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Sample records for a-igzo tft device

  1. Enhancement of a-IGZO TFT Device Performance Using a Clean Interface Process via Etch-Stopper Nano-layers.

    PubMed

    Chung, Jae-Moon; Zhang, Xiaokun; Shang, Fei; Kim, Ji-Hoon; Wang, Xiao-Lin; Liu, Shuai; Yang, Baoguo; Xiang, Yong

    2018-05-29

    To overcome the technological and economic obstacles of amorphous indium-gallium-zinc-oxide (a-IGZO)-based display backplane for industrial production, a clean etch-stopper (CL-ES) process is developed to fabricate a-IGZO-based thin film transistor (TFT) with improved uniformity and reproducibility on 8.5th generation glass substrates (2200 mm × 2500 mm). Compared with a-IGZO-based TFT with back-channel-etched (BCE) structure, a newly formed ES nano-layer (~ 100 nm) and a simultaneous etching of a-IGZO nano-layer (30 nm) and source-drain electrode layer are firstly introduced to a-IGZO-based TFT device with CL-ES structure to improve the uniformity and stability of device for large-area display. The saturation electron mobility of 8.05 cm 2 /V s and the V th uniformity of 0.72 V are realized on the a-IGZO-based TFT device with CL-ES structure. In the negative bias temperature illumination stress and positive bias thermal stress reliability testing under a ± 30 V bias for 3600 s, the measured V th shift of CL-ES-structured device significantly decreased to - 0.51 and + 1.94 V, which are much lower than that of BCE-structured device (- 3.88 V, + 5.58 V). The electrical performance of the a-IGZO-based TFT device with CL-ES structure implies that the economic transfer from a silicon-based TFT process to the metal oxide semiconductor-based process for LCD fabrication is highly feasible.

  2. Enhancement of a-IGZO TFT Device Performance Using a Clean Interface Process via Etch-Stopper Nano-layers

    NASA Astrophysics Data System (ADS)

    Chung, Jae-Moon; Zhang, Xiaokun; Shang, Fei; Kim, Ji-Hoon; Wang, Xiao-Lin; Liu, Shuai; Yang, Baoguo; Xiang, Yong

    2018-05-01

    To overcome the technological and economic obstacles of amorphous indium-gallium-zinc-oxide (a-IGZO)-based display backplane for industrial production, a clean etch-stopper (CL-ES) process is developed to fabricate a-IGZO-based thin film transistor (TFT) with improved uniformity and reproducibility on 8.5th generation glass substrates (2200 mm × 2500 mm). Compared with a-IGZO-based TFT with back-channel-etched (BCE) structure, a newly formed ES nano-layer ( 100 nm) and a simultaneous etching of a-IGZO nano-layer (30 nm) and source-drain electrode layer are firstly introduced to a-IGZO-based TFT device with CL-ES structure to improve the uniformity and stability of device for large-area display. The saturation electron mobility of 8.05 cm2/V s and the V th uniformity of 0.72 V are realized on the a-IGZO-based TFT device with CL-ES structure. In the negative bias temperature illumination stress and positive bias thermal stress reliability testing under a ± 30 V bias for 3600 s, the measured V th shift of CL-ES-structured device significantly decreased to - 0.51 and + 1.94 V, which are much lower than that of BCE-structured device (- 3.88 V, + 5.58 V). The electrical performance of the a-IGZO-based TFT device with CL-ES structure implies that the economic transfer from a silicon-based TFT process to the metal oxide semiconductor-based process for LCD fabrication is highly feasible.

  3. Mechanism of a-IGZO TFT device deterioration—illumination light wavelength and substrate temperature effects

    NASA Astrophysics Data System (ADS)

    Chen, Te-Chih; Kuo, Yue; Chang, Ting-Chang; Chen, Min-Chen; Chen, Hua-Mao

    2017-10-01

    Device characteristics changes in an a-IGZO thin film transistor under light illumination and at raised temperature have been investigated. Light exposure causes a large leakage current, which is more obvious with an increase in the illumination energy, power and the temperature. The increase in the leakage current is due to the trap assisted photon excitation process that generates electron-hole pairs and the mechanism is enhanced with the additional thermal energy. The leakage current comes from the source side because holes generated in the process drift to the source side and therefore lower the barrier height. The above mechanism has been further verified with experiments of drain bias induced shifts in the threshold voltage and the subthreshold slope.

  4. Control of O-H bonds at a-IGZO/SiO2 interface by long time thermal annealing for highly stable oxide TFT

    NASA Astrophysics Data System (ADS)

    Jeon, Jae Kwon; Um, Jae Gwang; Lee, Suhui; Jang, Jin

    2017-12-01

    We report two-step annealing, high temperature and sequent low temperature, for amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) to improve its stability and device performance. The annealing is carried out at 300 oC in N2 ambient for 1 h (1st step annealing) and then at 250 oC in vacuum for 10 h (2nd step annealing). It is found that the threshold voltage (VTH) changes from 0.4 V to -2.0 V by the 1st step annealing and to +0.6 V by 2nd step annealing. The mobility changes from 18 cm2V-1s-1 to 25 cm2V-1s-1 by 1st step and decreases to 20 cm2V-1s-1 by 2nd step annealing. The VTH shift by positive bias temperature stress (PBTS) is 3.7 V for the as-prepared TFT, and 1.7 V for the 1st step annealed TFT, and 1.3 V for the 2nd step annealed TFT. The XPS (X-ray photoelectron spectroscopy) depth analysis indicates that the reduction in O-H bonds at the top interface (SiO2/a-IGZO) by 2nd step annealing appears, which is related to the positive VTH shift and smaller VTH shift by PBTS.

  5. Role of deposition and annealing of the top gate dielectric in a-IGZO TFT-based dual-gate ion-sensitive field-effect transistors

    NASA Astrophysics Data System (ADS)

    Kumar, Narendra; Sutradhar, Moitri; Kumar, Jitendra; Panda, Siddhartha

    2017-03-01

    The deposition of the top gate dielectric in thin film transistor (TFT)-based dual-gate ion-sensitive field-effect transistors (DG ISFETs) is critical, and expected not to affect the bottom gate TFT characteristics, while providing a higher pH sensitive surface and efficient capacitive coupling between the gates. Amorphous Ta2O5, in addition to having good sensing properties, possesses a high dielectric constant of ˜25 making it well suited as the top gate dielectric in a DG ISFET by providing higher capacitive coupling (ratio of C top/C bottom) leading to higher amplification. To avoid damage of the a-IGZO channel reported to be caused by plasma exposure, deposition of Ta2O5 by e-beam evaporation followed by annealing was investigated in this work to obtain sensitivity over the Nernst limit. The deteriorated bottom gate TFT characteristics, indicated by an increase in the channel conductance, confirmed that plasma exposure is not the sole contributor to the changes. Oxygen vacancies at the Ta2O5/a-IGZO interface, which emerged during processing, increased the channel conductivity, became filled by optimum annealing in oxygen at 400 °C for 1 h, which was confirmed by an x-ray photoelectron spectroscopy depth profiling analysis. The obtained pH sensitivity of the TFT-based DG ISFET was 402 mV pH-1, which is about 6.8 times the Nernst limit (59 mV pH-1). The concept of capacitive coupling was also demonstrated by simulating an a-IGZO-based DG TFT structure. Here, the exposure of the top gate dielectric to the electrolyte without applying any top gate bias led to changes in the measured threshold voltage of the bottom gate TFT, and this obviated the requirement of a reference electrode needed in conventional ISFETs and other reported DG ISFETs. These devices, with high sensitivities and requiring low volumes (˜2 μl) of analyte solution, could be potential candidates for utilization as chemical sensors and biosensors.

  6. Dual active layer a-IGZO TFT via homogeneous conductive layer formation by photochemical H-doping

    PubMed Central

    2014-01-01

    In this study, InGaZnO (IGZO) thin film transistors (TFTs) with a dual active layer (DAL) structure are fabricated by inserting a homogeneous embedded conductive layer (HECL) in an amorphous IGZO (a-IGZO) channel with the aim of enhancing the electrical characteristics of conventional bottom-gate-structure TFTs. A highly conductive HECL (carrier concentration at 1.6 × 1013 cm-2, resistivity at 4.6 × 10-3 Ω∙cm, and Hall mobility at 14.6 cm2/Vs at room temperature) is fabricated using photochemical H-doping by irradiating UV light on an a-IGZO film. The electrical properties of the fabricated DAL TFTs are evaluated by varying the HECL length. The results reveal that carrier mobility increased proportionally with the HECL length. Further, a DAL TFT with a 60-μm-long HECL embedded in an 80-μm-long channel exhibits comprehensive and outstanding improvements in its electrical properties: a saturation mobility of 60.2 cm2/Vs, threshold voltage of 2.7 V, and subthreshold slope of 0.25 V/decade against the initial values of 19.9 cm2/Vs, 4.7 V, and 0.45 V/decade, respectively, for a TFT without HECL. This result confirms that the photochemically H-doped HECL significantly improves the electrical properties of DAL IGZO TFTs. PMID:25435832

  7. Dual active layer a-IGZO TFT via homogeneous conductive layer formation by photochemical H-doping.

    PubMed

    Jeong, Seung-Ki; Kim, Myeong-Ho; Lee, Sang-Yeon; Seo, Hyungtak; Choi, Duck-Kyun

    2014-01-01

    In this study, InGaZnO (IGZO) thin film transistors (TFTs) with a dual active layer (DAL) structure are fabricated by inserting a homogeneous embedded conductive layer (HECL) in an amorphous IGZO (a-IGZO) channel with the aim of enhancing the electrical characteristics of conventional bottom-gate-structure TFTs. A highly conductive HECL (carrier concentration at 1.6 × 10(13) cm(-2), resistivity at 4.6 × 10(-3) Ω∙cm, and Hall mobility at 14.6 cm(2)/Vs at room temperature) is fabricated using photochemical H-doping by irradiating UV light on an a-IGZO film. The electrical properties of the fabricated DAL TFTs are evaluated by varying the HECL length. The results reveal that carrier mobility increased proportionally with the HECL length. Further, a DAL TFT with a 60-μm-long HECL embedded in an 80-μm-long channel exhibits comprehensive and outstanding improvements in its electrical properties: a saturation mobility of 60.2 cm(2)/Vs, threshold voltage of 2.7 V, and subthreshold slope of 0.25 V/decade against the initial values of 19.9 cm(2)/Vs, 4.7 V, and 0.45 V/decade, respectively, for a TFT without HECL. This result confirms that the photochemically H-doped HECL significantly improves the electrical properties of DAL IGZO TFTs.

  8. Photo-Induced Room-Temperature Gas Sensing with a-IGZO Based Thin-Film Transistors Fabricated on Flexible Plastic Foil.

    PubMed

    Knobelspies, Stefan; Bierer, Benedikt; Daus, Alwin; Takabayashi, Alain; Salvatore, Giovanni Antonio; Cantarella, Giuseppe; Ortiz Perez, Alvaro; Wöllenstein, Jürgen; Palzer, Stefan; Tröster, Gerhard

    2018-01-26

    We present a gas sensitive thin-film transistor (TFT) based on an amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) semiconductor as the sensing layer, which is fabricated on a free-standing flexible polyimide foil. The photo-induced sensor response to NO₂ gas at room temperature and the cross-sensitivity to humidity are investigated. We combine the advantages of a transistor based sensor with flexible electronics technology to demonstrate the first flexible a-IGZO based gas sensitive TFT. Since flexible plastic substrates prohibit the use of high operating temperatures, the charge generation is promoted with the help of UV-light absorption, which ultimately triggers the reversible chemical reaction with the trace gas. Furthermore, the device fabrication process flow can be directly implemented in standard TFT technology, allowing for the parallel integration of the sensor and analog or logical circuits.

  9. Photo-Induced Room-Temperature Gas Sensing with a-IGZO Based Thin-Film Transistors Fabricated on Flexible Plastic Foil

    PubMed Central

    Bierer, Benedikt; Takabayashi, Alain; Ortiz Perez, Alvaro; Wöllenstein, Jürgen

    2018-01-01

    We present a gas sensitive thin-film transistor (TFT) based on an amorphous Indium–Gallium–Zinc–Oxide (a-IGZO) semiconductor as the sensing layer, which is fabricated on a free-standing flexible polyimide foil. The photo-induced sensor response to NO2 gas at room temperature and the cross-sensitivity to humidity are investigated. We combine the advantages of a transistor based sensor with flexible electronics technology to demonstrate the first flexible a-IGZO based gas sensitive TFT. Since flexible plastic substrates prohibit the use of high operating temperatures, the charge generation is promoted with the help of UV-light absorption, which ultimately triggers the reversible chemical reaction with the trace gas. Furthermore, the device fabrication process flow can be directly implemented in standard TFT technology, allowing for the parallel integration of the sensor and analog or logical circuits. PMID:29373524

  10. Enhanced electrical stability of nitrate ligand-based hexaaqua complexes solution-processed ultrathin a-IGZO transistors

    NASA Astrophysics Data System (ADS)

    Choi, C.; Baek, Y.; Lee, B. M.; Kim, K. H.; Rim, Y. S.

    2017-12-01

    We report solution-processed, amorphous indium-gallium-zinc-oxide-based (a-IGZO-based) thin-film transistors (TFTs). Our proposed solution-processed a-IGZO films, using a simple spin-coating method, were formed through nitrate ligand-based metal complexes, and they were annealed at low temperature (250 °C) to achieve high-quality oxide films and devices. We investigated solution-processed a-IGZO TFTs with various thicknesses, ranging from 4 to 16 nm. The 4 nm-thick TFT films had smooth morphology and high-density, and they exhibited excellent performance, i.e. a high saturation mobility of 7.73  ±  0.44 cm2 V-1 s-1, a sub-threshold swing of 0.27 V dec-1, an on/off ratio of ~108, and a low threshold voltage of 3.10  ±  0.30 V. However, the performance of the TFTs degraded as the film thickness was increased. We further performed positive and negative bias stress tests to examine their electrical stability, and it was noted that the operating behavior of the devices was highly stable. Despite a small number of free charges, the high performance of the ultrathin a-IGZO TFTs was attributed to the small effect of the thickness of the channel, low bulk resistance, the quality of the a-IGZO/SiO2 interface, and high film density.

  11. Bias stress instability of double-gate a-IGZO TFTs on polyimide substrate

    NASA Astrophysics Data System (ADS)

    Cho, Won-Ju; Ahn, Min-Ju

    2017-09-01

    In this study, flexible double-gate thin-film transistor (TFT)-based amorphous indium-galliumzinc- oxide (a-IGZO) was fabricated on a polyimide substrate. Double-gate operation with connected front and back gates was compared with a single-gate operation. As a result, the double-gate a- IGZO TFT exhibited enhanced electrical characteristics as well as improved long-term reliability. Under positive- and negative-bias temperature stress, the threshold voltage shift of the double-gate operation was much smaller than that of the single-gate operation.

  12. Effect of stiffness modulation on mechanical stability of stretchable a-IGZO TFTs

    NASA Astrophysics Data System (ADS)

    Park, Hyungjin; Cho, Kyoungah; Oh, Hyungon; Kim, Sangsig

    2018-05-01

    In this study, we fabricate the amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) on a stretchable substrate with a buffer stage and investigate the mechanical stability and electrical characteristics when the length of the substrate is stretched by 1.7 times. The buffer stage is responsible for the stiffness modulation of the stretchable substrate. The mobility, the threshold voltage and the on/off ratio of the stretchable a-IGZO TFT are measured to be 18.1 cm2/V·s, 1 V, and 3 × 107, respectively. Our simulation conducted by a three dimensional finite elements method reveals that the stiffness modulation reduces the stress experienced by the substrate in the stretched state by about one-tenth. In addition, the mechanical stability and electrical characteristics of the a-IGZO TFT are maintained even when the substrate is stretched by 1.7 times.

  13. Effect of Post Treatment For Cu-Cr Source/Drain Electrodes on a-IGZO TFTs.

    PubMed

    Hu, Shiben; Fang, Zhiqiang; Ning, Honglong; Tao, Ruiqiang; Liu, Xianzhe; Zeng, Yong; Yao, Rihui; Huang, Fuxiang; Li, Zhengcao; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao

    2016-07-27

    We report a high-performance amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistor (TFT) with new copper-chromium (Cu-Cr) alloy source/drain electrodes. The TFT shows a high mobility of 39.4 cm 2 ·V - 1 ·s - 1 a turn-on voltage of -0.8 V and a low subthreshold swing of 0.47 V/decade. Cu diffusion is suppressed because pre-annealing can protect a-IGZO from damage during the electrode sputtering and reduce the copper diffusion paths by making film denser. Due to the interaction of Cr with a-IGZO, the carrier concentration of a-IGZO, which is responsible for high mobility, rises.

  14. Effect of Post Treatment For Cu-Cr Source/Drain Electrodes on a-IGZO TFTs

    PubMed Central

    Hu, Shiben; Fang, Zhiqiang; Ning, Honglong; Tao, Ruiqiang; Liu, Xianzhe; Zeng, Yong; Yao, Rihui; Huang, Fuxiang; Li, Zhengcao; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao

    2016-01-01

    We report a high-performance amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistor (TFT) with new copper-chromium (Cu-Cr) alloy source/drain electrodes. The TFT shows a high mobility of 39.4 cm2·V−1·s−1 a turn-on voltage of −0.8 V and a low subthreshold swing of 0.47 V/decade. Cu diffusion is suppressed because pre-annealing can protect a-IGZO from damage during the electrode sputtering and reduce the copper diffusion paths by making film denser. Due to the interaction of Cr with a-IGZO, the carrier concentration of a-IGZO, which is responsible for high mobility, rises. PMID:28773743

  15. Structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics for a-IGZO thin-film transistors

    PubMed Central

    2013-01-01

    In this letter, we investigated the structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics on the amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) devices. Compared with the Er2O3 dielectric, the a-IGZO TFT device incorporating an Er2TiO5 gate dielectric exhibited a low threshold voltage of 0.39 V, a high field-effect mobility of 8.8 cm2/Vs, a small subthreshold swing of 143 mV/decade, and a high Ion/Ioff current ratio of 4.23 × 107, presumably because of the reduction in the oxygen vacancies and the formation of the smooth surface roughness as a result of the incorporation of Ti into the Er2TiO5 film. Furthermore, the reliability of voltage stress can be improved using an Er2TiO5 gate dielectric. PMID:23294730

  16. Structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics for a-IGZO thin-film transistors.

    PubMed

    Chen, Fa-Hsyang; Her, Jim-Long; Shao, Yu-Hsuan; Matsuda, Yasuhiro H; Pan, Tung-Ming

    2013-01-08

    In this letter, we investigated the structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics on the amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) devices. Compared with the Er2O3 dielectric, the a-IGZO TFT device incorporating an Er2TiO5 gate dielectric exhibited a low threshold voltage of 0.39 V, a high field-effect mobility of 8.8 cm2/Vs, a small subthreshold swing of 143 mV/decade, and a high Ion/Ioff current ratio of 4.23 × 107, presumably because of the reduction in the oxygen vacancies and the formation of the smooth surface roughness as a result of the incorporation of Ti into the Er2TiO5 film. Furthermore, the reliability of voltage stress can be improved using an Er2TiO5 gate dielectric.

  17. Low temperature annealed amorphous indium gallium zinc oxide (a-IGZO) as a pH sensitive layer for applications in field effect based sensors

    SciTech Connect

    Kumar, Narendra; Samtel Centre for Display Technologies, Indian Institute of Technology Kanpur, Kanpur-208016; Kumar, Jitendra

    The use of a-IGZO instead of the conventional high-k dielectrics as a pH sensitive layer could lead to the simplification of fabrication steps of field effect based devices. In this work, the pH sensitivities of a-IGZO films directly deposited over a SiO{sub 2}/Si surface were studied utilizing electrolyte-insulator-semiconductor (EIS) structures. Annealing of the films was found to affect the sensitivity of the devices and the device with the film annealed at 400 {sup o}C in N{sub 2} ambience showed the better sensitivity, which reduced with further increase in the annealing temperature to 500 {sup o}C. The increased pH sensitivity withmore » the film annealed at 400 {sup o}C in N{sub 2} gas was attributed to the enhanced lattice oxygen ions (based on the XPS data) and improved C-V characteristics, while the decrease in sensitivity at an increased annealing temperature of 500 {sup o}C was attributed to defects in the films as well as the induced traps at the IGZO/SiO{sub 2} interface based on the stretched accumulation and the peak in the inversion region of C-V curves. This study could help to develop a sensor where the material (a-IGZO here) used as the active layer in a thin film transistors (TFTs) possibly could also be used as the pH sensitive layer without affecting the TFT characteristics, and thus obviating the need of high-K dielectrics for sensitivity enhancement.« less

  18. Effect of O2 plasma treatment on density-of-states in a-IGZO thin film transistors

    NASA Astrophysics Data System (ADS)

    Ding, Xingwei; Huang, Fei; Li, Sheng; Zhang, Jianhua; Jiang, Xueyin; Zhang, Zhilin

    2017-01-01

    This work reports an efficient route for enhancing the performance of amorphous InGaZnO (a-IGZO) thin film transistors (TFT). The mobility was greatly improved by about 38% by means of O2 plasma treatment. Temperature-stress was carried out to investigate the stability and extract the parameters related to activation energy ( E a) and density-of-states (DOS). The DOS was calculated on the basis of the experimentally obtained E a, which can explain the experimental observation. A lower activation energy ( E a, 0.72 eV) and a smaller DOS were obtained in the O2 plasma treatment TFT based on the temperature-dependent transfer curves. The results showed that temperature stability and electrical properties enhancements in a-IGZO thin film transistors were attributed to the smaller DOS. [Figure not available: see fulltext.

  19. Ionic liquid versus SiO 2 gated a-IGZO thin film transistors: A direct comparison

    DOE PAGES

    Pudasaini, Pushpa Raj; Noh, Joo Hyon; Wong, Anthony T.; ...

    2015-08-12

    Here, ionic liquid gated field effect transistors have been extensively studied due to their low operation voltage, ease of processing and the realization of high electric fields at low bias voltages. Here, we report ionic liquid (IL) gated thin film transistors (TFTs) based on amorphous Indium Gallium Zinc Oxide (a-IGZO) active layers and directly compare the characteristics with a standard SiO 2 gated device. The transport measurements of the top IL gated device revealed the n-channel property of the IGZO thin film with a current ON/OFF ratio ~10 5, a promising field effect mobility of 14.20 cm 2V –1s –1,more » and a threshold voltage of 0.5 V. Comparable measurements on the bottom SiO2 gate insulator revealed a current ON/OFF ratio >108, a field effect mobility of 13.89 cm 2V –1s –1 and a threshold voltage of 2.5 V. Furthermore, temperature-dependent measurements revealed that the ionic liquid electric double layer can be “frozen-in” by cooling below the glass transition temperature with an applied electrical bias. Positive and negative freezing bias locks-in the IGZO TFT “ON” and “OFF” state, respectively, which could lead to new switching and possibly non-volatile memory applications.« less

  20. Ionic liquid versus SiO 2 gated a-IGZO thin film transistors: A direct comparison

    SciTech Connect

    Pudasaini, Pushpa Raj; Noh, Joo Hyon; Wong, Anthony T.

