performed on GaAs solar cells to establish the electrical and structural integrity of these cells under the temperature conditions of a simulated low-Earth orbit of 3-year duration. Thirty single junction GaAs cells were obtained and tests were performed to establish the beginning-of-life characteristics of these cells. The tests consisted of cell I-V power output curves,

B. K. Janousek; R. W. Francis; J. P. Wendt

1985-01-01

486

Shunt effect in polycrystalline GaAs solar cells  

Microsoft Academic Search

Thin-film polycrystalline GaAs solar cells have the potential for reduced cost while retaining high efficiency. However, solar cells made from polycrystalline GaAs have historically had poor open-circuit voltages. Models that account for these low voltages suggest that in order to make solar cells with high voltages it is necessary to use material with very large grains. As an alternative cause

Christiana Honsberg; Allen M. Bernett

1990-01-01

487

Electrode pattern design for GaAs betavoltaic batteries  

Microsoft Academic Search

The sensitivities of betavoltaic batteries and photovoltaic batteries to series and parallel resistance are studied. Based on the study, an electrode pattern design principle of GaAs betavoltaic batteries is proposed. GaAs PIN junctions with and without the proposed electrode pattern are fabricated and measured under the illumination of 63Ni. Results show that the proposed electrode can reduce the backscattering and

Chen Haiyang; Yin Jianhua; Li Darang

2011-01-01

488

Laser Liftoff of GaAs Thin Films  

E-print Network

The high cost of single crystal III-V substrates limits the use of GaAs and related sphalerite III-V materials in many applications, especially photovoltaics. Separating epitaxially-grown layers from a growth substrate can reduce costs, however the current approach, which uses an acid to laterally etch an epitaxial sacrificial layer, is slow and can damage other device layers. Here, we demonstrate a new approach that is orders of magnitude faster, and that enables more freedom in the selection of other device layers. We show damage-free removal of an epitaxial single crystal GaAs film from its GaAs growth substrate using a laser that is absorbed by a smaller-band-gap, pseudomorphic layer grown between the substrate and the GaAs film. The liftoff process transfers the GaAs film to a flexible polymer substrate, and the transferred GaAs layer is indistinguishable in structural quality from its growth substrate.

Hayes, Garrett J

2014-01-01

489