    Here, ionic liquid gated field effect transistors have been extensively studied due to their low operation voltage, ease of processing and the realization of high electric fields at low bias voltages. Here, we report ionic liquid (IL) gated thin film transistors (TFTs) based on amorphous Indium Gallium Zinc Oxide (a-IGZO) active layers and directly compare the characteristics with a standard SiO 2 gated device. The transport measurements of the top IL gated device revealed the n-channel property of the IGZO thin film with a current ON/OFF ratio ~10 5, a promising field effect mobility of 14.20 cm 2V –1s –1,more » and a threshold voltage of 0.5 V. Comparable measurements on the bottom SiO2 gate insulator revealed a current ON/OFF ratio >108, a field effect mobility of 13.89 cm 2V –1s –1 and a threshold voltage of 2.5 V. Furthermore, temperature-dependent measurements revealed that the ionic liquid electric double layer can be “frozen-in” by cooling below the glass transition temperature with an applied electrical bias. Positive and negative freezing bias locks-in the IGZO TFT “ON” and “OFF” state, respectively, which could lead to new switching and possibly non-volatile memory applications.« less

  1. Polyfluorene light-emitting devices and amorphous silicon:hydrogen TFT pixel circuits for active-matrix organic light-emitting displays

    NASA Astrophysics Data System (ADS)

    He, Yi

    2000-10-01

    Organic light-emitting devices (OLEDs) made of single-layer and double-layer polymer thin films have been fabricated and studied. The hole transporting (polymer A) and emissive (polymer B) polymers were poly(9,9' -dioctyl fluorene-2,7-diyl)-co-poly(diphenyl-p-tolyl-amine-4,4 '-diyl) and poly(9,9'-dioctyl fluorene-2,7-diyl)-co-poly(benzothiadiazole 2,5-diyl), respectively. The optical bandgaps of polymer A and B were 2.72 and 2.82 eV, respectively. The photoluminescence (PL) peaks for polymer A and B were 502 and 546 nm, respectively. The electroluminescence (EL) peak for polymer B was 547 nm. No EL has been observed from polymer A single layer OLEDs. To obtain the spectral distribution of the emission properties of the light-emitting devices, a new light-output measurement technique was developed. Using this technique, the spectral distribution of the luminance, radiance, photon density emission can be obtained. Moreover, the device external quantum efficiency calculated using this technique is accurate and insensitive to the light emission spectrum shape. Organic light-emitting devices have been fabricated and studied on both glass and flexible plastic substrates. The OLEDs showed a near-linear relationship between the luminance and the applied current density over four orders of magnitude. For the OLEDs fabricated on the glass substrate, luminance ˜9,300 cd/m2, emission efficiency ˜14.5 cd/A, luminescence power efficiency ˜2.26 lm/W, and external quantum efficiency ˜3.85% have been achieved. For the OLEDs fabricated on the flexible plastic substrates, both aluminum and calcium were used as cathode materials. The achieved maximum OLED luminance, emission efficiency, luminescence power efficiency, and external quantum efficiency were ˜13,000 cd/m2, ˜66.1 cd/A, ˜17.2 lm/W, and 16.7%, respectively. To make an active-matrix organic light-emitting display (AM-OLED), a two-TFT pixel electrode circuit was designed and fabricated based on amorphous silicon TFT

  2. Low-temperature fabrication of sputtered high-k HfO2 gate dielectric for flexible a-IGZO thin film transistors

    NASA Astrophysics Data System (ADS)

    Yao, Rihui; Zheng, Zeke; Xiong, Mei; Zhang, Xiaochen; Li, Xiaoqing; Ning, Honglong; Fang, Zhiqiang; Xie, Weiguang; Lu, Xubing; Peng, Junbiao

    2018-03-01

    In this work, low temperature fabrication of a sputtered high-k HfO2 gate dielectric for flexible a-IGZO thin film transistors (TFTs) on polyimide substrates was investigated. The effects of Ar-pressure during the sputtering process and then especially the post-annealing treatments at low temperature (≤200 °C) for HfO2 on reducing the density of defects in the bulk and on the surface were systematically studied. X-ray reflectivity, UV-vis and X-ray photoelectron spectroscopy, and micro-wave photoconductivity decay measurements were carried out and indicated that the high quality of optimized HfO2 film and its high dielectric properties contributed to the low concentration of structural defects and shallow localized defects such as oxygen vacancies. As a result, the well-structured HfO2 gate dielectric exhibited a high density of 9.7 g/cm3, a high dielectric constant of 28.5, a wide optical bandgap of 4.75 eV, and relatively low leakage current. The corresponding flexible a-IGZO TFT on polyimide exhibited an optimal device performance with a saturation mobility of 10.3 cm2 V-1 s-1, an Ion/Ioff ratio of 4.3 × 107, a SS value of 0.28 V dec-1, and a threshold voltage (Vth) of 1.1 V, as well as favorable stability under NBS/PBS gate bias and bending stress.

  3. Heavily doped n-type a-IGZO by F plasma treatment and its thermal stability up to 600 °C

    NASA Astrophysics Data System (ADS)

    Um, Jae Gwang; Jang, Jin

    2018-04-01

    We report the electrical properties and thermal stability of heavily doped, amorphous indium-gallium-zinc-oxide (a-IGZO) treated with fluorine (F) plasma. When the F doping concentration in a-IGZO is 17.51 × 1021/cm-3, the a-IGZO exhibits a carrier concentration of 6 × 1019 cm-3, a resistivity of 3 × 10-3 Ω cm, and a Hall mobility of 20 cm2/V s. This indicates that F is a suitable n-type dopant in a-IGZO. The similarity of the ionic radius of F to that of oxygen (O) allows substitutional doping by replacing O with F or the occupation of the oxygen vacancy (VO) site by F and consequent reduction in defect density. The semiconducting property of a-IGZO can change into metallic behavior by F doping. The defect passivation by F incorporation is confirmed by the XPS depth profile, which reveals the significant reduction in the VO concentration due to the formation of In-F bonds. The heavily doped a-IGZO exhibits thermally stable conductivity up to 600 °C annealing and thus can be widely used for the ohmic contact of a-IGZO devices.

  4. High-performance SEGISFET pH Sensor using the structure of double-gate a-IGZO TFTs with engineered gate oxides

    NASA Astrophysics Data System (ADS)

    Pyo, Ju-Young; Cho, Won-Ju

    2017-03-01

    In this paper, we propose a high-performance separative extended gate ion-sensitive field-effect transistor (SEGISFET) that consists of a tin dioxide (SnO2) SEG sensing part and a double-gate structure amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor (TFT) with tantalum pentoxide/silicon dioxide (Ta2O5/SiO2)-engineered top-gate oxide. To increase sensitivity, we maximized the capacitive coupling ratio by applying high-k dielectric at the top-gate oxide layer. As an engineered top-gate oxide, a stack of 25 nm-thick Ta2O5 and 10 nm-thick SiO2 layers was found to simultaneously satisfy a small equivalent oxide thickness (˜17.14 nm), a low leakage current, and a stable interfacial property. The threshold-voltage instability, which is a fundamental issue in a-IGZO TFTs, was improved by low-temperature post-deposition annealing (˜87 °C) using microwave irradiation. The double-gate structure a-IGZO TFTs with engineered top-gate oxide exhibited high mobility, small subthreshold swing, high drive current, and larger on/off current ratio. The a-IGZO SEGISFETs with a dual-gate sensing mode showed a pH sensitivity of 649.04 mV pH-1, which is far beyond the Nernst limit. The non-ideal behavior of ISFETs, hysteresis, and drift effect also improved. These results show that the double-gate structure a-IGZO TFTs with engineered top-gate oxide can be a good candidate for cheap and disposable SEGISFET sensors.

  5. Scaling behavior of fully spin-coated TFT

    NASA Astrophysics Data System (ADS)

    Mondal, Sandip; Kumar, Arvind; Rao, K. S. R. Koteswara; Venkataraman, V.

    2017-05-01

    We studied channel scaling behavior of fully spin coated, low temperature solution processed thin film transistor (TFT) fabricated on p++ - Si (˜1021 cm-3) as bottom gate. The solution processed, spin coated 40 nm thick amorphous Indium Gallium Zinc Oxide (a-IGZO) and 50 nm thick amorphous zirconium di-oxide (a-ZrO2) has been used as channel and low leakage dielectric at 350°C respectively. The channel scaling effect of the TFT with different width/length ratio (W/L= 2.5, 5 and 15) for same channel length (L = 10 μm) has been demonstrated. The lowest threshold voltage (Vth) is 6.25 V for the W/L=50/10. The maximum field effect mobility (μFE) has been found to be 0.123 cm2/Vs from W/L of 50/10 with the drain to source voltage (VD) of 10V and 20V gate to source voltage (VG). We also demonstrated that there is no contact resistance effect on the mobility of the fully sol-gel spin coated TFT.

  6. Improvement of the positive bias stability of a-IGZO TFTs by the HCN treatment

    NASA Astrophysics Data System (ADS)

    Kim, Myeong-Ho; Choi, Myung-Jea; Kimura, Katsuya; Kobayashi, Hikaru; Choi, Duck-Kyun

    2016-12-01

    In recent years, many researchers have attempted to improve the bias stability of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs). In this study, the hydrogen cyanide (HCN) treatment was carried out to improve the positive bias stability of bottom-gate a-IGZO TFTs. The HCN treatment was performed using a 0.1 M HCN solution with a pH of 10 at room temperature. Before applying the positive bias stress, there were no differences in the major electrical properties, including the saturation mobility (μsat), threshold voltage (Vth), and subthreshold swing (S/S), between HCN-treated and non-HCN-treated devices. However, after applying the positive bias stress, the HCN-treated device showed superior bias stability compared to the non-HCN-treated device. This difference is associated with the passivation of the defect states and the surface of the back-channel layer of the HCN-treated device by cyanide ions.

  7. Fabrication of an a-IGZO thin film transistor using selective deposition of cobalt by the self-assembly monolayer (SAM) process.

    PubMed

    Cho, Young-Je; Kim, HyunHo; Park, Kyoung-Yun; Lee, Jaegab; Bobade, Santosh M; Wu, Fu-Chung; Choi, Duck-Kyun

    2011-01-01

    Interest in transparent oxide thin film transistors utilizing ZnO material has been on the rise for many years. Recently, however, IGZO has begun to draw more attention due to its higher stability and superior electric field mobility when compared to ZnO. In this work, we address an improved method for patterning an a-IGZO film using the SAM process, which employs a cost-efficient micro-contact printing method instead of the conventional lithography process. After a-IGZO film deposition on the surface of a SiO2-layered Si wafer, the wafer was illuminated with UV light; sources and drains were then patterned using n-octadecyltrichlorosilane (OTS) molecules by a printing method. Due to the low surface energy of OTS, cobalt was selectively deposited on the OTS-free a-IGZO surface. The selective deposition of cobalt electrodes was successful, as confirmed by an optical microscope. The a-IZGO TFT fabricated using the SAM process exhibited good transistor performance: electric field mobility (micro(FE)), threshold voltage (V(th)), subthreshold slope (SS) and on/off ratio were 2.1 cm2/Vs, 2.4 V, 0.35 V/dec and 2.9 x 10(6), respectively.

  8. Oligonucleotide-arrayed TFT photosensor applicable for DNA chip technology.

    PubMed

    Tanaka, Tsuyoshi; Hatakeyama, Keiichi; Sawaguchi, Masahiro; Iwadate, Akihito; Mizutani, Yasushi; Sasaki, Kazuhiro; Tateishi, Naofumi; Takeyama, Haruko; Matsunaga, Tadashi

    2006-09-05

    A thin film transistor (TFT) photosensor fabricated by semiconductor integrated circuit (IC) technology was applied to DNA chip technology. The surface of the TFT photosensor was coated with TiO2 using a vapor deposition technique for the fabrication of optical filters. The immobilization of thiolated oligonucleotide probes onto a TiO2-coated TFT photosensor using gamma-aminopropyltriethoxysilane (APTES) and N-(gamma-maleimidobutyloxy) sulfosuccinimide ester (GMBS) was optimized. The coverage value of immobilized oligonucleotides reached a plateau at 33.7 pmol/cm2, which was similar to a previous analysis using radioisotope-labeled oligonucleotides. The lowest detection limits were 0.05 pmol/cm2 for quantum dot and 2.1 pmol/cm2 for Alexa Fluor 350. Furthermore, single nucleotide polymorphism (SNP) detection was examined using the oligonucleotide-arrayed TFT photosensor. A SNP present in the aldehyde dehydrogenase 2 (ALDH2) gene was used as a target. The SNPs in ALDH2*1 and ALDH2*2 target DNA were detected successfully using the TFT photosensor. DNA hybridization in the presence of both ALDH2*1 and ALDH2*2 target DNA was observed using both ALDH2*1 and ALDH2*2 detection oligonucleotides-arrayed TFT photosensor. Use of the TFT photosensor will allow the development of a disposable photodetecting device for DNA chip systems. (c) 2006 Wiley Periodicals, Inc.

  9. Reduced contact resistance of a-IGZO thin film transistors with inkjet-printed silver electrodes

    NASA Astrophysics Data System (ADS)

    Chen, Jianqiu; Ning, Honglong; Fang, Zhiqiang; Tao, Ruiqiang; Yang, Caigui; Zhou, Yicong; Yao, Rihui; Xu, Miao; Wang, Lei; Peng, Junbiao

    2018-04-01

    In this study, high performance amorphous In–Ga–Zn–O (a-IGZO) TFTs were successfully fabricated with inkjet-printed silver source-drain electrodes. The results showed that increased channel thickness has an improving trend in the properties of TFTs due to the decreased contact resistance. Compared with sputtered silver TFTs, devices with printed silver electrodes were more sensitive to the thickness of active layer. Furthermore, the devices with optimized active layer showed high performances with a maximum saturation mobility of 8.73 cm2 · V‑1 · S‑1 and an average saturation mobility of 6.97 cm2 · V‑1 · S‑1, I on/I off ratio more than 107 and subthreshold swing of 0.28 V/decade, which were comparable with the analogous devices with sputtered electrodes.

  10. Hydrogen anion and subgap states in amorphous In-Ga-Zn-O thin films for TFT applications

    NASA Astrophysics Data System (ADS)

    Bang, Joonho; Matsuishi, Satoru; Hosono, Hideo

    2017-06-01

    Hydrogen is an impurity species having an important role in the physical properties of semiconductors. Despite numerous studies, the role of hydrogen in oxide semiconductors remains an unsolved puzzle. This situation arises from insufficient information about the chemical state of the impurity hydrogen. Here, we report direct evidence for anionic hydrogens bonding to metal cations in amorphous In-Ga-Zn-O (a-IGZO) thin films for thin-film transistors (TFT) applications and discuss how the hydrogen impurities affect the electronic structure of a-IGZO. Infrared absorption spectra of self-standing a-IGZO thin films prepared by sputtering reveal the presence of hydrogen anions as a main hydrogen species (concentration is ˜1020 cm-3) along with the hydrogens in the form of the hydroxyl groups (˜1020 cm-3). Density functional theory calculations show that bonds between these hydride ions with metal centers give rise to subgap states above the top of the valence band, implying a crucial role of anionic hydrogen in the negative bias illumination stress instability commonly observed in a-IGZO TFTs.

  11. Characteristics of a-IGZO/ITO hybrid layer deposited by magnetron sputtering.

    PubMed

    Bang, Joon-Ho; Park, Hee-Woo; Cho, Sang-Hyun; Song, Pung-Keun

    2012-04-01

    Transparent a-IGZO (In-Ga-Zn-O) films have been actively studied for use in the fabrication of high-quality TFTs. In this study, a-IGZO films and a-IGZO/ITO double layers were deposited by DC magnetron sputtering under various oxygen flow rates. The a-IGZO films showed an amorphous structure up to 500 degrees C. The deposition rate of these films decreased with an increase in the amount of oxygen gas. The amount of indium atoms in the film was confirmed to be 11.4% higher than the target. The resistivity of double layer follows the rules for parallel DC circuits The maximum Hall mobility of the a-IGZO/ITO double layers was found to be 37.42 cm2/V x N s. The electrical properties of the double layers were strongly dependent on their thickness ratio. The IGZO/ITO double layer was subjected to compressive stress, while the ITO/IGZO double layer was subjected to tensile stress. The bending tolerance was found to depend on the a-IGZO thickness.

  12. The effect of a source-contacted light shield on the electrical characteristics of an LTPS TFT

    NASA Astrophysics Data System (ADS)

    Kim, Miryeon; Sun, Wookyung; Kang, Jongseuk; Shin, Hyungsoon

    2017-08-01

    The electrical characteristics of a low-temperature polycrystalline silicon thin-film transistor (TFT) with a source-contacted light shield (SCLS) are observed and analyzed. Compared with that of a conventional TFT without a light shield (LS), the on-current of the TFT with an SCLS is lower because the SCLS blocks the fringing electric field from the drain to the active layer. Furthermore, the gate-to-source capacitance (C gs) of the TFT with an SCLS in the off and saturation regions is higher than that of a conventional TFT, which is due to the gate-to-LS capacitance (C g-LS). The electrical characteristics of the TFT with an SCLS are thoroughly investigated by two-dimensional device simulations, and a semi-empirical C g-LS model for SPICE simulation is proposed and verified.

  13. Effects of structure and oxygen flow rate on the photo-response of amorphous IGZO-based photodetector devices

    NASA Astrophysics Data System (ADS)

    Jang, Jun Tae; Ko, Daehyun; Choi, Sungju; Kang, Hara; Kim, Jae-Young; Yu, Hye Ri; Ahn, Geumho; Jung, Haesun; Rhee, Jihyun; Lee, Heesung; Choi, Sung-Jin; Kim, Dong Myong; Kim, Dae Hwan

    2018-02-01

    In this study, we investigated how the structure and oxygen flow rate (OFR) during the sputter-deposition affects the photo-responses of amorphous indium-gallium-zinc-oxide (a-IGZO)-based photodetector devices. As the result of comparing three types of device structures with one another, which are a global Schottky diode, local Schottky diode, and thin-film transistor (TFT), the IGZO TFT with the gate pulse technique suppressing the persistent photoconductivity (PPC) is the most promising photodetector in terms of a high photo-sensitivity and uniform sensing characteristic. In order to analyze the IGZO TFT-based photodetectors more quantitatively, the time-evolution of sub-gap density-of-states (DOS) was directly observed under photo-illumination and consecutively during the PPC-compensating period with applying the gate pulse. It shows that the increased ionized oxygen vacancy (VO2+) defects under photo-illumination was fully recovered by the positive gate pulse and even overcompensated by additional electron trapping. Based on experimentally extracted sub-gap DOS, the origin on PPC was successfully decomposed into the hole trapping and the VO ionization. Although the VO ionization is enhanced in lower OFR (O-poor) device, the PPC becomes more severe in high OFR (O-rich) device because the hole trapping dominates the PPC in IGZO TFT under photo-illumination rather than the VO ionization and more abundant holes are trapped into gate insulator and/or interface in O-rich TFTs. Similarly, the electron trapping during the PPC-compensating period with applying the positive gate pulse becomes more prominent in O-rich TFTs. It is attributed to more hole/electron traps in the gate insulator and/or interface, which is associated with oxygen interstitials, or originates from the ion bombardment-related lower quality gate oxide in O-rich devices.

  14. Densification of a-IGZO with low-temperature annealing for flexible electronics applications

    NASA Astrophysics Data System (ADS)

    Troughton, J. G.; Downs, P.; Price, R.; Atkinson, D.

    2017-01-01

    Amorphous InGaZnO (a-IGZO) thin-film transistors are a leading contender for active channel materials in next generation flat panel displays and flexible electronics. Improved electronic functionality has been linked to the increased density of a-IGZO, and while much work has looked at high-temperature processes, studies at temperatures compatible with flexible substrates are needed. Here, compositional and structural analyses show that short term, low-temperature annealing (<6 h) can increase the density of sputtered a-IGZO by up to 5.6% for temperatures below 300 °C, which is expected to improve the transistor performance, while annealing for longer times leads to a subsequent decrease in density due to oxygen absorption.

  15. Semi-transparent a-IGZO thin-film transistors with polymeric gate dielectric.

    PubMed

    Hyung, Gun Woo; Wang, Jian-Xun; Li, Zhao-Hui; Koo, Ja-Ryong; Kwon, Sang Jik; Cho, Eou-Sik; Kim, Young Kwan

    2013-06-01

    We report the fabrication of semi-transparent a-IGZO-based thin-film transistors (TFTs) with crosslinked poly-4-vinylphenol (PVP) gate dielectric layers on PET substrate and thermally-evaporated Al/Ag/Al source and drain (S&D) electrodes, which showed a transmittance of 64% at a 500-nm wavelength and sheet resistance of 16.8 omega/square. The semi-transparent a-IGZO TFTs with a PVP layer exhibited decent saturation mobilities (maximum approximately 5.8 cm2Ns) and on/off current ratios of approximately 10(6).

  16. IGZO TFT-based circuit with tunable threshold voltage by laser annealing

    NASA Astrophysics Data System (ADS)

    Huang, Xiaoming; Yu, Guang; Wu, Chenfei

    2017-11-01

    In this work, a high-performance inverter based on amorphous indium-gallium-zinc oxide thin-film transistors (TFTs) has been fabricated, which consists of a driver TFT and a load TFT. The threshold voltage (Vth) of the load TFT can be tuned by applying an area-selective laser annealing. The transfer curve of the load TFT shows a parallel shift into the negative bias direction upon laser annealing. Based on x-ray photoelectron spectroscopy analyses, the negative Vth shift can be attributed to the increase of oxygen vacancy concentration within the device channel upon laser irradiation. Compared to the untreated inverter, the laser annealed inverter shows much improved switching characteristics, including a large output swing range which is close to full swing, as well as an enhanced output voltage gain. Furthermore, the dynamic performance of ring oscillator based on the laser-annealed inverter is improved.

  17. State of the art of fine patterned Si TFT

    NASA Astrophysics Data System (ADS)

    Noguchi, Takashi

    2003-05-01

    Performance and relating subject for fine patterned Si TFT (Thin Film Transistor) are reviewed and discussed from a viewpoint of device and/or fabrication process based on reported results. Poly-Si TFTs fabricated on glass using low-temperature process are studied extensively for the application to LCD (Liquid Crystal Display) or OLED (Organic Light Emitting Diode) Display. Currently, the research target for the TFT application is emphasized on the highly functional system on glass or the display on flexible substrate by adopting an effective crystallizing technique of SPC (Solid Phase Crystallization) or ELC (Excimer Laser Crystallization). Improvement of device characteristics such as an enhancement of carrier mobility has been studied intensively by enlarging the grain size. Reduction of the voltage and shrinkage of the device size are the trend of Si LSI, which arise a peculiar issue of uniformity or an anisotropy problem for the device characteristics in the large grained poly-Si film. Some trial approaches for solving the issues such as nucleation control for the grain growth or lateral grain growth are proposed, so far. By overcoming the issues, coming SOP (System on Panel) era using the Si TFTs is expected.

  18. In2Ga2ZnO7 oxide semiconductor based charge trap device for NAND flash memory.

    PubMed

    Hwang, Eun Suk; Kim, Jun Shik; Jeon, Seok Min; Lee, Seung Jun; Jang, Younjin; Cho, Deok-Yong; Hwang, Cheol Seong

    2018-04-01

    The programming characteristics of charge trap flash memory device adopting amorphous In 2 Ga 2 ZnO 7 (a-IGZO) oxide semiconductors as channel layer were evaluated. Metal-organic chemical vapor deposition (MOCVD) and RF-sputtering processes were used to grow a 45 nm thick a-IGZO layer on a 20 nm thick SiO 2 (blocking oxide)/p ++ -Si (control gate) substrate, where 3 nm thick atomic layer deposited Al 2 O 3 (tunneling oxide) and 5 nm thick low-pressure CVD Si 3 N 4 (charge trap) layers were intervened between the a-IGZO and substrate. Despite the identical stoichiometry and other physicochemical properties of the MOCVD and sputtered a-IGZO, a much faster programming speed of MOCVD a-IGZO was observed. A comparable amount of oxygen vacancies was found in both MOCVD and sputtered a-IGZO, confirmed by x-ray photoelectron spectroscopy and bias-illumination-instability test measurements. Ultraviolet photoelectron spectroscopy analysis revealed a higher Fermi level (E F ) of the MOCVD a-IGZO (∼0.3 eV) film than that of the sputtered a-IGZO, which could be ascribed to the higher hydrogen concentration in the MOCVD a-IGZO film. Since the programming in a flash memory device is governed by the tunneling of electrons from the channel to charge trapping layer, the faster programming performance could be the result of a higher E F of MOCVD a-IGZO.

  19. In2Ga2ZnO7 oxide semiconductor based charge trap device for NAND flash memory

    NASA Astrophysics Data System (ADS)

    Hwang, Eun Suk; Kim, Jun Shik; Jeon, Seok Min; Lee, Seung Jun; Jang, Younjin; Cho, Deok-Yong; Hwang, Cheol Seong

    2018-04-01

    The programming characteristics of charge trap flash memory device adopting amorphous In2Ga2ZnO7 (a-IGZO) oxide semiconductors as channel layer were evaluated. Metal-organic chemical vapor deposition (MOCVD) and RF-sputtering processes were used to grow a 45 nm thick a-IGZO layer on a 20 nm thick SiO2 (blocking oxide)/p++-Si (control gate) substrate, where 3 nm thick atomic layer deposited Al2O3 (tunneling oxide) and 5 nm thick low-pressure CVD Si3N4 (charge trap) layers were intervened between the a-IGZO and substrate. Despite the identical stoichiometry and other physicochemical properties of the MOCVD and sputtered a-IGZO, a much faster programming speed of MOCVD a-IGZO was observed. A comparable amount of oxygen vacancies was found in both MOCVD and sputtered a-IGZO, confirmed by x-ray photoelectron spectroscopy and bias-illumination-instability test measurements. Ultraviolet photoelectron spectroscopy analysis revealed a higher Fermi level (E F) of the MOCVD a-IGZO (∼0.3 eV) film than that of the sputtered a-IGZO, which could be ascribed to the higher hydrogen concentration in the MOCVD a-IGZO film. Since the programming in a flash memory device is governed by the tunneling of electrons from the channel to charge trapping layer, the faster programming performance could be the result of a higher E F of MOCVD a-IGZO.

  20. Correlation between Ti source/drain contact and performance of InGaZnO-based thin film transistors

    NASA Astrophysics Data System (ADS)

    Choi, Kwang-Hyuk; Kim, Han-Ki

    2013-02-01

    Ti contact properties and their electrical contribution to an amorphous InGaZnO (a-IGZO) semiconductor-based thin film transistor (TFT) were investigated in terms of chemical, structural, and electrical considerations. TFT device parameters were quantitatively studied by a transmission line method. By comparing various a-IGZO TFT parameters with those of different Ag and Ti source/drain electrodes, Ti S/D contact with an a-IGZO channel was found to lead to a negative shift in VT (-Δ 0.52 V). This resulted in higher saturation mobility (8.48 cm2/Vs) of a-IGZO TFTs due to effective interfacial reaction between Ti and an a-IGZO semiconducting layer. Based on transmission electron microcopy, x-ray photoelectron depth profile analyses, and numerical calculation of TFT parameters, we suggest a possible Ti contact mechanism on semiconducting a-IGZO channel layers for TFTs.

  1. Comparison of pattern VEP results acquired using CRT and TFT stimulators in the clinical practice.

    PubMed

    Nagy, Balázs Vince; Gémesi, Szabolcs; Heller, Dávid; Magyar, András; Farkas, Agnes; Abrahám, György; Varsányi, Balázs

    2011-06-01

    There are several electrophysiological systems available commercially. Usually, control groups are required to compare their results, due to the differences between display types. Our aim was to examine the differences between CRT and LCD/TFT stimulators used in pattern VEP responses performed according to the ISCEV standards. We also aimed to check different contrast values toward thresholds. In order to obtain more precise results, we intended to measure the intensity and temporal response characteristics of the monitors with photometric methods. To record VEP signals, a Roland RetiPort electrophysiological system was used. The pattern VEP tests were carried out according to ISCEV protocols on a CRT and a TFT monitor consecutively. Achromatic checkerboard pattern was used at three different contrast levels (maximal, 75, 25%) using 1° and 15' check sizes. Both CRT and TFT displays were luminance and contrast matched, according to the gamma functions based on measurements at several DAC values. Monitor-specific luminance parameters were measured by means of spectroradiometric instruments. Temporal differences between the displays' electronic and radiometric signals were measured with a device specifically built for the purpose. We tested six healthy control subjects with visual acuity of at least 20/20. The tests were performed on each subject three times on different days. We found significant temporal differences between the CRT and the LCD monitors at all contrast levels and spatial frequencies. In average, the latency times were 9.0 ms (±3.3 ms) longer with the TFT stimulator. This value is in accordance with the average of the measured TFT input-output temporal difference values (10.1 ± 2.2 ms). According to our findings, measuring the temporal parameters of the TFT monitor with an adequately calibrated measurement setup and correcting the VEP data with the resulting values, the VEP signals obtained with different display types can be transformed to be

  2. CdSe TFT AMLCDE manufacturing process

    NASA Astrophysics Data System (ADS)

    Pritchard, Annette M.

    1995-06-01

    Active Matrix Liquid Crystal Displays, AMLCDs, based on Cadmium Selenide Thin Film Transistors, have been developed by Litton for a number of defence/avionics applications. Fabrication processed for the thin film transistor (TFT) arrays, color filters and liquid crystal cell assembly have been developed which enable the end product to meet the difficult environmental and performance specifications of military applications, while maintaining focus on cost and yield issues. The fabrication of the AMLCD products is now transitioning into a new production facility which has been designed specifically to meet the requirements of the defence/avionics marketplace.

  3. High-performance a-IGZO thin-film transistor with conductive indium-tin-oxide buried layer

    NASA Astrophysics Data System (ADS)

    Ahn, Min-Ju; Cho, Won-Ju

    2017-10-01

    In this study, we fabricated top-contact top-gate (TCTG) structure of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) with a thin buried conductive indium-tin oxide (ITO) layer. The electrical performance of a-IGZO TFTs was improved by inserting an ITO buried layer under the IGZO channel. Also, the effect of the buried layer's length on the electrical characteristics of a-IGZO TFTs was investigated. The electrical performance of the transistors improved with increasing the buried layer's length: a large on/off current ratio of 1.1×107, a high field-effect mobility of 35.6 cm2/Vs, a small subthreshold slope of 116.1 mV/dec, and a low interface trap density of 4.2×1011 cm-2eV-1 were obtained. The buried layer a-IGZO TFTs exhibited enhanced transistor performance and excellent stability against the gate bias stress.

  4. Flexible AMOLED backplane using pentacene TFT

    NASA Astrophysics Data System (ADS)

    Song, Chung Kun; Ryu, Gi Seong

    2005-01-01

    In this paper we fabricated a panel consisting of an array of organic TFTs (OTFT) and organic LEDs (OLED) in order to demonstrate the possible application of OTFTs to flexible active matrix OLED (AMOLED). The panel was composed of 64×64 pixels on 4 inch size PET substrate in which each pixel had one OTFT integrated with one green OLED. The panel successfully demonstrated to display some letters and pictures by emitting green light with luminance of 20 cd/m2 at 6 V, which was controlled by the gate voltage of OTFT. In addition we also developed fabrication processes for pentacene TFT with PVP gate on PET substrate. The OTFTs produced the maximum mobility of 1.2 cm2/V"sec and on/off current ratio of 2×106.

  5. Influence of white light illumination on the performance of a-IGZO thin film transistor under positive gate-bias stress

    NASA Astrophysics Data System (ADS)

    Tang, Lan-Feng; Yu, Guang; Lu, Hai; Wu, Chen-Fei; Qian, Hui-Min; Zhou, Dong; Zhang, Rong; Zheng, You-Dou; Huang, Xiao-Ming

    2015-08-01

    The influence of white light illumination on the stability of an amorphous InGaZnO thin film transistor is investigated in this work. Under prolonged positive gate bias stress, the device illuminated by white light exhibits smaller positive threshold voltage shift than the device stressed under dark. There are simultaneous degradations of field-effect mobility for both stressed devices, which follows a similar trend to that of the threshold voltage shift. The reduced threshold voltage shift under illumination is explained by a competition between bias-induced interface carrier trapping effect and photon-induced carrier detrapping effect. It is further found that white light illumination could even excite and release trapped carriers originally exiting at the device interface before positive gate bias stress, so that the threshold voltage could recover to an even lower value than that in an equilibrium state. The effect of photo-excitation of oxygen vacancies within the a-IGZO film is also discussed. Project supported by the State Key Program for Basic Research of China (Grant Nos. 2011CB301900 and 2011CB922100) and the Priority Academic Program Development of Jiangsu Higher Education Institutions, China.

  6. High-performance hybrid complementary logic inverter through monolithic integration of a MEMS switch and an oxide TFT.

    PubMed

    Song, Yong-Ha; Ahn, Sang-Joon Kenny; Kim, Min-Wu; Lee, Jeong-Oen; Hwang, Chi-Sun; Pi, Jae-Eun; Ko, Seung-Deok; Choi, Kwang-Wook; Park, Sang-Hee Ko; Yoon, Jun-Bo

    2015-03-25

    A hybrid complementary logic inverter consisting of a microelectromechanical system switch as a promising alternative for the p-type oxide thin film transistor (TFT) and an n-type oxide TFT is presented for ultralow power integrated circuits. These heterogeneous microdevices are monolithically integrated. The resulting logic device shows a distinctive voltage transfer characteristic curve, very low static leakage, zero-short circuit current, and exceedingly high voltage gain. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Electrical properties of solution processed highly transparent ZnO TFT with organic gate dielectric

    NASA Astrophysics Data System (ADS)

    Pandya, Nirav C.; Joshi, Nikhil G.; Trivedi, U. N.; Joshi, U. S.

    2013-02-01

    All oxide thin film transistors (TFT) with zinc oxide active layer were fabricated by chemical solution deposition (CSD) using aqueous solutions on glass substrate. Thin film transistors (TFTs) with amorphous zinc oxide as channel layers and poly-vinyl alcohol as dielectric layers were fabricated at low temperatures by chemical solution deposition (CSD). Atomic force microscopy (AFM) confirmed nano grain size with fairly smooth surface topography. Very small leakage currents were achieved in the transfer curves, while soft saturation was observed in the output current voltage (I-V) characteristics of the device. Optical transmission of better than 87% in the visible region was estimated, which is better than the organic gate insulator based ZnO TFTs reported so far. Our results offer lot of promise to TFT based display and optoelectronics.

  8. Fabrication of one-transistor-capacitor structure of nonvolatile TFT ferroelectric RAM devices using Ba(Zr0.1Ti0.9)O3 gated oxide film.

    PubMed

    Yang, Cheng-Fu; Chen, Kai-Huang; Chen, Ying-Chung; Chang, Ting-Chang

    2007-09-01

    In this study, the Ba(Zr0.1Ti0.9)O3 (BZ1T9) thin films have been well deposited on the Pt/Ti/SiO2/Si substrate. The optimum radio frequency (RF) deposition parameters are developed, and the BZ1T9 thin films deposition at the optimum parameters have the maximum capacitance and dielectric constant of 4.4 nF and 190. As the applied voltage is increased to 8 V, the remnant polarization and coercive field of BZ1T9 thin films are about 4.5 microC/cm2 and 80 kV/cm. The counterclockwise current hysteresis and memory window of n-channel thin-film transistor property are observed, and that can be used to indicate the switching of ferroelectric polarization of BZ1T9 thin films. One-transistor-capacitor (1TC) structure of BZ1T9 ferroelectric random access memory device using bottom-gate amorphous silicon thin-film transistor was desirable because of the smaller size and better sensitivity. The BZ1T9 ferroelectric RAM devices with channel width = 40 microm and channel length = 8 microm has been successfully fabricated and the ID-VG transfer characteristics also are investigated in this study.

  9. Effects of various gate materials on electrical degradation of a-Si:H TFT in industrial display application

    NASA Astrophysics Data System (ADS)

    Ho, Ching-Yuan; Chang, Yaw-Jen

    2016-02-01

    Both aluminum (Al) and copper (Cu), acting as transmission lines in the hydrogenated amorphous silicon of a thin film transistor (a-Si:H TFT), were studied to investigate electrical degradation including electron-migration (EM) and threshold voltage (Vt) stability and recovery performance. Under long-term current stress, the Cu material exhibited excellent resistance to EM properties, but a passivated SiNx crack was observed due to fast heat conductivity. By applying electrical stress on the gate and drain for 5 × 104 s, the power-law time dependency of the threshold voltage shift (ΔVt) indicated that the defective state creation dominated the TFT device's instability. The presence of drain stress increased the overall ΔVt because the high longitudinal field induced impact ionization and then, enhanced hot-carrier-induced electron trapping within the gate SiNx dielectric. An annealing effect prompted a stressed a-Si:H TFT back to virgin status. This study proposes better ΔVt stability and excellent resistance against electron-migration in a Cu gate device which can be considered as a candidate for a transmission line on prolonged TFT applications.

  10. Genes for 2,4,5-Trichlorophenoxyacetic Acid Metabolism in Burkholderia cepacia AC1100: Characterization of the tftC and tftD Genes and Locations of the tft Operons on Multiple Replicons

    PubMed Central

    Hübner, Anette; Danganan, Clyde E.; Xun, Luying; Chakrabarty, A. M.; Hendrickson, William

    1998-01-01

    Burkholderia cepacia AC1100 uses the chlorinated aromatic compound 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) as a sole source of carbon and energy. The enzyme which converts the first intermediate in the pathway, 2,4,5-trichlorophenol, to 5-chlorohydroquinone has been purified and consists of two subunits of 58 and 22 kDa, encoded by the tftC and tftD genes (48). A degenerate primer was designed from the N terminus of the 58-kDa polypeptide and used to isolate a clone containing the tftC and tftD genes from a genomic library of AC1100. The derived amino acid sequences of tftC and tftD show significant homology to the two-component monooxygenases HadA of Burkholderia pickettii, HpaBC of Escherichia coli, and HpaAH of Klebsiella pneumonia. Expression of the tftC and tftD genes appeared to be induced when they were grown in the presence of 2,4,5-T, as shown by RNA slot blot and primer extension analyses. Three sets of cloned tft genes were used as probes to explore the genomic organization of the pathway. Pulsed-field gel electrophoresis analyses of whole chromosomes of B. cepacia AC1100 demonstrated that the genome is comprised of five replicons of 4.0, 2.7, 0.53, 0.34, and 0.15 Mbp, designated I to V, respectively. The tft genes are located on the smaller replicons: the tftAB cluster is on replicon IV, tftEFGH is on replicon III, and copies of the tftC and the tftCD operons are found on both replicons III and IV. When cells were grown in the absence of 2,4,5-T, the genes were lost at high frequency by chromosomal deletions and rearrangements to produce 2,4,5-T-negative mutants. In one mutant, the tftA and tftB genes translocated from one replicon to another, with the concomitant loss of tftEFGH and one copy of tftCD. PMID:9603818

  11. Highly effective field-effect mobility amorphous InGaZnO TFT mediated by directional silver nanowire arrays.

    PubMed

    Liu, Hung-Chuan; Lai, Yi-Chun; Lai, Chih-Chung; Wu, Bing-Shu; Zan, Hsiao-Wen; Yu, Peichen; Chueh, Yu-Lun; Tsai, Chuang-Chuang

    2015-01-14

    In this work, we demonstrate sputtered amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) with a record high effective field-effect mobility of 174 cm(2)/V s by incorporating silver nanowire (AgNW) arrays to channel electron transport. Compared to the reference counterpart without nanowires, the over 5-fold enhancement in the effective field-effect mobility exhibits clear dependence on the orientation as well as the surface coverage ratio of silver nanowires. Detailed material and device analyses reveal that during the room-temperature IGZO sputtering indium and oxygen diffuse into the nanowire matrix while the nanowire morphology and good contact between IGZO and nanowires are maintained. The unchanged morphology and good interfacial contact lead to high mobility and air-ambient-stable characteristics up to 3 months. Neither hysteresis nor degraded bias stress reliability is observed. The proposed AgNW-mediated a-IGZO TFTs are promising for development of large-scale, flexible, transparent electronics.

  12. Quantitative SIMS depth profiling of diffusion barrier gate-oxynitride structures in TFT-LCDs.

    PubMed

    Dreer, Sabine; Wilhartitz, Peter; Piplits, Kurt; Mayerhofer, Karl; Foisner, Johann; Hutter, Herbert

    2004-06-01

    Gate oxynitride structures of TFT-LCDs were investigated by SIMS, and successful solutions are demonstrated to overcome difficulties arising due to the charging effects of the multilayer systems, the matrix effect of the method, and the small pattern sizes of the samples. Because of the excellent reproducibility achieved by applying exponential relative sensitivity functions for quantitative analysis, minor differences in the barrier gate-oxynitride composition deposited on molybdenum capped aluminium-neodymium metallisation electrodes were determined between the centre and the edge of the TFT-LCD substrates. No differences were found for molybdenum-tungsten metallisations. Furthermore, at the edge of the glass substrates, aluminium, neodymium, and molybdenum SIMS depth profiles show an exponential trend. With TEM micrographs an inhomogeneous thickness of the molybdenum capping is revealed as the source of this effect, which influences the electrical behaviour of the device. The production process was improved after these results and the aging behaviour of TFT-LCDs was investigated in order to explain the change in control voltage occurring during the lifetime of the displays. SIMS and TEM show an enrichment of neodymium at the interface to the molybdenum layer, confirming good diffusion protection of the molybdenum barrier during accelerated aging. The reason for the shift of the control voltage was finally located by semi-quantitative depth profiling of the sodium diffusion originating from the glass substrate. Molybdenum-tungsten was a much better buffer for the highly-mobile charge carriers than aluminium-neodymium. Best results were achieved with PVD silicon oxynitride as diffusion barrier and gate insulator deposited on aluminium-neodymium metallisation layers.

  13. MBR/RO/ozone processes for TFT-LCD industrial wastewater treatment and recycling.

    PubMed

    Chen, T K; Ni, C H; Chan, Y C; Lu, M C

    2005-01-01

    This research is mainly to explore the treatment capacity for TFT-LCD industrial wastewater recycling by the processes combined with membrane bioreactor (MBR), reverse osmosis (RO) and ozone(O3). The organic wastewater from the TFT-LCD industry was selected as the target. MBR, RO and ozone plants were established for evaluation. An MBR plant consisted of a 2-stage anoxic/aerobic bioreactor and an immersed UF membrane unit was employed. The effluent of MBR was conducted into the RO system then into the ozone system. The RO system consisted of a spiral membrane in the vessel. One bubble column, 75 cm high and diameter 5 cm, were used as the ozonation reactor. On the bottom of ozonation reactor is a porous diffuser for releasing gas, with an aperture of 100 microm (0.1 cm). Over the whole experimental period, the MBR process achieved a satisfactory organic removal. The COD could be removed with an average of over 98.5%. For the TOC item, the average removal efficiency was 97.4%. The stable effluent quality and satisfactory removal performance were ensured by the efficient interception performance of an immersed UF membrane device incorporated with the biological reactor. Moreover, the MBR effluent did not contain any suspended solids and the SDI value was under 3. After the treatment of RO, excellent water quality was found. The water quality of permeate was under 5 mg/I, 2 mg/l and 50 micros/cm for COD, TOC and conductivity respectively. The treated water can be recycled and reused for the cooling tower make-up water or other purposes. After the treatment of ozone, the treated water quality was under 5 mg/l and 0.852 mg/l for COD and TOC respectively. The test results of MBR, MBR/RO and MBR/RO/ozone processes were compared as possible appropriate treatment technologies applied in TFT-LCD industrial wastewater reuse and recycling.

  14. Capacitorless 1T-DRAM on crystallized poly-Si TFT.

    PubMed

    Kim, Min Soo; Cho, Won Ju

    2011-07-01

    The single-transistor dynamic random-access memory (1T-DRAM) using a polycrystalline-silicon thin-film transistor (poly-Si TFT) was investigated. A 100-nm amorphous silicon thin film was deposited onto a 200-nm oxidized silicon wafer via low-pressure chemical vapor deposition (LPCVD), and the amorphous silicon layer was crystallized via eximer laser annealing (ELA) with a KrF source of 248 nm wavelength and 400 mJ/cm2 power. The fabricated capacitor less 1T-DRAM on the poly-Si TFT was evaluated via impact ionization and gate-induced drain leakage (GIDL) current programming. The device showed a clear memory margin between the "1" and "0" states, and as the channel length decreased, a floating body effect which induces a kink effect increases with high mobility. Furthermore, the GIDL current programming showed improved memory properties compared to the impact ionization method. Although the sensing margins and retention times in both program methods are commercially insufficient, it was confirmed the feasibility of the application of 1T-DRAM operation to TFTs.

  15. Fabrication of amorphous InGaZnO thin-film transistor-driven flexible thermal and pressure sensors

    NASA Astrophysics Data System (ADS)

    Park, Ick-Joon; Jeong, Chan-Yong; Cho, In-Tak; Lee, Jong-Ho; Cho, Eou-Sik; Kwon, Sang Jik; Kim, Bosul; Cheong, Woo-Seok; Song, Sang-Hun; Kwon, Hyuck-In

    2012-10-01

    In this work, we present the results concerning the use of amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) as a driving transistor of the flexible thermal and pressure sensors which are applicable to artificial skin systems. Although the a-IGZO TFT has been attracting much attention as a driving transistor of the next-generation flat panel displays, no study has been performed about the application of this new device to the driving transistor of the flexible sensors yet. The proposed thermal sensor pixel is composed of the series-connected a-IGZO TFT and ZnO-based thermistor fabricated on a polished metal foil, and the ZnO-based thermistor is replaced by the pressure sensitive rubber in the pressure sensor pixel. In both sensor pixels, the a-IGZO TFT acts as the driving transistor and the temperature/pressure-dependent resistance of the ZnO-based thermistor/pressure-sensitive rubber mainly determines the magnitude of the output currents. The fabricated a-IGZO TFT-driven flexible thermal sensor shows around a seven times increase in the output current as the temperature increases from 20 °C to 100 °C, and the a-IGZO TFT-driven flexible pressure sensors also exhibit high sensitivity under various pressure environments.

  16. Suppression of TFT leakage current effect on active matrix displays by employing a new circular switch

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hoon; Park, Hyun-Sang; Jeon, Jae-Hong; Han, Min-Koo

    2008-03-01

    We have proposed a new poly-Si TFT pixel, which can suppress TFT leakage current effect on active matrix organic diode (AMOLED) displays, by employing a new circular switching TFT and additional signal line for compensating the leakage current. When the leakage current of switching TFT is increased, the VGS of the current driving TFT in the proposed pixel is not altered by the variable data voltages due to the circular switching TFT. Our simulation results show that OLED current variation of the proposed pixel can be suppressed less than 3%, while that of conventional pixel exceeds 30%. The proposed pixel may be suitable to suppress the leakage current effect on AMOLED display.

  17. Thought Field Therapy (TFT) as a treatment for anxiety symptoms: a randomized controlled trial.

    PubMed

    Irgens, Audun; Dammen, Toril; Nysæter, Tor Erik; Hoffart, Asle

    2012-01-01

    To investigate whether thought field therapy (TFT) has an impact on anxiety symptoms in patients with a variety of anxiety disorders. Forty-five patients were randomized to either TFT (n = 23) or a waiting list (n = 22) condition. The wait-list group was reassessed and compared with the TFT group two and a half months after the initial evaluation. After the reassessment, the wait-list patients received treatment with TFT. All 45 patients were followed up one to two weeks after TFT treatment, as well as at three and 12 months after treatment. Patients with an anxiety disorder, mostly outpatients. TFT aims to influence the body's bioenergy field by tapping on specific points along energy meridians, thereby relieving anxiety and other symptoms. Symptom Checklist 90-Revised, Hospital Anxiety and Depression Scale, the Sheehan Disability Scale. Repeated-measures analysis of variance was used to compare the TFT and the wait-list group. The TFT group had a significantly better outcome on two measures of anxiety and one measure of function. Follow-up data for all patients taken together showed a significant decrease in all symptoms during the one to two weeks between the pretreatment and the post-treatment assessments. The significant improvement seen after treatment was maintained at the three- and 12-month assessments. The results suggest that TFT may have an enduring anxiety-reducing effect. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. A new LTPS TFT AC pixel circuit for an AMOLED

    NASA Astrophysics Data System (ADS)

    Yongwen, Zhang; Wenbin, Chen

    2013-01-01

    This work presents a new voltage programmed pixel circuit for an active-matrix organic light-emitting diode (AMOLED) display. The proposed pixel circuit consists of six low temperature polycrystalline silicon thin-film transistors (LTPS TFTs), one storage capacitor, and one OLED, and is verified by simulation work using HSPICE software. Besides effectively compensating for the threshold voltage variation of the driving TFT and OLED, the proposed pixel circuit offers an AC driving mode for the OLED, which can suppress the degradation of the OLED. Moreover, a high contrast ratio can be achieved by the proposed pixel circuit since the OLED does not emit any light except for the emission period.

  19. SciTech Connect

    Liu, Po-Tsun; Shieh, Han-Ping; Chou, Yi-Teh

    This work presents the electrical characteristics of the nitrogenated amorphous InGaZnO thin film transistor (a-IGZO:N TFT). The a-IGZO:N film acting as a channel layer of a thin film transistor (TFT) device was prepared by dc reactive sputter with a nitrogen and argon gas mixture at room temperature. Experimental results show that the in situ nitrogen incorporation to IGZO film can properly adjust the threshold voltage and enhance the ambient stability of a TFT device. Furthermore, the a-IGZO:N TFT has a 44% increase in the carrier mobility and electrical reliability and uniformity also progress obviously while comparing with those not implementingmore » a nitrogen doping process.« less

  20. Mode of action of trifluorothymidine (TFT) against DNA replication and repair enzymes.

    PubMed

    Suzuki, Norihiko; Emura, Tomohiro; Fukushima, Masakazu

    2011-07-01

    Trifluorothymidine (TFT) is well known to be converted to TFT-monophosphate by thymidine kinase and to inhibit thymidylate synthase. In addition, TFT-triphosphate (TFT-TP) is also incorporated into DNA, resulting in cytocidal effects. However, the precise mechanism of TFT-induced DNA damage is still unclear. Therefore, we investigated the modes of action of TFT against DNA replication and repair enzymes, as compared with those of 5FU and FdUrd. When HeLa cells were treated with TFT at a concentration of 1 µM (IC50 value), the concentration of TFT in the DNA was calculated as 62.2±0.9 pmol/1x106 cells for 4 h. On the other hand, following treatment of the cells with FdUrd (0.5 µM) and 5FU (10 µM) at their IC50 doses, the drug concentrations in the DNA were 7.53, and 0.17 pmol/1 x 10⁶ cells for 4 h, respectively. These results show the markedly greater degree of incorporation of TFT into the DNA of the HeLa cells compared with that of 5FU (approximately more than 300-fold for 4 h) or FdUrd (approximately more than 8-fold for 4 h). The primer extension assay demonstrated that TFT-TP was also incorporated into the T-sites of the growing DNA strand, however, it competed only weakly with thymidine triphosphate. The DNA glycosylase assay was performed using commercially available DNA glycosylase and fractionated HeLa cell extracts obtained by gel filtration. There was no detectable excision of the TFT pairing to adenine by uracil DNA glycosylase (UDG), thymine DNA glycosylase (TDG), methyl-CpG binding domain 4 (MBD4) or the fractionated HeLa cell extracts, however, TDG and MBD4 were able to excise the TFT pairing to guanine. Additional data indicate that small-interfering RNA-mediated knockdown of TDG or MBD4 significantly increased the resistance to the cytotoxic effects of FdUrd, but not to that of TFT. These studies show the greater degree of incorporation of TFT into the DNA than that of 5FU or FdUrd, and that such a high degree of incorporation of TFT residues

  1. Transfer of stimulus control from a TFT to CRT screen.

    PubMed

    Railton, Renee Caron Richards; Foster, T Mary; Temple, William

    2010-10-01

    The use of television and computer screens for presenting stimuli to animals is increasing as it is non-invasive and can provide precise control over stimuli. Past studies have used cathode ray tube (CRT) screens; however, there is some evidence that these give different results to non-flickering thin film transistor (TFT) screens. Hens' critical flicker fusion frequency ranges between 80 and 90 Hz--above standard CRT screens. Thus, stimuli presented on CRT screens may appear distorted to hens. This study aimed to investigate whether changing the flicker rate of CRT screens altered hens' discrimination. Hens were trained (in a conditional discrimination) to discriminate between two stimuli on a TFT (flickerless) screen, and tested with the stimuli on a CRT screen at four flicker rates (60, 75, 85, and 100 Hz). The hens' accuracy generally decreased as the refresh rate of the CRT screen decreased. These results imply that the change in flicker rate changed the appearance of the stimuli enough to affect the hens' discrimination and stimulus control is disrupted when the stimuli appear to flicker. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  2. Optical residual stress measurement in TFT-LCD panels

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Chung; Sung, Po-Chi

    2017-06-01

    The residual stress of the glass substrate might be one of causes to produce the non-uniform light distribution defect, i.e. Mura, in thin film transistor-liquid crystal display (TFT-LCD) panels. Glass is a birefringent material with very low birefringence. Furthermore, the thinner and thinner thickness request from the market makes the traditional photoelasticity almost impossible to measure the residual stresses produced in thin glass plates. Recently, a low-level stress measurement method called transmissivity extremities theory of photoelasticity (TEToP) was successfully developed to measure the residual stress in glass plate. Besides, to measure the stress of the glass plate in the TFT-LCD panel whose rear surface may has different kinds of coatings, an advanced reflection photoelasticity was also developed. In this paper, three commercially available glass plates with 0.33mm nominal thickness and three glass circular disks with different coatings were inspected to verify the feasibility of the TEToP and the advanced reflection photoelasticity, respectively.

  3. Synthesis, Characterization and TFT Characteristics of Diketopyrrolopyrrole Based Copolymer.

    PubMed

    Bathula, Chinna; Jeong, Seunghoon; Chung, Jeyon; Kang, Youngjong

    2016-03-01

    A novel diketopyrrolopyrrole (DPP) based low band gap polymer, poly[4,8-bis(triisopropylsilylethynyl) benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-[2,5-di-hexyl-3,6-dithiophen-2-ylpyrrolo[3,4-c]pyrrole-1,4-dione] (PTIPSBDT-DPP) is synthesized by Stille polymerization for use in thin film transistor (TFTs). The new polymer contain extended aromatic π-conjugated segments alternating with the DPP units and are designed to increase the free energy for charge generation to overcome current limitations in photocurrent generation. In this study we describe the synthesis, thermal stability, optical, electrochemical properties and TFT characteristics.

  4. A cascade method for TFT-LCD defect detection

    NASA Astrophysics Data System (ADS)

    Yi, Songsong; Wu, Xiaojun; Yu, Zhiyang; Mo, Zhuoya

    2017-07-01

    In this paper, we propose a novel cascade detection algorithm which focuses on point and line defects on TFT-LCD. At the first step of the algorithm, we use the gray level difference of su-bimage to segment the abnormal area. The second step is based on phase only transform (POT) which corresponds to the Discrete Fourier Transform (DFT), normalized by the magnitude. It can remove regularities like texture and noise. After that, we improve the method of setting regions of interest (ROI) with the method of edge segmentation and polar transformation. The algorithm has outstanding performance in both computation speed and accuracy. It can solve most of the defect detections including dark point, light point, dark line, etc.

  5. Active-matrix OLED using 150°C a-Si TFT backplane built on flexible plastic substrate

    NASA Astrophysics Data System (ADS)

    Sarma, Kalluri R.; Chanley, Charles; Dodd, Sonia R.; Roush, Jared; Schmidt, John; Srdanov, Gordana; Stevenson, Matthew; Wessel, Ralf; Innocenzo, Jeffrey; Yu, Gang; O'Regan, Marie B.; MacDonald, W. A.; Eveson, R.; Long, Ke; Gleskova, Helena; Wagner, Sigurd; Sturm, James C.

    2003-09-01

    Flexible displays fabricated using plastic substrates have a potential for being very thin, light weight, highly rugged with greatly minimized propensity for breakage, roll-to-roll manufacturing and lower cost. The emerging OLED display media offers the advantage of being a solid state and rugged structure for flexible displays in addition to the many potential advantages of an AM OLED over the currently dominant AM LCD. The current high level of interest in flexible displays is facilitating the development of the required enabling technologies which include development of plastic substrates, low temperature active matrix device and backplane fabrication, and display packaging. In the following we will first discuss our development efforts in the PEN based plastic substrates, active matrix backplane technology, low temperature (150°C) a-Si TFT devices and an AM OLED test chip used for evaluating various candidate designs. We will then describe the design, fabrication and successful evaluation and demonstration of a 64x64 pixel AM OLED test display using a-Si TFT backplane fabricated at 150°C on the flexible plastic substrate.

  6. Technology and characterization of Thin-Film Transistors (TFTs) with a-IGZO semiconductor and high-k dielectric layer

    NASA Astrophysics Data System (ADS)

    Mroczyński, R.; Wachnicki, Ł.; Gierałtowska, S.

    2016-12-01

    In this work, we present the design of the technology and fabrication of TFTs with amorphous IGZO semiconductor and high-k gate dielectric layer in the form of hafnium oxide (HfOx). In the course of this work, the IGZO fabrication was optimized by means of Taguchi orthogonal tables approach in order to obtain an active semiconductor with reasonable high concentration of charge carriers, low roughness and relatively high mobility. The obtained Thin-Film Transistors can be characterized by very good electrical parameters, i.e., the effective mobility (μeff ≍ 12.8 cm2V-1s-1) significantly higher than that for a-Si TFTs (μeff ≍ 1 cm2V-1s-1). However, the value of sub-threshold swing (i.e., 640 mV/dec) points that the interfacial properties of IGZO/HfOx stack is characterized by high value of interface states density (Dit) which, in turn, demands further optimization for future applications of the demonstrated TFT structures.

  7. The novel thymidylate synthase inhibitor trifluorothymidine (TFT) and TRAIL synergistically eradicate non-small cell lung cancer cells.

    PubMed

    Azijli, Kaamar; van Roosmalen, Ingrid A M; Smit, Jorn; Pillai, Saravanan; Fukushima, Masakazu; de Jong, Steven; Peters, Godefridus J; Bijnsdorp, Irene V; Kruyt, Frank A E

    2014-06-01

    TRAIL, a tumor selective anticancer agent, may be used for the treatment of non-small cell lung cancer (NSCLC). However, TRAIL resistance is frequently encountered. Here, the combined use of TRAIL with trifluorothymidine (TFT), a thymidylate synthase inhibitor, was examined for sensitizing NSCLC cells to TRAIL. Interactions between TRAIL and TFT were studied in NSCLC cells using growth inhibition and apoptosis assays. Western blotting and flow cytometry were used to investigate underlying mechanisms. The combined treatment of TFT and TRAIL showed synergistic cytotoxicity in A549, H292, H322 and H460 cells. For synergistic activity, the sequence of administration was important; TFT treatment followed by TRAIL exposure did not show sensitization. Combined TFT and TRAIL treatment for 24 h followed by 48 h of TFT alone was synergistic in all cell lines, with combination index values below 0.9. The treatments affected cell cycle progression, with TRAIL inducing a G1 arrest and TFT, a G2/M arrest. TFT activated Chk2 and reduced Cdc25c levels known to cause G2/M arrest. TRAIL-induced caspase-dependent apoptosis was enhanced by TFT, whereas TFT alone mainly induced caspase-independent death. TFT increased the expression of p53 and p21/WAF1, and p53 was involved in the increase of TRAIL-R2 surface expression. TFT also caused downregulation of cFLIP and XIAP and increased Bax expression. TFT enhances TRAIL-induced apoptosis in NSCLC cells by sensitizing the apoptotic machinery at different levels in the TRAIL pathway. Our findings suggest a possible therapeutic benefit of the combined use of TFT and TRAIL in NSCLC.

  8. Dependence of Grain Size on the Performance of a Polysilicon Channel TFT for 3D NAND Flash Memory.

    PubMed

    Kim, Seung-Yoon; Park, Jong Kyung; Hwang, Wan Sik; Lee, Seung-Jun; Lee, Ki-Hong; Pyi, Seung Ho; Cho, Byung Jin

    2016-05-01

    We investigated the dependence of grain size on the performance of a polycrystalline silicon (poly-Si) channel TFT for application to 3D NAND Flash memory devices. It has been found that the device performance and memory characteristics are strongly affected by the grain size of the poly-Si channel. Higher on-state current, faster program speed, and poor endurance/reliability properties are observed when the poly-Si grain size is large. These are mainly attributed to the different local electric field induced by an oxide valley at the interface between the poly-Si channel and the gate oxide. In addition, the trap density at the gate oxide interface was successfully measured using a charge pumping method by the separation between the gate oxide interface traps and traps at the grain boundaries in the poly-Si channel. The poly-Si channel with larger grain size has lower interface trap density.

  9. High-Performance Visible-Blind Ultraviolet Photodetector Based on IGZO TFT Coupled with p-n Heterojunction.

    PubMed

    Yu, Jingjing; Javaid, Kashif; Liang, Lingyan; Wu, Weihua; Liang, Yu; Song, Anran; Zhang, Hongliang; Shi, Wen; Chang, Ting-Chang; Cao, Hongtao

    2018-03-07

    A visible-blind ultraviolet (UV) photodetector was designed based on a three-terminal electronic device of thin-film transistor (TFT) coupled with two-terminal p-n junction optoelectronic device, in hope of combining the beauties of both of the devices together. Upon the uncovered back-channel surface of amorphous indium-gallium-zinc-oxide (IGZO) TFT, we fabricated PEDOT:PSS/SnO x /IGZO heterojunction structure, through which the formation of a p-n junction and directional carrier transfer of photogenerated carriers were experimentally validated. As expected, the photoresponse characteristics of the newly designed photodetector, with a photoresponsivity of 984 A/W at a wavelength of 320 nm, a UV-visible rejection ratio up to 3.5 × 10 7 , and a specific detectivity up to 3.3 × 10 14 Jones, are not only competitive compared to the previous reports but also better than those of the pristine IGZO phototransistor. The hybrid photodetector could be operated in the off-current region with low supply voltages (<0.1 V) and ultralow power dissipation (<10 nW under illumination and ∼0.2 pW in the dark). Moreover, by applying a short positive gate pulse onto the gate, the annoying persistent photoconductivity presented in the wide band gap oxide-based devices could be suppressed conveniently, in hope of improving the response rate. With the terrific photoresponsivity along with the advantages of photodetecting pixel integration, the proposed phototransistor could be potentially used in high-performance visible-blind UV photodetector pixel arrays.

  10. Combined membrane bioreactor (MBR) and reverse osmosis (RO) system for thin-film transistor-liquid crystal display TFT-LCD, industrial wastewater recycling.

    PubMed

    Chen, T K; Chen, J N

    2004-01-01

    In TFT-LCD industry, water plays a variety of roles as a cleaning agent and reaction solvent. As good quality water is increasingly a scarce resource and wastewater treatment costs rises, the once-through use of industrial water is becoming uneconomical and environmentally unacceptable. Instead, recycling of TFT-LCD industrial wastewater is become more attractive from both an economic and environmental perspective. This research is mainly to explore the capacity of TFT-LCD industrial wastewater recycling by the process combined with membrane bioreactor and reverse osmosis processes. Over the whole experimental period, the MBR process achieved a satisfactory organic removal. The COD could be removed with an average of over 97.3%. For TOC and BOD5 items, the average removal efficiencies were 97.8 and 99.4% respectively. The stable effluent quality and satisfactory removal performance were ensured by the efficient interception performance of the UF membrane device incorporated with biological reactor. Moreover, the MBR effluent did not contain any suspended solids and the SDI value was under 3. After treatment of RO, excellent water quality of permeate were under 5 mg/l, 2.5 mg/l and 150 micros/cm for COD, TOC and conductivity respectively. The treated water can be recycled for the cooling tower make-up water or other purposes.

  11. Electrical Performance and Reliability Improvement of Amorphous-Indium-Gallium-Zinc-Oxide Thin-Film Transistors with HfO₂ Gate Dielectrics by CF₄ Plasma Treatment.

    PubMed

    Fan, Ching-Lin; Tseng, Fan-Ping; Tseng, Chiao-Yuan

    2018-05-17

    In this work, amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) with a HfO₂ gate insulator and CF₄ plasma treatment was demonstrated for the first time. Through the plasma treatment, both the electrical performance and reliability of the a-IGZO TFT with HfO₂ gate dielectric were improved. The carrier mobility significantly increased by 80.8%, from 30.2 cm²/V∙s (without treatment) to 54.6 cm²/V∙s (with CF₄ plasma treatment), which is due to the incorporated fluorine not only providing an extra electron to the IGZO, but also passivating the interface trap density. In addition, the reliability of the a-IGZO TFT with HfO₂ gate dielectric has also been improved by the CF₄ plasma treatment. By applying the CF₄ plasma treatment to the a-IGZO TFT, the hysteresis effect of the device has been improved and the device's immunity against moisture from the ambient atmosphere has been enhanced. It is believed that the CF₄ plasma treatment not only significantly improves the electrical performance of a-IGZO TFT with HfO₂ gate dielectric, but also enhances the device's reliability.

  12. Fabrication of InGaZnO Nonvolatile Memory Devices at Low Temperature of 150 degrees C for Applications in Flexible Memory Displays and Transparency Coating on Plastic Substrates.

    PubMed

    Hanh, Nguyen Hong; Jang, Kyungsoo; Yi, Junsin

    2016-05-01

    We directly deposited amorphous InGaZnO (a-IGZO) nonvolatile memory (NVM) devices with oxynitride-oxide-dioxide (OOO) stack structures on plastic substrate by a DC pulsed magnetron sputtering and inductively coupled plasma chemical vapor deposition (ICPCVD) system, using a low-temperature of 150 degrees C. The fabricated bottom gate a-IGZO NVM devices have a wide memory window with a low operating voltage during programming and erasing, due to an effective control of the gate dielectrics. In addition, after ten years, the memory device retains a memory window of over 73%, with a programming duration of only 1 ms. Moreover, the a-IGZO films show high optical transmittance of over 85%, and good uniformity with a root mean square (RMS) roughness of 0.26 nm. This film is a promising candidate to achieve flexible displays and transparency on plastic substrates because of the possibility of low-temperature deposition, and the high transparent properties of a-IGZO films. These results demonstrate that the a-IGZO NVM devices obtained at low-temperature have a suitable programming and erasing efficiency for data storage under low-voltage conditions, in combination with excellent charge retention characteristics, and thus show great potential application in flexible memory displays.

  13. Photometric and colorimetric measurements of CRT and TFT monitors for vision research

    NASA Astrophysics Data System (ADS)

    Klein, Johann; Zlatkova, Margarita; Lauritzen, Jan; Pierscionek, Barbara

    2013-08-01

    Visual displays have various limitations that can affect the results of vision research experiments. This study compares several characteristics of CRT (Hewlett Packard 7650) and TFT (LG Flatron L227 WT and Samsung 2233 RZ) monitors, including luminance and colour spatial homogeneity, luminance changes with viewing angle, contrast linearity and warm-up characteristics. In addition, the psychophysical performance in grating contrast sensitivity test for both CRT and TFT monitors was compared. The TFT monitors demonstrated spatial non-homogeneity ('mura') with up to 50% of luminance change across the screen and a more significant luminance viewing angle dependence compared with CRT. The chromaticity of the white point showed negligible variation across the screen. Both types of monitors required a warm-up time of the order of 60 min. Despite the physical differences between monitors, visual contrast sensitivity performance measured with the two types of monitors was similar using both static and flickering gratings.

  14. Prototype of IGZO-TFT preamplifier and analog counter for pixel detector

    NASA Astrophysics Data System (ADS)

    Shimazoe, K.; Koyama, A.; Takahashi, H.; Shindoh, T.; Miyoshi, H.

    2017-02-01

    IGZO-TFT (Indium Galium Zinc Oxide-Thin Film Transistor) is a promising technology for controlling large display areas and large area sensors because of its very low leakage current in the off state and relatively low cost. IGZO has been used as a switching gate for a large area flat-panel detector. The photon counting capability for X-ray medical imaging has been investigated and expected for low-dose exposure and material determination. Here the design and fabrication of a charge sensitive preamplifier and analog counter using IGZO-TFT processes and its performance are reported for the first time to be used for radiation photon counting applications.

  15. Sakai et al. is not an adequate demonstration of TFT effectiveness.

    PubMed

    Lohr, J M

    2001-10-01

    Sakai et al. (2001) report an uncontrolled case series of TFT treatments applied to a wide range of psychological complaints in a large health maintenance facility. They analyze verbal report measures of symptom severity and conclude that the specific treatment is effective for a wide range of psychological problems. A review of the theory and research on TFT efficacy indicates that the theoretical basis for the specific treatment is unfounded and that adequately controlled efficacy research has yet to be conducted. The authors' conclusions about effectiveness and applicability are not supported by either theory, prior research, or the findings of their clinical application. Copyright 2001 John Wiley & Sons, Inc.

  16. Electrical Performance and Reliability Improvement of Amorphous-Indium-Gallium-Zinc-Oxide Thin-Film Transistors with HfO2 Gate Dielectrics by CF4 Plasma Treatment

    PubMed Central

    Fan, Ching-Lin; Tseng, Fan-Ping; Tseng, Chiao-Yuan

    2018-01-01

    In this work, amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) with a HfO2 gate insulator and CF4 plasma treatment was demonstrated for the first time. Through the plasma treatment, both the electrical performance and reliability of the a-IGZO TFT with HfO2 gate dielectric were improved. The carrier mobility significantly increased by 80.8%, from 30.2 cm2/V∙s (without treatment) to 54.6 cm2/V∙s (with CF4 plasma treatment), which is due to the incorporated fluorine not only providing an extra electron to the IGZO, but also passivating the interface trap density. In addition, the reliability of the a-IGZO TFT with HfO2 gate dielectric has also been improved by the CF4 plasma treatment. By applying the CF4 plasma treatment to the a-IGZO TFT, the hysteresis effect of the device has been improved and the device’s immunity against moisture from the ambient atmosphere has been enhanced. It is believed that the CF4 plasma treatment not only significantly improves the electrical performance of a-IGZO TFT with HfO2 gate dielectric, but also enhances the device’s reliability. PMID:29772767

  17. Use of thin film transistor liquid crystal display (TFT-LCD) waste glass in the production of ceramic tiles.

    PubMed

    Lin, Kae-Long

    2007-09-05

    In this study, we employ the following operating conditions: varied pressure (25 kgf/cm(2)), sintering temperature (900-1200 degrees C), sintering time (6h), percentage of thin film transistor liquid crystal display (TFT-LCD) waste glass by weight (0-50%) and temperature rising at a rate of 5 degrees C/min, to fabricate clay tiles. The sintering characteristics of the clay blended with TFT-LCD waste glass tiles are examined to evaluate the feasibility of the reuse of TFT-LCD waste glass. TFT-LCD waste glass contains large amounts of glass. The TCLP leaching concentrations all met the ROC EPAs current regulatory thresholds. The addition of TFT-LCD waste glass to the mixture, increased the apparent weight loss. The incorporation of 50% TFT-LCD waste glass resulted in a significant increase in the porosity ratio of the specimens compared to the porosity ratio of the ceramic tile containing TFT-LCD waste glass. The main constituent in both the clay tile and the clay with TFT-LCD waste glass samples is quartz. Increasing the temperature resulted in an increase in the flexural strength and resistance to abrasion in the tiles. The porosity ratio decreases as shrinkage increases. The relation between the porosity ratio and the hardness of the tiles used in the study is also shown.

  18. In-TFT-Array-Process Micro Defect Inspection Using Nonlinear Principal Component Analysis

    PubMed Central

    Liu, Yi-Hung; Wang, Chi-Kai; Ting, Yung; Lin, Wei-Zhi; Kang, Zhi-Hao; Chen, Ching-Shun; Hwang, Jih-Shang

    2009-01-01

    Defect inspection plays a critical role in thin film transistor liquid crystal display (TFT-LCD) manufacture, and has received much attention in the field of automatic optical inspection (AOI). Previously, most focus was put on the problems of macro-scale Mura-defect detection in cell process, but it has recently been found that the defects which substantially influence the yield rate of LCD panels are actually those in the TFT array process, which is the first process in TFT-LCD manufacturing. Defect inspection in TFT array process is therefore considered a difficult task. This paper presents a novel inspection scheme based on kernel principal component analysis (KPCA) algorithm, which is a nonlinear version of the well-known PCA algorithm. The inspection scheme can not only detect the defects from the images captured from the surface of LCD panels, but also recognize the types of the detected defects automatically. Results, based on real images provided by a LCD manufacturer in Taiwan, indicate that the KPCA-based defect inspection scheme is able to achieve a defect detection rate of over 99% and a high defect classification rate of over 96% when the imbalanced support vector machine (ISVM) with 2-norm soft margin is employed as the classifier. More importantly, the inspection time is less than 1 s per input image. PMID:20057957

  19. In-TFT-array-process micro defect inspection using nonlinear principal component analysis.

    PubMed

    Liu, Yi-Hung; Wang, Chi-Kai; Ting, Yung; Lin, Wei-Zhi; Kang, Zhi-Hao; Chen, Ching-Shun; Hwang, Jih-Shang

    2009-11-20

    Defect inspection plays a critical role in thin film transistor liquid crystal display (TFT-LCD) manufacture, and has received much attention in the field of automatic optical inspection (AOI). Previously, most focus was put on the problems of macro-scale Mura-defect detection in cell process, but it has recently been found that the defects which substantially influence the yield rate of LCD panels are actually those in the TFT array process, which is the first process in TFT-LCD manufacturing. Defect inspection in TFT array process is therefore considered a difficult task. This paper presents a novel inspection scheme based on kernel principal component analysis (KPCA) algorithm, which is a nonlinear version of the well-known PCA algorithm. The inspection scheme can not only detect the defects from the images captured from the surface of LCD panels, but also recognize the types of the detected defects automatically. Results, based on real images provided by a LCD manufacturer in Taiwan, indicate that the KPCA-based defect inspection scheme is able to achieve a defect detection rate of over 99% and a high defect classification rate of over 96% when the imbalanced support vector machine (ISVM) with 2-norm soft margin is employed as the classifier. More importantly, the inspection time is less than 1 s per input image.

  20. Vitamin D insufficiency predicts time to first treatment (TFT) in early chronic lymphocytic leukemia (CLL).

    PubMed

    Molica, Stefano; Digiesi, Giovanna; Antenucci, Anna; Levato, Luciano; Mirabelli, Rosanna; Molica, Matteo; Gentile, Massimo; Giannarelli, Diana; Sperduti, Isabella; Morabito, Fortunato; Conti, Laura

    2012-04-01

    Although vitamin D insufficiency is related to inferior prognosis in some cancers, limited data exist in hematologic malignancies. We evaluated the relationship between 25(OH)D serum levels and time to first treatment (TFT), a disease-specific end point, in 130 previously untreated Binet stage A chronic lymphocytic leukemia (CLL) patients. Measurement of 25(OH)D was performed by means of a direct, competitive chemiluminescence immunoassay using the DiaSorin LIAISON 25(OH)D TOTAL assay (DiaSorin, Inc., Stillwater, Minnesota). Overall, 41 patients (31.5%) had severe vitamin D insufficiency (<10 ng/mL), 66 (50.7%) had mild to moderate insufficiency (10-24 ng/mL), and 23 (17.6%) had 25(OH)D levels within the optimal range (25-80 ng/mL), with no relationship with between the season of sample collection and 25(OH)D level (P=0.188). A patient stratification according to these 3 groups led to significant difference in terms of TFT, with vitamin D insufficient patients having the shortest TFT (P=0.02). With respect to continuous 25(OH)D levels and clinical outcome, TFT was shorter as 25(OH)D decreased until a value of 13.5 ng/mL at which point the association of 25(OH)D and TFT remained constant. As a matter of fact, the 25(OH)D value of 13.5 ng/mL identified two patients subsets with different TFT risk (HR=1.91; 95% CI=1.06-3.44; P=0.03). In multivariate analysis the variable entering the model at a significant level were mutational status of IgVH (P<0.0001), serum thymidine kinase (P=0.02) and absolute lymphocyte count (P=0.03). Thus confirming the Mayo clinic experience, our data provide further evidence that 25(OH)D levels may be an important host factor influencing TFT of Binet stage A patients. Whether normalizing vitamin D levels may delay disease-progression of patients with early disease will require testing in future trials. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Extraction of sub-gap density of states via capacitance-voltage measurement for the erasing process in a TFT charge-trapping memory

    NASA Astrophysics Data System (ADS)

    Chiang, Yen-Chang; Hsiao, Yang-Hsuan; Li, Jeng-Ting; Chen, Jen-Sue

    2018-02-01

    Charge-trapping memories (CTMs) based on zinc tin oxide (ZTO) semiconductor thin-film transistors (TFTs) can be programmed by a positive gate voltage and erased by a negative gate voltage in conjunction with light illumination. To understand the mechanism involved, the sub-gap density of states associated with ionized oxygen vacancies in the ZTO active layer is extracted from optical response capacitance-voltage (C-V) measurements. The corresponding energy states of ionized oxygen vacancies are observed below the conduction band minimum at approximately 0.5-1.0 eV. From a comparison of the fitted oxygen vacancy concentration in the CTM-TFT after the light-bias erasing operation, it is found that the pristine-erased device contains more oxygen vacancies than the program-erased device because the trapped electrons in the programmed device are pulled into the active layer and neutralized by the oxygen vacancies that are present there.

  2. Lifetime prediction of InGaZnO thin film transistor for the application of display device and BEOL-transistors

    NASA Astrophysics Data System (ADS)

    Kim, Sang Min; Cho, Won Ju; Yu, Chong Gun; Park, Jong Tae

    2018-04-01

    In this work, the lifetime prediction models of amorphous InGaZnO thin film transistors (a-IGZO TFTs) were suggested for the application of display device and BEOL (Back End Of line) transistors with embedded a-IGZO TFTs. Four different types of test devices according to the active layer thickness, source/drain electrode materials and thermal treatments have been used to verify the suggested model. The device lifetimes under high gate bias stress and hot carrier stress were extracted through fittings of the stretched-exponential equation for threshold voltage shifts and the current estimation method for drain current degradations. Our suggested lifetime prediction models could be used in any kinds of structures of a-IGZO TFTs for the application of display device and BEOL transistors. The a-IGZO TFTs with embedded ITO local conducting layer under source/drain is better for BEOL transistor application and a-IGZO TFTs with InGaZnO thin film as source/drain electrodes may be better for the application of display devices. From 1983 to 1985, he was a Researcher at Gold-Star Semiconductor, Inc., Korea, where he worked on the development of SRAM. He joined the Department of Electronics Engineering, University of Incheon, Incheon, Korea, in 1987, where he is a Professor. As a visiting scientist at Massachusetts Institute of Technology, Cambridge, in 1991, he conducted research in hot carrier reliability of CMOS. As a visiting scholar at University of California, Davis, in 2001, he conducted research on the device structure of Nano-scale SOI CMOS. His recent interests are device structure and reliability of Nano-scale CMOS devices, flash memory, and thin film transistors.

  3. Manufacturing Methods and Engineering for TFT Addressed Display.

    DTIC Science & Technology

    1980-02-20

    type required for the Army’s DMD (Digital Message Device), based on an active-matrix addressed electroluminescent display previously developed by...electroluminescent phosphor as the light emitter, and finally packaging or encapsulation. Because of size limitations of the pilot manufacturing facility, the DMD ...display was designed as two identical halves, which were then to be made individually in the auto- mated machine and later assembled into a single DMD

  4. Biological treatment of thin-film transistor liquid crystal display (TFT-LCD) wastewater.

    PubMed

    Lei, C N; Whang, L M; Lin, H L

    2008-01-01

    The amount of pollutants produced during manufacturing processes of TFT-LCD (thin-film transistor liquid crystal display) substantially increases due to an increasing production of the opto-electronic industry in Taiwan. The total amount of wastewater from TFT-LCD manufacturing plants is expected to exceed 200,000 CMD in the near future. Typically, organic solvents used in TFT-LCD manufacturing processes account for more than 33% of the total TFT-LCD wastewater. The main components of these organic solvents are composed of the stripper (dimethyl sulphoxide (DMSO) and monoethanolamine (MEA)), developer (tetra-methyl ammonium hydroxide (TMAH)) and chelating agents. These compounds are recognized as non-or slow-biodegradable organic compounds and little information is available regarding their biological treatability. In this study, the performance of an A/O SBR (anoxic/oxic sequencing batch reactor) treating synthetic TFT-LCD wastewater was evaluated. The long-term experimental results indicated that the A/O SBR was able to achieve stable and satisfactory removal performance for DMSO, MEA and TMAH at influent concentrations of 430, 800, and 190 mg/L, respectively. The removal efficiencies for all three compounds examined were more than 99%. In addition, batch tests were conducted to study the degradation kinetics of DMSO, MEA, and TMAH under aerobic, anoxic, and anaerobic conditions, respectively. The organic substrate of batch tests conducted included 400 mg/L of DMSO, 250 mg/L of MEA, and 120 mg/L of TMAH. For DMSO, specific DMSO degradation rates under aerobic and anoxic conditions were both lower than 4 mg DMSO/g VSS-hr. Under anaerobic conditions, the specific DMSO degradation rate was estimated to be 14 mg DMSO/g VSS-hr, which was much higher than those obtained under aerobic and anoxic conditions. The optimum specific MEA and TMAH degradation rates were obtained under aerobic conditions with values of 26.5 mg MEA/g VSS-hr and 17.3 mg TMAH/g VSS

  5. Ambient effect on thermal stability of amorphous InGaZnO thin film transistors

    NASA Astrophysics Data System (ADS)

    Xu, Jianeng; Wu, Qi; Xu, Ling; Xie, Haiting; Liu, Guochao; Zhang, Lei; Dong, Chengyuan

    2016-12-01

    The thermal stability of amorphous InGaZnO thin film transistors (a-IGZO TFTs) with various ambient gases was investigated. The a-IGZO TFTs in air were more thermally stable than the devices in the ambient argon. Oxygen, rather than nitrogen and moisture, was responsible for this improvement. Furthermore, the thermal stability of the a-IGZO TFTs improved with the increasing oxygen content in the surrounding atmosphere. The related physical mechanism was examined, indicating that the higher ambient oxygen content induced more combinations of the oxygen vacancies and adsorbed oxygen ions in the a-IGZO, which resulted in the larger defect formation energy. This larger defect formation energy led to the smaller variation in the threshold voltage for the corresponding TFT devices.

  6. Effects of color combination and ambient illumination on visual perception time with TFT-LCD.

    PubMed

    Lin, Chin-Chiuan; Huang, Kuo-Chen

    2009-10-01

    An empirical study was carried out to examine the effects of color combination and ambient illumination on visual perception time using TFT-LCD. The effect of color combination was broken down into two subfactors, luminance contrast ratio and chromaticity contrast. Analysis indicated that the luminance contrast ratio and ambient illumination had significant, though small effects on visual perception. Visual perception time was better at high luminance contrast ratio than at low luminance contrast ratio. Visual perception time under normal ambient illumination was better than at other ambient illumination levels, although the stimulus color had a confounding effect on visual perception time. In general, visual perception time was better for the primary colors than the middle-point colors. Based on the results, normal ambient illumination level and high luminance contrast ratio seemed to be the optimal choice for design of workplace with video display terminals TFT-LCD.

  7. High performance MoS2 TFT using graphene contact first process

    NASA Astrophysics Data System (ADS)

    Chang Chien, Chih-Shiang; Chang, Hsun-Ming; Lee, Wei-Ta; Tang, Ming-Ru; Wu, Chao-Hsin; Lee, Si-Chen

    2017-08-01

    An ohmic contact of graphene/MoS2 heterostructure is determined by using ultraviolet photoelectron spectroscopy (UPS). Since graphene shows a great potential to replace metal contact, a direct comparison of Cr/Au contact and graphene contact on the MoS2 thin film transistor (TFT) is made. Different from metal contacts, the work function of graphene can be modulated. As a result, the subthreshold swing can be improved. And when VgTFT, a new method using graphene contact first and MoS2 layer last process that can avoid PMMA residue and high processing temperature is applied. MoS2 TFT using this method shows on/off current ratio up to 6×106 order of magnitude, high mobility of 116 cm2/V-sec, and subthreshold swing of only 0.515 V/dec.

  8. Recycling Strategy for Fabricating Low-Cost and High-Performance Carbon Nanotube TFT Devices.

    PubMed

    Yu, Xiaoqin; Liu, Dan; Kang, Lixing; Yang, Yi; Zhang, Xiaopin; Lv, Qianjin; Qiu, Song; Jin, Hehua; Song, Qijun; Zhang, Jin; Li, Qingwen

    2017-05-10

    High-purity semiconducting single-walled carbon nanotubes (s-SWNTs) can be obtained by conjugated polymer wrapping. However, further purification of sorted s-SWNTs and high costs of raw materials are still challenges to practical applications. It is inevitable that a lot of polymers still cover the surface of s-SWNTs after separation, and the cost of the polymer is relatively higher than that of SWNTs. Here, we demonstrated a facile isolated process to improve the quality of s-SWNT solutions and films significantly. Compared with the untreated s-SWNTs, the contact resistance between the s-SWNT and the electrode is reduced by 20 times, and the thin-film transistors show 300% enhancement of current density. In this process, most of the polymers can be recycled and reused directly without any purification, which can greatly decrease the cost for s-SWNT separation. The results presented herein demonstrate a new scalable and low-cost approach for large-scale application of s-SWNTs in the electronics industry.

  9. SciTech Connect

    Cho, Byungsu; Samsung Display Co. Ltd., Tangjeong, Chungcheongnam-Do 336-741; Choi, Yonghyuk

    We demonstrate an enhanced electrical stability through a Ti oxide (TiO{sub x}) layer on the amorphous InGaZnO (a-IGZO) back-channel; this layer acts as a surface polarity modifier. Ultrathin Ti deposited on the a-IGZO existed as a TiO{sub x} thin film, resulting in oxygen cross-binding with a-IGZO surface. The electrical properties of a-IGZO thin film transistors (TFTs) with TiO{sub x} depend on the surface polarity change and electronic band structure evolution. This result indicates that TiO{sub x} on the back-channel serves as not only a passivation layer protecting the channel from ambient molecules or process variables but also a control layermore » of TFT device parameters.« less

  10. Highly stable field emission from ZnO nanowire field emitters controlled by an amorphous indium–gallium–zinc-oxide thin film transistor

    NASA Astrophysics Data System (ADS)

    Li, Xiaojie; Wang, Ying; Zhang, Zhipeng; Ou, Hai; She, Juncong; Deng, Shaozhi; Xu, Ningsheng; Chen, Jun

    2018-04-01

    Lowering the driving voltage and improving the stability of nanowire field emitters are essential for them to be applied in devices. In this study the characteristics of zinc oxide (ZnO) nanowire field emitter arrays (FEAs) controlled by an amorphous indium–gallium–zinc-oxide thin film transistor (a-IGZO TFT) were studied. A low driving voltage along with stabilization of the field emission current were achieved. Modulation of field emission currents up to three orders of magnitude was achieved at a gate voltage of 0–32 V for a constant anode voltage. Additionally, a-IGZO TFT control can dramatically reduce the emission current fluctuation (i.e., from 46.11 to 1.79% at an emission current of ∼3.7 µA). Both the a-IGZO TFT and ZnO nanowire FEAs were prepared on glass substrates in our research, demonstrating the feasibility of realizing large area a-IGZO TFT-controlled ZnO nanowire FEAs.

  11. High performance flexible electronics for biomedical devices.

    PubMed

    Salvatore, Giovanni A; Munzenrieder, Niko; Zysset, Christoph; Kinkeldei, Thomas; Petti, Luisa; Troster, Gerhard

    2014-01-01

    Plastic electronics is soft, deformable and lightweight and it is suitable for the realization of devices which can form an intimate interface with the body, be implanted or integrated into textile for wearable and biomedical applications. Here, we present flexible electronics based on amorphous oxide semiconductors (a-IGZO) whose performance can achieve MHz frequency even when bent around hair. We developed an assembly technique to integrate complex electronic functionalities into textile while preserving the softness of the garment. All this and further developments can open up new opportunities in health monitoring, biotechnology and telemedicine.

  12. After-effects of TFT-LCD display polarity and display colour on the detection of low-contrast objects.

    PubMed

    Mayr, Susanne; Buchner, Axel

    2010-07-01

    Participants performed a word-non-word discrimination task within a car control display emulated on a thin film transistor liquid-crystal display (TFT-LCD). The task simulated an information read-out from a TFT-LCD-based instrument panel. Subsequently, participants performed a low-contrast object detection task that simulated the detection of objects during night-time driving. In experiment 1, words/non-words were presented black-on-white (positive polarity) or white-on-black (negative polarity). In experiments 2 and 3, display colour was additionally manipulated. A positive polarity advantage in the discrimination task was consistently observed. In contrast, positive displays interfered more than negative displays with subsequent detection. The detrimental after-effect of positive polarity displays was strong with white and blue, reduced with amber and absent with red displays. Subjective measures showed a preference for blue over red, but a slight advantage for amber over blue. Implications for TFT-LCD design are derived from the results. STATEMENT OF RELEVANCE: When using TFT-LCDs as car instrument panels, positive polarity red TFT-LCDs are very likely to lead to good instrument readability while at the same time minimising - relative to other colours - the negative effects of an illuminated display on low-contrast object detection during night-time driving.

  13. Study on the photoresponse of amorphous In-Ga-Zn-O and zinc oxynitride semiconductor devices by the extraction of sub-gap-state distribution and device simulation.

    PubMed

    Jang, Jun Tae; Park, Jozeph; Ahn, Byung Du; Kim, Dong Myong; Choi, Sung-Jin; Kim, Hyun-Suk; Kim, Dae Hwan

    2015-07-22

    Persistent photoconduction (PPC) is a phenomenon that limits the application of oxide semiconductor thin-film transistors (TFTs) in optical sensor-embedded displays. In the present work, a study on zinc oxynitride (ZnON) semiconductor TFTs based on the combination of experimental results and device simulation is presented. Devices incorporating ZnON semiconductors exhibit negligible PPC effects compared with amorphous In-Ga-Zn-O (a-IGZO) TFTs, and the difference between the two types of materials are examined by monochromatic photonic C-V spectroscopy (MPCVS). The latter method allows the estimation of the density of subgap states in the semiconductor, which may account for the different behavior of ZnON and IGZO materials with respect to illumination and the associated PPC. In the case of a-IGZO TFTs, the oxygen flow rate during the sputter deposition of a-IGZO is found to influence the amount of PPC. Small oxygen flow rates result in pronounced PPC, and large densities of valence band tail (VBT) states are observed in the corresponding devices. This implies a dependence of PPC on the amount of oxygen vacancies (VO). On the other hand, ZnON has a smaller bandgap than a-IGZO and contains a smaller density of VBT states over the entire range of its bandgap energy. Here, the concept of activation energy window (AEW) is introduced to explain the occurrence of PPC effects by photoinduced electron doping, which is likely to be associated with the formation of peroxides in the semiconductor. The analytical methodology presented in this report accounts well for the reduction of PPC in ZnON TFTs, and provides a quantitative tool for the systematic development of phototransistors for optical sensor-embedded interactive displays.

  14. Visual Costs of the Inhomogeneity of Luminance and Contrast by Viewing LCD-TFT Screens Off-Axis.

    PubMed

    Ziefle, Martina; Groeger, Thomas; Sommer, Dietmar

    2003-01-01

    In this study the anisotropic characteristics of TFT-LCD (Thin-Film-Transistor-Liquid Crystal Display) screens were examined. Anisotropy occurs as the distribution of luminance and contrast changes over the screen surface due to different viewing angles. On the basis of detailed photometric measurements the detection performance in a visual reaction task was measured in different viewing conditions. Viewing angle (0 degrees, frontal view; 30 degrees, off-axis; 50 degrees, off-axis) as well as ambient lighting (a dark or illuminated room) were varied. Reaction times and accuracy of detection performance were recorded. Results showed TFT's anisotropy to be a crucial factor deteriorating performance. With an increasing viewing angle performance decreased. It is concluded that TFT's anisotropy is a limiting factor for overall suitability and usefulness of this new display technology.

  15. Automatic Defect Detection for TFT-LCD Array Process Using Quasiconformal Kernel Support Vector Data Description

    PubMed Central

    Liu, Yi-Hung; Chen, Yan-Jen

    2011-01-01

    Defect detection has been considered an efficient way to increase the yield rate of panels in thin film transistor liquid crystal display (TFT-LCD) manufacturing. In this study we focus on the array process since it is the first and key process in TFT-LCD manufacturing. Various defects occur in the array process, and some of them could cause great damage to the LCD panels. Thus, how to design a method that can robustly detect defects from the images captured from the surface of LCD panels has become crucial. Previously, support vector data description (SVDD) has been successfully applied to LCD defect detection. However, its generalization performance is limited. In this paper, we propose a novel one-class machine learning method, called quasiconformal kernel SVDD (QK-SVDD) to address this issue. The QK-SVDD can significantly improve generalization performance of the traditional SVDD by introducing the quasiconformal transformation into a predefined kernel. Experimental results, carried out on real LCD images provided by an LCD manufacturer in Taiwan, indicate that the proposed QK-SVDD not only obtains a high defect detection rate of 96%, but also greatly improves generalization performance of SVDD. The improvement has shown to be over 30%. In addition, results also show that the QK-SVDD defect detector is able to accomplish the task of defect detection on an LCD image within 60 ms. PMID:22016625

  16. An integrated micro-manipulation and biosensing platform built in glass-based LTPS TFT technology

    NASA Astrophysics Data System (ADS)

    Chen, Lei-Guang; Wu, Dong-Yi; S-C Lu, Michael

    2012-09-01

    The glass-based low-temperature polycrystalline-silicon (LTPS) thin-film transistor (TFT) process, widely known for making liquid crystal displays, is utilized in this work to realize a fully integrated, microbead-based micro-manipulation and biosensing platform. The operation utilizes arrays of microelectrodes made of transparent iridium tin oxide (ITO) to move the immobilized polystyrene microbeads to the sensor surface by dielectrophoresis (DEP). Detection of remaining microbeads after a specific antigen/antibody reaction is accomplished by photo-detectors under the transparent electrodes. It was found that microbeads can be driven successfully by the 30 × 30 µm2 microelectrodes separated by 10 µm with no more than 6 Vp-p, which is compatible with the operating range of thin-film transistors. Microbeads immobilized with antimouse immunoglobulin (IgG) and prostate-specific antigen (PSA) antibody were successfully detected after specific binding, illustrating the potential of LTPS TFT microarrays for more versatile biosensing applications.

  17. Automatic defect detection for TFT-LCD array process using quasiconformal kernel support vector data description.

    PubMed

    Liu, Yi-Hung; Chen, Yan-Jen

    2011-01-01

    Defect detection has been considered an efficient way to increase the yield rate of panels in thin film transistor liquid crystal display (TFT-LCD) manufacturing. In this study we focus on the array process since it is the first and key process in TFT-LCD manufacturing. Various defects occur in the array process, and some of them could cause great damage to the LCD panels. Thus, how to design a method that can robustly detect defects from the images captured from the surface of LCD panels has become crucial. Previously, support vector data description (SVDD) has been successfully applied to LCD defect detection. However, its generalization performance is limited. In this paper, we propose a novel one-class machine learning method, called quasiconformal kernel SVDD (QK-SVDD) to address this issue. The QK-SVDD can significantly improve generalization performance of the traditional SVDD by introducing the quasiconformal transformation into a predefined kernel. Experimental results, carried out on real LCD images provided by an LCD manufacturer in Taiwan, indicate that the proposed QK-SVDD not only obtains a high defect detection rate of 96%, but also greatly improves generalization performance of SVDD. The improvement has shown to be over 30%. In addition, results also show that the QK-SVDD defect detector is able to accomplish the task of defect detection on an LCD image within 60 ms.

  18. New PMOS LTPS TFT pixel for AMOLED to suppress the hysteresis effect on OLED current by employing a reset voltage driving

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hoon; Park, Sang-Geun; Han, Sang-Myeon; Han, Min-Koo; Park, Kee-Chan

    2008-03-01

    New PMOS LTPS (low temperature polycrystalline silicon)-thin film transistor (TFT) pixel circuit, which can suppress an OLED current error caused by the hysteresis of LTPS-TFT for active matrix organic light emitting diode (AMOLED) display, is proposed and fabricated. The proposed pixel circuit employs a reset voltage driving so that the sweep direction of gate voltage in the current driving TFT is not altered by the gate voltage in the previous frame. Our experimental results show that OLED current error of the proposed pixel is successfully suppressed because a reset voltage can enable the starting gate voltage for a desired one not to be varied, while that of the conventional 2-TFT pixel exceeds over 15% due to the hysteresis of LTPS-TFT.

  19. Exposure to volatile organic compounds and kidney dysfunction in thin film transistor liquid crystal display (TFT-LCD) workers.

    PubMed

    Chang, Ta-Yuan; Huang, Kuei-Hung; Liu, Chiu-Shong; Shie, Ruei-Hao; Chao, Keh-Ping; Hsu, Wen-Hsin; Bao, Bo-Ying

    2010-06-15

    Many volatile organic compounds (VOCs) are emitted during the manufacturing of thin film transistor liquid crystal displays (TFT-LCDs), exposure to some of which has been reported to be associated with kidney dysfunction, but whether such an effect exists in TFT-LCD industry workers is unknown. This cross-sectional study aimed to investigate the association between exposure to VOCs and kidney dysfunction among TFT-LCD workers. The results showed that ethanol (1811.0+/-1740.4 ppb), acetone (669.0+/-561.0 ppb), isopropyl alcohol (187.0+/-205.3 ppb) and propylene glycol monomethyl ether acetate (PGMEA) (102.9+/-102.0 ppb) were the four dominant VOCs present in the workplace. The 63 array workers studied had a risk of kidney dysfunction 3.21-fold and 3.84-fold that of 61 cell workers and 18 module workers, respectively. Workers cumulatively exposed to a total level of isopropyl alcohol, PGMEA and propylene glycol monomethyl ether> or =324 ppb-year had a significantly higher risk of kidney dysfunction (adjusted OR=3.41, 95% CI=1.14-10.17) compared with those exposed to <25 ppb-year after adjustment for potential confounding factors. These findings indicated that array workers might be the group at greatest risk of kidney dysfunction within the TFT-LCD industry, and cumulative exposure to specific VOCs might be associated with kidney dysfunction. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.

  20. Influence of room lighting on grey-scale perception with a CRT-and a TFT monitor display.

    PubMed

    Haak, R; Wicht, M J; Hellmich, M; Nowak, G; Noack, M J

    2002-05-01

    To determine the influence of ambient lighting on grey-scale perception using a cathode-ray tube (CRT) and a thin film transistor (TFT) computer display. A cathode ray tube (Nokia XS 446) and a liquid crystal display (Panasonic LC 50S) were used at reduced room lighting (70 lux) and under conditions recommended for a dental operatory (1000 lux). Twenty-seven observers examined twice a modified SMPTE test pattern [0 to 255; 255 to 0] grey-scale values. The corresponding contrast differences were allocated to four ranges of grey levels (I: 0-63; II: 64-127; III: 128-191; IV: 192-255). The influences of monitor type, grey-scale range and illumination were evaluated by means of repeated measures analysis of variance. Detection of differences in monochromatic intensity was significantly earlier with reduced lighting (P<0.0001). When full ambient lighting was used, the TFT display was superior compared to the CRT monitor in ranges II and III (P<0.0001), whereas no differences could be detected for grey intensities between 0 and 63 (P=0.71) and between 192 and 255 (P=0.36). Background lighting hampers grey-scale perception on computer displays. In this study of one TFT and one CRT monitor, the TFT in full ambient lighting was associated with earlier detection of grey scale differences than CRT.

  1. Transfascial vaginal tape (TFT): a simple, safe and cost-effective procedure for stress urinary incontinence. A preliminary study.

    PubMed

    Foglia, Giovanni; Mistrangelo, Emanuela; Lijoi, Davide; Alessandri, Franco; Ragni, Nicola

    2007-07-01

    To analyse prospectively the effectiveness of a new simple, minimally invasive, and cost-effective technique for the treatment of female urinary stress incontinence: the transfascial vaginal tape (TFT). In a prospective study, we enrolled 45 women undergoing TFT with or without hysterectomy and/or another pelvic reconstructive procedure between 1st December 2003 and 31st December. TFT consists of a tension-free urethrosuspension using a sling located at the mid-urethral level and placed laterally in the endopelvic fascia previously perforated. Follow-up evaluations were established at 3 and 6 months and at 1 year after the operation. During each follow-up, women underwent cough stress test and they answered to the "Incontinence quality of life questionnaire" (I-QOL), to the Patient Global Impression of Severity (PGI-S) and of Improvement (PGI-I) questions. Thirty-nine patients (88.9%) had a follow-up examination 1 year after surgery. Of these, 30 (76.9%) were defined cured, 6 (15.4%) improved and 3 (7.7%) failed. TFT procedure can be considered a simple, safe and cost-effective procedure for the treatment of stress urinary incontinence and can be an alternative to tension-free vaginal tape or transobturator route for sub-urethral tape procedures.

  2. Treatment of TFT-LCD wastewater containing ethanolamine by fluidized-bed Fenton technology.

    PubMed

    Anotai, Jin; Chen, Chia-Min; Bellotindos, Luzvisminda M; Lu, Ming-Chun

    2012-06-01

    The objectives of this study are: (1) to determine the effect of pH, initial concentration of Fe(2+) and H(2)O(2) dosage on the removal efficiency of MEA by fluidized-bed Fenton process and Fenton process, (2) to determine the optimal conditions for the degradation of ethanolamine from TFT-LCD wastewater by fluidized-bed Fenton process. In the design of experiment, the Box-Behnken design was used to optimize the operating conditions. A removal efficiency of 98.9% for 5mM MEA was achieved after 2h under optimal conditions of pH3, [Fe(2+)]=5mM and [H(2)O(2)]=60mM. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Calibrated LCD/TFT stimulus presentation for visual psychophysics in fMRI.

    PubMed

    Strasburger, H; Wüstenberg, T; Jäncke, L

    2002-11-15

    Standard projection techniques using liquid crystal (LCD) or thin-film transistor (TFT) technology show drastic distortions in luminance and contrast characteristics across the screen and across grey levels. Common luminance measurement and calibration techniques are not applicable in the vicinity of MRI scanners. With the aid of a fibre optic, we measured screen luminances for the full space of screen position and image grey values and on that basis developed a compensation technique that involves both luminance homogenisation and position-dependent gamma correction. By the technique described, images displayed to a subject in functional MRI can be specified with high precision by a matrix of desired luminance values rather than by local grey value.

  4. AM OLED using a-Si TFT backplane on flexible plastic substrate

    NASA Astrophysics Data System (ADS)

    Sarma, Kalluri R.; Schmidt, John; Roush, Jerry; Chanley, Charles; Dodd, Sonia R.

    2004-09-01

    Amorphous silicon TFT technology continues to show promise for fabricating large area high resolution flexible AM OLED displays. This paper describes the recent progress in the flexible AM OLED development efforts at Honeywell since our publication in this conference's proceedings in 2003, describing the feasibility of fabricating a 64x64 pixel AM OLED on a flexible plastic substrate. In this paper we describe the design, and fabrication of a 160x160(x3) pixel AM OLED on a flexible plastic substrate with an equivalent 80cgpi resolution. Flexibility characteristics of the fabricated displays are discussed. Further advances and improvements required for extending the size and resolution of flexible AM OLED displays are discussed.

  5. TFT-Directed Electroplating of RGB Luminescent Films without a Vacuum or Mask toward a Full-Color AMOLED Pixel Matrix.

    PubMed

    Wang, Rong; Zhang, Donglian; Xiong, You; Zhou, Xuehong; Liu, Cao; Chen, Weifeng; Wu, Weijing; Zhou, Lei; Xu, Miao; Wang, Lei; Liu, Linlin; Peng, Junbiao; Ma, Yuguang; Cao, Yong

    2018-05-30

    The thin-film transistor (TFT) driving circuit is a separate electronic component embedded within the panel itself to switch the current for each pixel in active-matrix organic light-emitting diode displays. We reported a TFT-directed dye electroplating method to fabricate pixels; this would be a new method to deposit films on prepatterned electrode for organic full-color display, where TFT driving circuit provide a switching current signal to drive and direct dye depositing on selected RGB pixels. A prototype patterned color pixel matrix was achieved, as high-quality light-emitting films with uniform morphology, pure RGB chromaticity, and stable output.

  6. Water-Mediated Photochemical Treatments for Low-Temperature Passivation of Metal-Oxide Thin-Film Transistors.

    PubMed

    Heo, Jae Sang; Jo, Jeong-Wan; Kang, Jingu; Jeong, Chan-Yong; Jeong, Hu Young; Kim, Sung Kyu; Kim, Kwanpyo; Kwon, Hyuck-In; Kim, Jaekyun; Kim, Yong-Hoon; Kim, Myung-Gil; Park, Sung Kyu

    2016-04-27

    The low-temperature electrical passivation of an amorphous oxide semiconductor (AOS) thin-film transistor (TFT) is achieved by a deep ultraviolet (DUV) light irradiation-water treatment-DUV irradiation (DWD) method. The water treatment of the first DUV-annealed amorphous indium-gallium-zinc-oxide (a-IGZO) thin film is likely to induce the preferred adsorption of water molecules at the oxygen vacancies and leads to subsequent hydroxide formation in the bulk a-IGZO films. Although the water treatment initially degraded the electrical performance of the a-IGZO TFTs, the second DUV irradiation on the water-treated devices may enable a more complete metal-oxygen-metal lattice formation while maintaining low oxygen vacancies in the oxide films. Overall, the stable and dense metal-oxygen-metal (M-O-M) network formation could be easily achieved at low temperatures (below 150 °C). The successful passivation of structural imperfections in the a-IGZO TFTs, such as hydroxyl group (OH-) and oxygen vacancies, mainly results in the enhanced electrical performances of the DWD-processed a-IGZO TFTs (on/off current ratio of 8.65 × 10(9), subthreshold slope of 0.16 V/decade, an average mobility of >6.94 cm(2) V(-1) s(-1), and a bias stability of ΔVTH < 2.5 V), which show more than a 30% improvement over the simple DUV-treated a-IGZO TFTs.

  7. Multi-oxide active layer deposition using Applied Materials Pivot array coater for high-mobility metal oxide TFT

    NASA Astrophysics Data System (ADS)

    Park, Hyun Chan; Scheer, Evelyn; Witting, Karin; Hanika, Markus; Bender, Marcus; Hsu, Hao Chien; Yim, Dong Kil

    2015-11-01

    By controlling a thin indium tin oxide (ITO), indium zinc oxide interface layer between gate insulator and indium gallium zinc oxide (IGZO), the thin-film transistor (TFT) performance can reach higher mobility as conventional IGZO as well as superior stability. For large-area display application, Applied Materials static PVD array coater (Applied Materials GmbH & Co. KG, Alzenau, Germany) using rotary targets has been developed to enable uniform thin layer deposition in display industry. Unique magnet motion parameter optimization in Pivot sputtering coater is shown to provide very uniform thin ITO layer to reach TFT performance with high mobility, not only on small scale, but also on Gen8.5 (2500 × 2200 mm glass size) production system.

  8. Linking TFT-LCD wastewater treatment performance to microbial population abundance of Hyphomicrobium and Thiobacillus spp.

    PubMed

    Fukushima, Toshikazu; Whang, Liang-Ming; Chen, Po-Chun; Putri, Dyah Wulandari; Chang, Ming-Yu; Wu, Yi-Ju; Lee, Ya-Ching

    2013-08-01

    This study investigated the linkage between performance of two full-scale membrane bioreactor (MBR) systems treating thin-film transistor liquid crystal display (TFT-LCD) wastewater and the population dynamics of dimethylsulfoxide (DMSO)/dimethylsulfide (DMS) degrading bacteria. High DMSO degradation efficiencies were achieved in both MBRs, while the levels of nitrification inhibition due to DMS production from DMSO degradation were different in the two MBRs. The results of real-time PCR targeting on DMSO/DMS degrading populations, including Hyphomicrobium and Thiobacillus spp., indicated that a higher DMSO oxidation efficiency occurred at a higher Hyphomicrobium spp. abundance in the systems, suggesting that Hyphomicrobium spp. may be more important for complete DMSO oxidation to sulfate compared with Thiobacillus spp. Furthermore, Thiobacillus spp. was more abundant during poor nitrification, while Hyphomicrobium spp. was more abundant during good nitrification. It is suggested that microbial population of DMSO/DMS degrading bacteria is closely linking to both DMSO/DMS degradation efficiency and nitrification performance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Extended-gate-type IGZO electric-double-layer TFT immunosensor with high sensitivity and low operation voltage

    NASA Astrophysics Data System (ADS)

    Liang, Lingyan; Zhang, Shengnan; Wu, Weihua; Zhu, Liqiang; Xiao, Hui; Liu, Yanghui; Zhang, Hongliang; Javaid, Kashif; Cao, Hongtao

    2016-10-01

    An immunosensor is proposed based on the indium-gallium-zinc-oxide (IGZO) electric-double-layer thin-film transistor (EDL TFT) with a separating extended gate. The IGZO EDL TFT has a field-effect mobility of 24.5 cm2 V-1 s-1 and an operation voltage less than 1.5 V. The sensors exhibit the linear current response to label-free target immune molecule in the concentrations ranging from 1.6 to 368 × 10-15 g/ml with a detection limit of 1.6 × 10-15 g/ml (0.01 fM) under an ultralow operation voltage of 0.5 V. The IGZO TFT component demonstrates a consecutive assay stability and recyclability due to the unique structure with the separating extended gate. With the excellent electrical properties and the potential for plug-in-card-type multifunctional sensing, extended-gate-type IGZO EDL TFTs can be promising candidates for the development of a label-free biosensor for public health applications.

  10. Improved electrical performance and bias stability of solution-processed active bilayer structure of indium zinc oxide based TFT.

    PubMed

    Seo, Jin-Suk; Bae, Byeong-Soo

    2014-09-10

    We fabricated active single- and bilayer structure thin film transistors (TFTs) with aluminum or gallium doped (IZO:Al or IZO:Ga) and undoped indium zinc oxide (IZO) thin film layers using an aqueous solution process. The electrical performance and bias stability of these active single- and bilayer structure TFTs were investigated and compared to reveal the effects of Al/Gal doping and bilayer structure. The single-layer structure IZO TFT shows a high mobility of 19 cm(2)/V · s with a poor positive bias stability (PBS) of ΔVT + 3.4 V. However, Al/Ga doped in IZO TFT reduced mobility to 8.5-9.9 cm(2)/V · s but improved PBS to ΔVT + 1.6-1.7 V due to the reduction of oxygen vacancy. Thus, it is found the bilayer structure TFTs with a combination of bottom- and top-layer compositions modify both the mobility and bias stability of the TFTs to be optimized. The bilayer structure TFT with an IZO:X bottom layer possess high mobility and an IZO bottom layer improves the PBS.

  11. Quantitative evaluation of three advanced laparoscopic viewing technologies: a stereo endoscope, an image projection display, and a TFT display.

    PubMed

    Wentink, M; Jakimowicz, J J; Vos, L M; Meijer, D W; Wieringa, P A

    2002-08-01

    Compared to open surgery, minimally invasive surgery (MIS) relies heavily on advanced technology, such as endoscopic viewing systems and innovative instruments. The aim of the study was to objectively compare three technologically advanced laparoscopic viewing systems with the standard viewing system currently used in most Dutch hospitals. We evaluated the following advanced laparoscopic viewing systems: a Thin Film Transistor (TFT) display, a stereo endoscope, and an image projection display. The standard viewing system was comprised of a monocular endoscope and a high-resolution monitor. Task completion time served as the measure of performance. Eight surgeons with laparoscopic experience participated in the experiment. The average task time was significantly greater (p <0.05) with the stereo viewing system than with the standard viewing system. The average task times with the TFT display and the image projection display did not differ significantly from the standard viewing system. Although the stereo viewing system promises improved depth perception and the TFT and image projection displays are supposed to improve hand-eye coordination, none of these systems provided better task performance than the standard viewing system in this pelvi-trainer experiment.

  12. Supporting newly qualified dental therapists into practice: a longitudinal evaluation of a foundation training scheme for dental therapists (TFT).

    PubMed

    Bullock, A D; Barnes, E; Falcon, H C; Stearns, K

    2013-04-01

    Focused on the dental therapists foundation training (TFT) scheme run by the Postgraduate Dental Deaneries of Oxford and Wessex (NHS Education South Central - NESC) the objectives were (1) to evaluate the TFT 2010/11 scheme, identifying strengths, areas for development and drawing comparisons with the 2009 evaluation; and (2) to follow-up previous cohorts, reporting current work and retrospective reflections on the scheme. Data were collected from 2010/11 ('current') trainees (n = 10) through group discussion, questionnaire and portfolio extracts. Eleven past-trainees from 2008/09 and 2009/10 took part in a structured telephone interview or responded to questions via e-mail. Data from 2011 consolidated that collected earlier. The scheme was highly valued. Current participants thought the scheme should be mandatory and all past-participants would recommend it to others. Trainees attributed an increase in confidence and ability in their clinical skills to participation in TFT. Current trainees' concerns about finding therapy work were echoed in past-participants' post-scheme employment. At the point of qualification, trainees do not feel well-prepared for starting work as dental therapists. Opportunity to develop confidence and skills in a supportive environment is a key benefit of the scheme. Maintaining ability in the full range of duties requires continued use of skills and the opportunity to do this remains an ongoing challenge.

  13. Low temperature cured poly-siloxane passivation for highly reliable a-InGaZnO thin-film transistors

    NASA Astrophysics Data System (ADS)

    Yoshida, Naofumi; Bermundo, Juan Paolo; Ishikawa, Yasuaki; Nonaka, Toshiaki; Taniguchi, Katsuto; Uraoka, Yukiharu

    2018-05-01

    Low temperature processable passivation materials are necessary to fabricate highly reliable amorphous InGaZnO (a-IGZO) thin-film transistors (TFT) on organic substrates for flexible device applications. We investigated 3 types of poly-siloxane (Poly-SX) passivation layers fabricated by a solution process and cured at low temperatures (180 °C) for a-IGZO TFTs. This passivation layer greatly improves the stability of the a-IGZO device even after being subjected to positive (PBS) and negative bias stress (NBS). The field effect mobility (μ) of MePhQ504010 passivated on the TFT reached 8.34 cm2/Vs and had a small threshold voltage shift of 0.9 V after PBS, -0.8 V after NBS without the hump phenomenon. Furthermore, we analyzed the hydrogen and hydroxide states in the a-IGZO layer by secondary ion mass spectrometry and X-ray photoelectron spectroscopy to determine the cause of excellent electrical properties despite the curing performed at a low temperature. These results show the potential of the solution processed Poly-SX passivation layer for flexible devices.

  14. Microwave annealing effect for highly reliable biosensor: dual-gate ion-sensitive field-effect transistor using amorphous InGaZnO thin-film transistor.

    PubMed

    Lee, In-Kyu; Lee, Kwan Hyi; Lee, Seok; Cho, Won-Ju

    2014-12-24

    We used a microwave annealing process to fabricate a highly reliable biosensor using amorphous-InGaZnO (a-IGZO) thin-film transistors (TFTs), which usually experience threshold voltage instability. Compared with furnace-annealed a-IGZO TFTs, the microwave-annealed devices showed superior threshold voltage stability and performance, including a high field-effect mobility of 9.51 cm(2)/V·s, a low threshold voltage of 0.99 V, a good subthreshold slope of 135 mV/dec, and an outstanding on/off current ratio of 1.18 × 10(8). In conclusion, by using the microwave-annealed a-IGZO TFT as the transducer in an extended-gate ion-sensitive field-effect transistor biosensor, we developed a high-performance biosensor with excellent sensing properties in terms of pH sensitivity, reliability, and chemical stability.

  15. Enhancement of the Device Performance and the Stability with a Homojunction-structured Tungsten Indium Zinc Oxide Thin Film Transistor.

    PubMed

    Park, Hyun-Woo; Song, Aeran; Choi, Dukhyun; Kim, Hyung-Jun; Kwon, Jang-Yeon; Chung, Kwun-Bum

    2017-09-14

    Tungsten-indium-zinc-oxide thin-film transistors (WIZO-TFTs) were fabricated using a radio frequency (RF) co-sputtering system with two types of source/drain (S/D)-electrode material of conducting WIZO (homojunction structure) and the indium-tin oxide (ITO) (heterojunction structure) on the same WIZO active-channel layer. The electrical properties of the WIZO layers used in the S/D electrode and the active-channel layer were adjusted through oxygen partial pressure during the deposition process. To explain enhancements of the device performance and stability of the homojunction-structured WIZO-TFT, a systematic investigation of correlation between device performance and physical properties at the interface between the active layer and the S/D electrodes such as the contact resistance, surface/interfacial roughness, interfacial-trap density, and interfacial energy-level alignments was conducted. The homojunction-structured WIZO-TFT exhibited a lower contact resistance, smaller interfacial-trap density, and flatter interfacial roughness than the WIZO-TFT with the heterojunction structure. The 0.09 eV electron barrier of the homojunction-structured WIZO-TFT is lower than the 0.21 eV value that was obtained for the heterojunction-structured WIZO-TFT. This reduced electron barrier may be attributed to enhancements of device performance and stability, that are related to the carrier transport.

  16. Quantitative analysis of charge trapping and classification of sub-gap states in MoS2 TFT by pulse I-V method.

    PubMed

    Park, Junghak; Hur, Ji-Hyun; Jeon, Sanghun

    2018-04-27

    The threshold voltage instabilities and huge hysteresis of MoS 2 thin film transistors (TFTs) have raised concerns about their practical applicability in next-generation switching devices. These behaviors are associated with charge trapping, which stems from tunneling to the adjacent trap site, interfacial redox reaction and interface and/or bulk trap states. In this report, we present quantitative analysis on the electron charge trapping mechanism of MoS 2 TFT by fast pulse I-V method and the space charge limited current (SCLC) measurement. By adopting the fast pulse I-V method, we were able to obtain effective mobility. In addition, the origin of the trap states was identified by disassembling the sub-gap states into interface trap and bulk trap states by simple extraction analysis. These measurement methods and analyses enable not only quantitative extraction of various traps but also an understanding of the charge transport mechanism in MoS 2 TFTs. The fast I-V data and SCLC data obtained under various measurement temperatures and ambient show that electron transport to neighboring trap sites by tunneling is the main charge trapping mechanism in thin-MoS 2 TFTs. This implies that interfacial traps account for most of the total sub-gap states while the bulk trap contribution is negligible, at approximately 0.40% and 0.26% in air and vacuum ambient, respectively. Thus, control of the interface trap states is crucial to further improve the performance of devices with thin channels.

  17. Quantitative analysis of charge trapping and classification of sub-gap states in MoS2 TFT by pulse I-V method

    NASA Astrophysics Data System (ADS)

    Park, Junghak; Hur, Ji-Hyun; Jeon, Sanghun

    2018-04-01

    The threshold voltage instabilities and huge hysteresis of MoS2 thin film transistors (TFTs) have raised concerns about their practical applicability in next-generation switching devices. These behaviors are associated with charge trapping, which stems from tunneling to the adjacent trap site, interfacial redox reaction and interface and/or bulk trap states. In this report, we present quantitative analysis on the electron charge trapping mechanism of MoS2 TFT by fast pulse I-V method and the space charge limited current (SCLC) measurement. By adopting the fast pulse I-V method, we were able to obtain effective mobility. In addition, the origin of the trap states was identified by disassembling the sub-gap states into interface trap and bulk trap states by simple extraction analysis. These measurement methods and analyses enable not only quantitative extraction of various traps but also an understanding of the charge transport mechanism in MoS2 TFTs. The fast I-V data and SCLC data obtained under various measurement temperatures and ambient show that electron transport to neighboring trap sites by tunneling is the main charge trapping mechanism in thin-MoS2 TFTs. This implies that interfacial traps account for most of the total sub-gap states while the bulk trap contribution is negligible, at approximately 0.40% and 0.26% in air and vacuum ambient, respectively. Thus, control of the interface trap states is crucial to further improve the performance of devices with thin channels.

  18. Enhanced performance of amorphous In-Ga-Zn-O thin-film transistors using different metals for source/drain electrodes

    NASA Astrophysics Data System (ADS)

    Pyo, Ju-Young; Cho, Won-Ju

    2017-09-01

    In this paper, we propose an amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor (TFT) with off-planed source/drain electrodes. We applied different metals for the source/drain electrodes with Ni and Ti to control the work function as high and low. When we measured the configuration of Ni to drain and source to Ti, the a-IGZO TFT showed increased driving current, decreased leakage current, a high on/off current ratio, low subthreshold swing, and high mobility. In addition, we conducted a reliability test with a gate bias stress test at various temperatures. The results of the reliability test showed the Ni drain and Ti drain had an equivalent effective energy barrier height. Thus, we confirmed that the proposed off-planed structure improved the electrical characteristics of the fabricated devices without any degradation of characteristics. Through the a-IGZO TFT with different source/drain electrode metal engineering, we realized high-performance TFTs for next-generation display devices.

  19. Evaluation of thyroid stimulating hormone (TSH) alone as a first-line thyroid function test (TFT) in Papua New Guinea.

    PubMed

    Kende, M; Kandapu, S

    2002-01-01

    In the Port Moresby General Hospital, the Chemical Pathology Department assays both thyroid stimulating hormone (TSH) and free thyroxine (FT4) on all requests for a thyroid function test (TFT). The cost of assaying both tests is obviously higher than either test alone. In order to minimize the cost of a TFT we aimed to determine if TSH or FT4 alone as a first-line test would be adequate in assessing the thyroid hormone status of patients. We analyzed TFT records from January 1996 to May 2000 in the Port Moresby General Hospital. A total of 3089 TSH and 2867 FT4 were assayed at an annual reagent cost of Papua New Guinea kina 14,500. When TSH alone is used as a first-line test at the Port Moresby General Hospital, the biochemical status of 95% of patients will be appropriately categorized as euthyroidism, hypothyroidism or hyperthyroidism with only 5% discrepant (ie, normal TSH with abnormal FT4) results. In contrast, using FT4 alone as a first-line test correctly classifies only 84% of TFTs. Euthyroid status is observed in 50% of patients and FT4 assays on these samples will be excluded appropriately if a TSH-only protocol is adopted. Furthermore, we will save a quarter of the yearly cost of TFTs on reagents alone by performing TSH only. We conclude that TSH alone is an adequate first-line thyroid function test in Papua New Guinea and when it is normal no further FT4 test is necessary unless clinically indicated.

  20. The Tomato 14-3-3 Protein TFT4 Modulates H+ Efflux, Basipetal Auxin Transport, and the PKS5-J3 Pathway in the Root Growth Response to Alkaline Stress1[C][W

    PubMed Central

    Xu, Weifeng; Jia, Liguo; Shi, Weiming; Baluška, František; Kronzucker, Herbert J.; Liang, Jiansheng; Zhang, Jianhua

    2013-01-01

    Alkaline stress is a common environmental stress, in particular in salinized soils. Plant roots respond to a variety of soil stresses by regulating their growth, but the nature of the regulatory pathways engaged in the alkaline stress response (ASR) is not yet understood. Previous studies show that PIN-FORMED2, an auxin (indole-3-acetic acid [IAA]) efflux transporter, PKS5, a protein kinase, and DNAJ HOMOLOG3 (J3), a chaperone, play key roles in root H+ secretion by regulating plasma membrane (PM) H+-ATPases directly or by targeting 14-3-3 proteins. Here, we investigated the expression of all 14-3-3 gene family members (TOMATO 14-3-3 PROTEIN1 [TFT1]–TFT12) in tomato (Solanum lycopersicum) under ASR, showing the involvement of four of them, TFT1, TFT4, TFT6, and TFT7. When these genes were separately introduced into Arabidopsis (Arabidopsis thaliana) and overexpressed, only the growth of TFT4 overexpressors was significantly enhanced when compared with the wild type under stress. H+ efflux and the activity of PM H+-ATPase were significantly enhanced in the root tips of TFT4 overexpressors. Microarray analysis and pharmacological examination of the overexpressor and mutant plants revealed that overexpression of TFT4 maintains primary root elongation by modulating PM H+-ATPase-mediated H+ efflux and basipetal IAA transport in root tips under alkaline stress. TFT4 further plays important roles in the PKS5-J3 signaling pathway. Our study demonstrates that TFT4 acts as a regulator in the integration of H+ efflux, basipetal IAA transport, and the PKS5-J3 pathway in the ASR of roots and coordinates root apex responses to alkaline stress for the maintenance of primary root elongation. PMID:24134886

  1. Characteristics of Indium Tin Oxide (ITO) Nanoparticles Recovered by Lift-off Method from TFT-LCD Panel Scraps.

    PubMed

    Choi, Dongchul; Hong, Sung-Jei; Son, Yongkeun

    2014-11-27

    In this study, indium-tin-oxide (ITO) nanoparticles were simply recovered from the thin film transistor-liquid crystal display (TFT-LCD) panel scraps by means of lift-off method. This can be done by dissolving color filter (CF) layer which is located between ITO layer and glass substrate. In this way the ITO layer was easily lifted off the glass substrate of the panel scrap without panel crushing. Over 90% of the ITO on the TFT-LCD panel was recovered by using this method. After separating, the ITO was obtained as particle form and their characteristics were investigated. The recovered product appeared as aggregates of particles less than 100 nm in size. The weight ratio of In/Sn is very close to 91/9. XRD analysis showed that the ITO nanoparticles have well crystallized structures with (222) preferred orientation even after recovery. The method described in this paper could be applied to the industrial recovery business for large size LCD scraps from TV easily without crushing the glass substrate.

  2. Characteristics of Indium Tin Oxide (ITO) Nanoparticles Recovered by Lift-off Method from TFT-LCD Panel Scraps

    PubMed Central

    Choi, Dongchul; Hong, Sung-Jei; Son, Yongkeun

    2014-01-01

    In this study, indium-tin-oxide (ITO) nanoparticles were simply recovered from the thin film transistor-liquid crystal display (TFT-LCD) panel scraps by means of lift-off method. This can be done by dissolving color filter (CF) layer which is located between ITO layer and glass substrate. In this way the ITO layer was easily lifted off the glass substrate of the panel scrap without panel crushing. Over 90% of the ITO on the TFT-LCD panel was recovered by using this method. After separating, the ITO was obtained as particle form and their characteristics were investigated. The recovered product appeared as aggregates of particles less than 100 nm in size. The weight ratio of In/Sn is very close to 91/9. XRD analysis showed that the ITO nanoparticles have well crystallized structures with (222) preferred orientation even after recovery. The method described in this paper could be applied to the industrial recovery business for large size LCD scraps from TV easily without crushing the glass substrate. PMID:28788267

  3. Comparison of the detectability of high- and low-contrast details on a TFT screen and a CRT screen designed for radiologic diagnosis.

    PubMed

    Kotter, Elmar; Bley, Thorsten A; Saueressig, Ulrich; Fisch, Dagmar; Springer, Oliver; Winterer, Jan Torsten; Schaefer, Oliver; Langer, Mathias

    2003-11-01

    To evaluate the detection rate of fine details of a new thin-film transistor (TFT) grayscale monitor designed for radiologic diagnosis, compared with a type of cathode ray tube (CRT) screen used routinely for diagnostic radiology. Fifteen radiographs of a statistical phantom presenting low- and high-contrast details were obtained and read out with an Agfa ADC compact storage phosphor system. Each radiograph presented 60 high-density (high-contrast) and 60 low-density (low-contrast) test bodies. Approximately half the test bodies contained holes with different diameters. Observers were asked to detect the presence or absence of a hole in the test body on a 5-point confidence range. The total of 1800 test bodies was reviewed by 5 radiologists on the TFT monitor (20.8 inches; 1536 x 2048 pixels; maximum luminance, 650 cd/m2; contrast, 600:1) and the CRT monitor (21 inches; P45 Phosphor; 2048 x 2560 pixels operated at 1728 x 2304 pixels; maximum luminance, 600 cd/m2; contrast, 300:1). The data were analyzed by receiver-operator characteristic analysis. For high-contrast details, the mean area under the curve rated 0.9336 for the TFT monitor and 0.9312 for the CRT monitor. For low-contrast details, the mean area under the curve rated 0.9189 for the TFT monitor and 0.9224 for the CRT monitor. At P TFT screen performs as well as CRT monitors for the detection of fine details in both high- and low-contrast environments. Further studies with images derived from clinical routine are necessary before safely using TFT monitors in clinical practice.

  4. Identification and Deletion of Tft1, a Predicted Glycosyltransferase Necessary for Cell Wall β-1,3;1,4-Glucan Synthesis in Aspergillus fumigatus

    PubMed Central

    Samar, Danial; Kieler, Joshua B.; Klutts, J. Stacey

    2015-01-01

    Aspergillus fumigatus is an environmental mold that causes severe, often fatal invasive infections in immunocompromised patients. The search for new antifungal drug targets is critical, and the synthesis of the cell wall represents a potential area to find such a target. Embedded within the main β-1,3-glucan core of the A. fumigatus cell wall is a mixed linkage, β-D-(1,3;1,4)-glucan. The role of this molecule or how it is synthesized is unknown, though it comprises 10% of the glucans within the wall. While this is not a well-studied molecule in fungi, it has been studied in plants. Using the sequences of two plant mixed linkage glucan synthases, a single ortholog was identified in A. fumigatus (Tft1). A strain lacking this enzyme (tft1Δ) was generated along with revertant strains containing the native gene under the control of either the native or a strongly expressing promoter. Immunofluorescence staining with an antibody against β-(1,3;1,4)-glucan and biochemical quantification of this polysaccharide in the tft1Δ strain demonstrated complete loss of this molecule. Reintroduction of the gene into the knockout strain yielded reappearance in amounts that correlated with expected expression of the gene. The loss of Tft1 and mixed linkage glucan yielded no in vitro growth phenotype. However, there was a modest increase in virulence for the tft1Δ strain in a wax worm model. While the precise roles for β-(1,3;1,4)-glucan within A. fumigatus cell wall are still uncertain, it is clear that Tft1 plays a pivotal role in the biosynthesis of this cell wall polysaccharide. PMID:25723175

  5. Low-temperature sol-gel oxide TFT with a fluoropolymer dielectric to enhance the effective mobility at low operation voltage

    NASA Astrophysics Data System (ADS)

    Yu, Shang-Yu; Wang, Kuan-Hsun; Zan, Hsiao-Wen; Soppera, Olivier

    2017-06-01

    In this article, we propose a solution-processed high-performance amorphous indium-zinc oxide (a-IZO) thin-film transistor (TFT) gated with a fluoropolymer dielectric. Compared with a conventional IZO TFT with a silicon nitride dielectric, a fluoropolymer dielectric effectively reduces the operation voltage to less than 3 V and greatly increases the effective mobility 40-fold. We suggest that the dipole layer formed at the dielectric surface facilitates electron accumulation and induces the electric double-layer effect. The dipole-induced hysteresis effect is also investigated.

  6. Effect of hydrogen on the device performance and stability characteristics of amorphous InGaZnO thin-film transistors with a SiO2/SiNx/SiO2 buffer

    NASA Astrophysics Data System (ADS)

    Han, Ki-Lim; Ok, Kyung-Chul; Cho, Hyeon-Su; Oh, Saeroonter; Park, Jin-Seong

    2017-08-01

    We investigate the influence of the multi-layered buffer consisting of SiO2/SiNx/SiO2 on amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs). The multi-layered buffer inhibits permeation of water from flexible plastic substrates and prevents degradation of overlying organic layers. The a-IGZO TFTs with a multi-layered buffer suffer less positive bias temperature stress instability compared to the device with a single SiO2 buffer layer after annealing at 250 °C. Hydrogen from the SiNx layer diffuses into the active layer and reduces electron trapping at loosely bound oxygen defects near the SiO2/a-IGZO interface. Quantitative analysis shows that a hydrogen density of 1.85 × 1021 cm-3 is beneficial to reliability. However, the multi-layered buffer device annealed at 350 °C resulted in conductive characteristics due to the excess carrier concentration from the higher hydrogen density of 2.12 × 1021 cm-3.

  7. Zinc oxide nanowire networks for macroelectronic devices

    NASA Astrophysics Data System (ADS)

    Unalan, Husnu Emrah; Zhang, Yan; Hiralal, Pritesh; Dalal, Sharvari; Chu, Daping; Eda, Goki; Teo, K. B. K.; Chhowalla, Manish; Milne, William I.; Amaratunga, Gehan A. J.

    2009-04-01

    Highly transparent zinc oxide (ZnO) nanowire networks have been used as the active material in thin film transistors (TFTs) and complementary inverter devices. A systematic study on a range of networks of variable density and TFT channel length was performed. ZnO nanowire networks provide a less lithographically intense alternative to individual nanowire devices, are always semiconducting, and yield significantly higher mobilites than those achieved from currently used amorphous Si and organic TFTs. These results suggest that ZnO nanowire networks could be ideal for inexpensive large area electronics.

  8. Biological treatment of TMAH (tetra-methyl ammonium hydroxide) in a full-scale TFT-LCD wastewater treatment plant.

    PubMed

    Hu, Tai-Ho; Whang, Liang-Ming; Liu, Pao-Wen Grace; Hung, Yu-Ching; Chen, Hung-Wei; Lin, Li-Bin; Chen, Chia-Fu; Chen, Sheng-Kun; Hsu, Shu Fu; Shen, Wason; Fu, Ryan; Hsu, Romel

    2012-06-01

    This study evaluated biological treatment of TMAH in a full-scale methanogenic up-flow anaerobic sludge blanket (UASB) followed by an aerobic bioreactor. In general, the UASB was able to perform a satisfactory TMAH degradation efficiency, but the effluent COD of the aerobic bioreactor seemed to increase with an increased TMAH in the influent wastewater. The batch test results confirmed that the UASB sludge under methanogenic conditions would be favored over the aerobic ones for TMAH treatment due to its superb ability of handling high strength of TMAH-containing wastewaters. Based on batch experiments, inhibitory chemicals present in TFT-LCD wastewater like surfactants and sulfate should be avoided to secure a stable methanogenic TMAH degradation. Finally, molecular monitoring of Methanomethylovorans hollandica and Methanosarcina mazei in the full-scale plant, the dominant methanogens in the UASB responsible for TMAH degradation, may be beneficial for a stable TMAH treatment performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Review of the potential of a wireless MEMS and TFT microsystems for the measurement of pressure in the GI tract.

    PubMed

    Arshak, A; Arshak, K; Waldron, D; Morris, D; Korostynska, O; Jafer, E; Lyons, G

    2005-06-01

    Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of MicroElectroMechanical Systems (MEMS) and thick film technology (TFT) for the fabrication of a wireless pressure sensing microsystem is presented. The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally the limitations of each technology are examined.

  10. Highly condensed fluorinated methacrylate hybrid material for transparent low-kappa passivation layer in LCD-TFT.

    PubMed

    Oh, Ji-Hoon; Kwak, Seung-Yeon; Yang, Seung-Cheol; Bae, Byeong-Soo

    2010-03-01

    Photocurable and highly condensed fluorinated methacrylate oligosiloxane, with a low dielectric constant (kappa = 2.54), was prepared by a nonhydrolytic sol-gel condensation reaction. The oligosiloxane resin was then spin-coated, photocured, and thermally baked in order to fabricate a fluorinated methacrylate hybrid material (FM hybrimer) thin film. This study investigated the application of this FM hybrimer film as a low-kappa passivation layer in LCD-based thin film transistors (TFT). It was found that a dielectric constant as low as kappa = 2.54 could be obtained, without introducing pores in the dense FM hybrimer films. This study compares FM hybrimer film characteristics with those required for passivation layers in LCD-TFTs, including thermal stability, optical transmittance, hydrophobicity, gap fill, and planarization effects as well as electrical insulation.

  11. New Product Development for Green and Low-Carbon Products—A Case Study of Taiwan's TFT-LCD Manufacturer

    NASA Astrophysics Data System (ADS)

    Lin, Chun-Yu; Lee, Amy H. I.

    2011-11-01

    Green supply chain has become an important topic these days due to pollution, global warming, extreme climatic events, etc. A green product is manufactured with the goal of reducing the damage to the environment and limiting the use of energy and other resources at any stage of its life, including raw materials, manufacture, use, and disposal. Carbon footprint is a good measure of the impact that a product has on the environment, especially in climate change, in the entire lifetime of the product. Carbon footprint is directly linked to CO2 emission; thus, the reduction of CO2 emission must be considered in the product life cycle. Although more and more researchers are working on the green supply chain management in the past few years, few have incorporated CO2 emission or carbon footprint into the green supply chain system. Therefore, this research aims to propose an integrated model for facilitating the new product development (NPD) for green and low-carbon products. In this research, a systematic model based on quality function deployment (QFD) is constructed for developing green and low-carbon products in a TFT-LCD manufacturer. Literature review and interviews with experts are done first to collect the factors for developing and manufacturing green and low-carbon products. Fuzzy Delphi method (FDM) is applied next to extract the important factors, and fuzzy interpretive structural modeling (FISM) is used subsequently to understand the relationships among factors. A house of quality (HOQ) for product planning is built last. The results shall provide important information for a TFT-LCD firm in designing a new product.

  12. Flexible organic TFT bio-signal amplifier using reliable chip component assembly process with conductive adhesive.

    PubMed

    Yoshimoto, Shusuke; Uemura, Takafumi; Akiyama, Mihoko; Ihara, Yoshihiro; Otake, Satoshi; Fujii, Tomoharu; Araki, Teppei; Sekitani, Tsuyoshi

    2017-07-01

    This paper presents a flexible organic thin-film transistor (OTFT) amplifier for bio-signal monitoring and presents the chip component assembly process. Using a conductive adhesive and a chip mounter, the chip components are mounted on a flexible film substrate, which has OTFT circuits. This study first investigates the assembly technique reliability for chip components on the flexible substrate. This study also specifically examines heart pulse wave monitoring conducted using the proposed flexible amplifier circuit and a flexible piezoelectric film. We connected the amplifier to a bluetooth device for a wearable device demonstration.

  13. Achieving high field-effect mobility in amorphous indium-gallium-zinc oxide by capping a strong reduction layer.

    PubMed

    Zan, Hsiao-Wen; Yeh, Chun-Cheng; Meng, Hsin-Fei; Tsai, Chuang-Chuang; Chen, Liang-Hao

    2012-07-10

    An effective approach to reduce defects and increase electron mobility in a-IGZO thin-film transistors (a-IGZO TFTs) is introduced. A strong reduction layer, calcium, is capped onto the back interface of a-IGZO TFT. After calcium capping, the effective electron mobility of a-IGZO TFT increases from 12 cm(2) V(-1) s(-1) to 160 cm(2) V(-1) s(-1). This high mobility is a new record, which implies that the proposed defect reduction effect is key to improve electron transport in oxide semiconductor materials. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Electrolyte gated TFT biosensors based on the Donnan's capacitance of anchored biomolecules

    NASA Astrophysics Data System (ADS)

    Manoli, Kyriaki; Palazzo, Gerardo; Macchia, Eleonora; Tiwari, Amber; Di Franco, Cinzia; Scamarcio, Gaetano; Favia, Pietro; Mallardi, Antonia; Torsi, Luisa

    2017-08-01

    Biodetection using electrolyte gated field effect transistors has been mainly correlated to charge modulated transduction. Therefore, such platforms are designed and studied for limited applications involving relatively small charged species and much care is taken in the operating conditions particularly pH and salt concentration (ionic strength). However, there are several reports suggesting that the device conductance can also be very sensitive towards variations in the capacitance coupling. Understanding the sensing mechanism is important for further exploitation of these promising sensors in broader range of applications. In this paper, we present a thorough and in depth study of a multilayer protein system coupled to an electrolyte gated transistor. It is demonstrated that detection associated to a binding event taking place at a distance of 30 nm far from the organic semiconductor-electrolyte interface is possible and the device conductance is dominated by Donnan's capacitance of anchored biomolecules.

  15. Tear secretion dysfunction among women workers engaged in light-on tests in the TFT-LCD industry.

    PubMed

    Su, Shih-Bin; Lu, Chih-Wei; Sheen, Jiunn-Woei; Kuo, Shu-Chun; Guo, How-Ran

    2006-12-16

    The TFT-LCD (thin film transistor liquid crystal display) industry is rapidly growing in Taiwan and many other countries. A large number of workers, mainly women, are employed in the light-on test process to detect the defects of products. At the light-on test workstation, the operator is generally exposed to low humidity (in the clean room environment), flashing light, and low ambient illumination for long working hours. Many workers complained about eye discomfort, and therefore we conducted a study to evaluate the tear secretion function of light-on test workers of a TFT-LCD company. We recruited workers engaged in light-on tests in the company during their periodical health examination. In addition to a questionnaire survey of demographic characteristics and ophthalmic symptoms, we evaluated the tear secretion function of both eyes of each participant using the Schirmer's lacrimal basal secretion test with anaesthesia. A participant with one or both eyes yielding abnormal test results was defined as a case of tear secretion dysfunction. During the study period, a total of 371 light-on test workers received the health examination at the clinic of the park, and 52 of them were excluded due to having ophthalmic diseases and other systemic diseases that may affect ophthalmic function. All the remaining 319 qualified workers agreed to participate in this study, and they were all females working by 4-shift rotations. The average age was 24.2 years old (standard deviation [SD] = 3.8), and the average employment duration was 13.6 months (SD = 5.7). Among the 11 ophthalmic symptoms evaluated, eye dryness was the most prevalent (prevalence = 43.3%). In addition, the prevalence of tear secretion dysfunction in at least one eye was 40.1% (128 cases), and contact lens users had an odds ratio of 1.73 (95% confidence interval = 1.02-2.94) in comparison with non-contact lens users. Comparing the Schirmer's test results of those who also participated in the screening in the

  16. Tear secretion dysfunction among women workers engaged in light-on tests in the TFT-LCD industry

    PubMed Central

    Su, Shih-Bin; Lu, Chih-Wei; Sheen, Jiunn-Woei; Kuo, Shu-Chun; Guo, How-Ran

    2006-01-01

    Background The TFT-LCD (thin film transistor liquid crystal display) industry is rapidly growing in Taiwan and many other countries. A large number of workers, mainly women, are employed in the light-on test process to detect the defects of products. At the light-on test workstation, the operator is generally exposed to low humidity (in the clean room environment), flashing light, and low ambient illumination for long working hours. Many workers complained about eye discomfort, and therefore we conducted a study to evaluate the tear secretion function of light-on test workers of a TFT-LCD company. Methods We recruited workers engaged in light-on tests in the company during their periodical health examination. In addition to a questionnaire survey of demographic characteristics and ophthalmic symptoms, we evaluated the tear secretion function of both eyes of each participant using the Schirmer's lacrimal basal secretion test with anaesthesia. A participant with one or both eyes yielding abnormal test results was defined as a case of tear secretion dysfunction. Results During the study period, a total of 371 light-on test workers received the health examination at the clinic of the park, and 52 of them were excluded due to having ophthalmic diseases and other systemic diseases that may affect ophthalmic function. All the remaining 319 qualified workers agreed to participate in this study, and they were all females working by 4-shift rotations. The average age was 24.2 years old (standard deviation [SD] = 3.8), and the average employment duration was 13.6 months (SD = 5.7). Among the 11 ophthalmic symptoms evaluated, eye dryness was the most prevalent (prevalence = 43.3%). In addition, the prevalence of tear secretion dysfunction in at least one eye was 40.1% (128 cases), and contact lens users had an odds ratio of 1.73 (95% confidence interval = 1.02–2.94) in comparison with non-contact lens users. Comparing the Schirmer's test results of those who also

  17. Present status of amorphous In-Ga-Zn-O thin-film transistors.

    PubMed

    Kamiya, Toshio; Nomura, Kenji; Hosono, Hideo

    2010-08-01

    The present status and recent research results on amorphous oxide semiconductors (AOSs) and their thin-film transistors (TFTs) are reviewed. AOSs represented by amorphous In-Ga-Zn-O (a-IGZO) are expected to be the channel material of TFTs in next-generation flat-panel displays because a-IGZO TFTs satisfy almost all the requirements for organic light-emitting-diode displays, large and fast liquid crystal and three-dimensional (3D) displays, which cannot be satisfied using conventional silicon and organic TFTs. The major insights of this review are summarized as follows. (i) Most device issues, such as uniformity, long-term stability against bias stress and TFT performance, are solved for a-IGZO TFTs. (ii) A sixth-generation (6G) process is demonstrated for 32″ and 37″ displays. (iii) An 8G sputtering apparatus and a sputtering target have been developed. (iv) The important effect of deep subgap states on illumination instability is revealed. (v) Illumination instability under negative bias has been intensively studied, and some mechanisms are proposed. (vi) Degradation mechanisms are classified into back-channel effects, the creation of traps at an interface and in the gate insulator, and the creation of donor states in annealed a-IGZO TFTs by the Joule heating; the creation of bulk defects should also be considered in the case of unannealed a-IGZO TFTs. (vii) Dense passivation layers improve the stability and photoresponse and are necessary for practical applications. (viii) Sufficient knowledge of electronic structures and electron transport in a-IGZO has been accumulated to construct device simulation models.

  18. Present status of amorphous In–Ga–Zn–O thin-film transistors

    PubMed Central

    Kamiya, Toshio; Nomura, Kenji; Hosono, Hideo

    2010-01-01

    The present status and recent research results on amorphous oxide semiconductors (AOSs) and their thin-film transistors (TFTs) are reviewed. AOSs represented by amorphous In–Ga–Zn–O (a-IGZO) are expected to be the channel material of TFTs in next-generation flat-panel displays because a-IGZO TFTs satisfy almost all the requirements for organic light-emitting-diode displays, large and fast liquid crystal and three-dimensional (3D) displays, which cannot be satisfied using conventional silicon and organic TFTs. The major insights of this review are summarized as follows. (i) Most device issues, such as uniformity, long-term stability against bias stress and TFT performance, are solved for a-IGZO TFTs. (ii) A sixth-generation (6G) process is demonstrated for 32″ and 37″ displays. (iii) An 8G sputtering apparatus and a sputtering target have been developed. (iv) The important effect of deep subgap states on illumination instability is revealed. (v) Illumination instability under negative bias has been intensively studied, and some mechanisms are proposed. (vi) Degradation mechanisms are classified into back-channel effects, the creation of traps at an interface and in the gate insulator, and the creation of donor states in annealed a-IGZO TFTs by the Joule heating; the creation of bulk defects should also be considered in the case of unannealed a-IGZO TFTs. (vii) Dense passivation layers improve the stability and photoresponse and are necessary for practical applications. (viii) Sufficient knowledge of electronic structures and electron transport in a-IGZO has been accumulated to construct device simulation models. PMID:27877346

  19. Poly-silicon TFT AM-OLED on thin flexible metal substrates

    NASA Astrophysics Data System (ADS)

    Afentakis, Themis; Hatalis, Miltiadis K.; Voutsas, Apostolos T.; Hartzell, John W.

    2003-05-01

    Thin metal foils present an excellent alternative to polymers for the fabrication of large area, flexible displays. Their main advantage spurs from their ability to withstand higher temperatures during processing; microelectronic fabrication at elevated temperatures offers the ability to utilize a variety of crystallization processes for the active layer of devices and thermally grown gate dielectrics. This can lead to high performance (high mobility, low threshold voltage) low cost and highly reliable thin film transistors. In some cases, the conductive substrate can also be used to provide power to the active devices, thus reducing layout complexity. This paper discusses the first successful attempt to design and fabricate a variety of active matrix organic light emitting diode displays on thin, flexible stainless steel foils. Different pixel architectures, such as two- and four-transistor implementations, and addressing modes, such as voltage- or current-driven schemese are examined. This work clearly demonstrates the advantages associated with the fabrication of OLED displays on thin metal foils, which - through roll-to-roll processing - can potentially result in revolutionizing today's display processing, leading to a new generation of low cost, high performance versatile display systems.

  20. Phenotypic behavior of C2C12 myoblasts upon expression of the dystrophy-related caveolin-3 P104L and TFT mutants.

    PubMed

    Fanzani, Alessandro; Stoppani, Elena; Gualandi, Laura; Giuliani, Roberta; Galbiati, Ferruccio; Rossi, Stefania; Fra, Anna; Preti, Augusto; Marchesini, Sergio

    2007-10-30

    Caveolin-3 (Cav-3) is the main scaffolding protein present in myofiber caveolae. We transfected C2C12 myoblasts with dominant negative forms of Cav-3, P104L or DeltaTFT, respectively, which cause the limb-girdle muscular dystrophy 1-C. Both these forms triggered Cav-3 loss during C2C12 cell differentiation. The P104L mutation reduced myofiber formation by impaired AKT signalling, accompanied by dramatic expression of the E3 ubiquitin ligase Atrogin. On the other hand, the DeltaTFT mutation triggered hypertrophic myotubes sustained by prolonged AKT activation, but independent of increased levels of follistatin and interleukin 4 expression. These data suggest that separated mutations within the same dystrophy-related gene may cause muscle degeneration through different mechanisms.

  1. Optimization of pulsed laser deposited ZnO thin-film growth parameters for thin-film transistors (TFT) application

    NASA Astrophysics Data System (ADS)

    Gupta, Manisha; Chowdhury, Fatema Rezwana; Barlage, Douglas; Tsui, Ying Yin

    2013-03-01

    In this work we present the optimization of zinc oxide (ZnO) film properties for a thin-film transistor (TFT) application. Thin films, 50±10 nm, of ZnO were deposited by Pulsed Laser Deposition (PLD) under a variety of growth conditions. The oxygen pressure, laser fluence, substrate temperature and annealing conditions were varied as a part of this study. Mobility and carrier concentration were the focus of the optimization. While room-temperature ZnO growths followed by air and oxygen annealing showed improvement in the (002) phase formation with a carrier concentration in the order of 1017-1018/cm3 with low mobility in the range of 0.01-0.1 cm2/V s, a Hall mobility of 8 cm2/V s and a carrier concentration of 5×1014/cm3 have been achieved on a relatively low temperature growth (250 °C) of ZnO. The low carrier concentration indicates that the number of defects have been reduced by a magnitude of nearly a 1000 as compared to the room-temperature annealed growths. Also, it was very clearly seen that for the (002) oriented films of ZnO a high mobility film is achieved.

  2. Nitrification performance and microbial ecology of nitrifying bacteria in a full-scale membrane bioreactor treating TFT-LCD wastewater.

    PubMed

    Whang, Liang-Ming; Wu, Yi-Ju; Lee, Ya-Chin; Chen, Hong-Wei; Fukushima, Toshikazu; Chang, Ming-Yu; Cheng, Sheng-Shung; Hsu, Shu-Fu; Chang, Cheng-Huey; Shen, Wason; Huang, Chung Kai; Fu, Ryan; Chang, Barkley

    2012-10-01

    This study investigated nitrification performance and nitrifying community in one full-scale membrane bioreactor (MBR) treating TFT-LCD wastewater. For the A/O MBR system treating monoethanolamine (MEA) and dimethyl sulfoxide (DMSO), no nitrification was observed, due presumably to high organic loading, high colloidal COD, low DO, and low hydraulic retention time (HRT) conditions. By including additional A/O or O/A tanks, the A/O/A/O MBR and the O/A/O MBR were able to perform successful nitrification. The real-time PCR results for quantification of nitrifying populations showed a high correlation to nitrification performance, and can be a good indicator of stable nitrification. Terminal restriction fragment length polymorphism (T-RFLP) results of functional gene, amoA, suggest that Nitrosomonas oligotropha-like AOB seemed to be important to a good nitrification in the MBR system. In the MBR system, Nitrobacter- and Nitrospira-like NOB were both abundant, but the low nitrite environment is likely to promote the growth of Nitrospira-like NOB. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. A neuro-fuzzy warning system for combating cybersickness in the elderly caused by the virtual environment on a TFT-LCD.

    PubMed

    Liu, Cheng-Li

    2009-05-01

    Only a few studies in the literature have focused on the effects of age on virtual environment (VE) sickness susceptibility and even less research was carried out focusing on the elderly. In general, the elderly usually browse VEs on a thin film transistor liquid crystal display (TFT-LCD) at home or somewhere, not a head-mounted display (HMD). While the TFT-LCD is used to present VEs, this set-up does not physically enclose the user. Therefore, this study investigated the factors that contribute to cybersickness among the elderly when immersed into a VE on TFT-LCD, including exposure durations, navigation rotating speeds and angle of inclination. Participants were elderly, with an average age of 69.5 years. The results of the first experiment showed that the rate of simulator sickness questionnaire (SSQ) scores increases significantly with navigational rotating speed and duration of exposure. However, the experimental data also showed that the rate of SSQ scores does not increase with the increase in angle of inclination. In applying these findings, the neuro-fuzzy technology was used to develop a neuro-fuzzy cybersickness-warning system integrating fuzzy logic reasoning and neural network learning. The contributing factors were navigational rotating speed and duration of exposure. The results of the second experiment showed that the proposed system can efficiently determine the level of cybersickness based on the associated subjective sickness estimates and combat cybersickness due to long exposure to a VE.

  4. Fabrication of amorphous IGZO thin film transistor using self-aligned imprint lithography with a sacrificial layer

    NASA Astrophysics Data System (ADS)

    Kim, Sung Jin; Kim, Hyung Tae; Choi, Jong Hoon; Chung, Ho Kyoon; Cho, Sung Min

    2018-04-01

    An amorphous indium-gallium-zinc-oxide (a-IGZO) thin film transistor (TFT) was fabricated by a self-aligned imprint lithography (SAIL) method with a sacrificial photoresist layer. The SAIL is a top-down method to fabricate a TFT using a three-dimensional multilayer etch mask having all pattern information for the TFT. The sacrificial layer was applied in the SAIL process for the purpose of removing the resin residues that were inevitably left when the etch mask was thinned by plasma etching. This work demonstrated that the a-IGZO TFT could be fabricated by the SAIL process with the sacrificial layer. Specifically, the simple fabrication process utilized in this study can be utilized for the TFT with a plasma-sensitive semiconductor such as the a-IGZO and further extended for the roll-to-roll TFT fabrication.

  5. Improvements in the bias illumination stability of amorphous InGaZnO thin-film transistors by using thermal treatments

    NASA Astrophysics Data System (ADS)

    Kim, Woo-Byung; Lee, Dong Keun; Ryu, Sang Ouk

    2014-07-01

    The a-IGZO deposited by using the rf sputtering method features a conductive or an insulator characteristic based on amount of oxygen. We demonstrated that a post-treatment affects the resistance patterns of particular-sized InGaZnO(IGZO) thin films in a-IGZO thin-film transistors (TFTs). Post-annealing shifted the driving voltage of a-IGZO TFT to positive or negative values, depending on the annealing temperatures. Post-annealing may introduce oxygen vacancies or desorbed oxygen in the IGZO thin film. The changed driving voltage of IGZO TFTs coincides with the shift of the resistance pattern of IGZO. The fabricated a-IGZO TFTs exhibited a field effect mobility of 6.2 cm2/Vs, an excellent subthreshold gate swing of 0.32 V/decade, and a high I on/off ratio of > 109. Under positive bias illumination stress (PBIS) and negative bias illumination stress (NBIS), after 3,600 seconds, the device threshold voltage shifted about 0.2 V and 0.3 V, respectively.

  6. Electric Field-aided Selective Activation for Indium-Gallium-Zinc-Oxide Thin Film Transistors

    NASA Astrophysics Data System (ADS)

    Lee, Heesoo; Chang, Ki Soo; Tak, Young Jun; Jung, Tae Soo; Park, Jeong Woo; Kim, Won-Gi; Chung, Jusung; Jeong, Chan Bae; Kim, Hyun Jae

    2016-10-01

    A new technique is proposed for the activation of low temperature amorphous InGaZnO thin film transistor (a-IGZO TFT) backplanes through application of a bias voltage and annealing at 130 °C simultaneously. In this ‘electrical activation’, the effects of annealing under bias are selectively focused in the channel region. Therefore, electrical activation can be an effective method for lower backplane processing temperatures from 280 °C to 130 °C. Devices fabricated with this method exhibit equivalent electrical properties to those of conventionally-fabricated samples. These results are analyzed electrically and thermodynamically using infrared microthermography. Various bias voltages are applied to the gate, source, and drain electrodes while samples are annealed at 130 °C for 1 hour. Without conventional high temperature annealing or electrical activation, current-voltage curves do not show transfer characteristics. However, electrically activated a-IGZO TFTs show superior electrical characteristics, comparable to the reference TFTs annealed at 280 °C for 1 hour. This effect is a result of the lower activation energy, and efficient transfer of electrical and thermal energy to a-IGZO TFTs. With this approach, superior low-temperature a-IGZO TFTs are fabricated successfully.

  7. Electric Field-aided Selective Activation for Indium-Gallium-Zinc-Oxide Thin Film Transistors

    PubMed Central

    Lee, Heesoo; Chang, Ki Soo; Tak, Young Jun; Jung, Tae Soo; Park, Jeong Woo; Kim, Won-Gi; Chung, Jusung; Jeong, Chan Bae; Kim, Hyun Jae

    2016-01-01

    A new technique is proposed for the activation of low temperature amorphous InGaZnO thin film transistor (a-IGZO TFT) backplanes through application of a bias voltage and annealing at 130 °C simultaneously. In this ‘electrical activation’, the effects of annealing under bias are selectively focused in the channel region. Therefore, electrical activation can be an effective method for lower backplane processing temperatures from 280 °C to 130 °C. Devices fabricated with this method exhibit equivalent electrical properties to those of conventionally-fabricated samples. These results are analyzed electrically and thermodynamically using infrared microthermography. Various bias voltages are applied to the gate, source, and drain electrodes while samples are annealed at 130 °C for 1 hour. Without conventional high temperature annealing or electrical activation, current-voltage curves do not show transfer characteristics. However, electrically activated a-IGZO TFTs show superior electrical characteristics, comparable to the reference TFTs annealed at 280 °C for 1 hour. This effect is a result of the lower activation energy, and efficient transfer of electrical and thermal energy to a-IGZO TFTs. With this approach, superior low-temperature a-IGZO TFTs are fabricated successfully. PMID:27725695

  8. Electric Field-aided Selective Activation for Indium-Gallium-Zinc-Oxide Thin Film Transistors.

    PubMed

    Lee, Heesoo; Chang, Ki Soo; Tak, Young Jun; Jung, Tae Soo; Park, Jeong Woo; Kim, Won-Gi; Chung, Jusung; Jeong, Chan Bae; Kim, Hyun Jae

    2016-10-11

    A new technique is proposed for the activation of low temperature amorphous InGaZnO thin film transistor (a-IGZO TFT) backplanes through application of a bias voltage and annealing at 130 °C simultaneously. In this 'electrical activation', the effects of annealing under bias are selectively focused in the channel region. Therefore, electrical activation can be an effective method for lower backplane processing temperatures from 280 °C to 130 °C. Devices fabricated with this method exhibit equivalent electrical properties to those of conventionally-fabricated samples. These results are analyzed electrically and thermodynamically using infrared microthermography. Various bias voltages are applied to the gate, source, and drain electrodes while samples are annealed at 130 °C for 1 hour. Without conventional high temperature annealing or electrical activation, current-voltage curves do not show transfer characteristics. However, electrically activated a-IGZO TFTs show superior electrical characteristics, comparable to the reference TFTs annealed at 280 °C for 1 hour. This effect is a result of the lower activation energy, and efficient transfer of electrical and thermal energy to a-IGZO TFTs. With this approach, superior low-temperature a-IGZO TFTs are fabricated successfully.

  9. Device and material characterization and analytic modeling of amorphous silicon thin film transistors

    NASA Astrophysics Data System (ADS)

    Slade, Holly Claudia

    Hydrogenated amorphous silicon thin film transistors (TFTs) are now well-established as switching elements for a variety of applications in the lucrative electronics market, such as active matrix liquid crystal displays, two-dimensional imagers, and position-sensitive radiation detectors. These applications necessitate the development of accurate characterization and simulation tools. The main goal of this work is the development of a semi- empirical, analytical model for the DC and AC operation of an amorphous silicon TFT for use in a manufacturing facility to improve yield and maintain process control. The model is physically-based, in order that the parameters scale with gate length and can be easily related back to the material and device properties. To accomplish this, extensive experimental data and 2D simulations are used to observe and quantify non- crystalline effects in the TFTs. In particular, due to the disorder in the amorphous network, localized energy states exist throughout the band gap and affect all regimes of TFT operation. These localized states trap most of the free charge, causing a gate-bias-dependent field effect mobility above threshold, a power-law dependence of the current on gate bias below threshold, very low leakage currents, and severe frequency dispersion of the TFT gate capacitance. Additional investigations of TFT instabilities reveal the importance of changes in the density of states and/or back channel conduction due to bias and thermal stress. In the above threshold regime, the model is similar to the crystalline MOSFET model, considering the drift component of free charge. This approach uses the field effect mobility to take into account the trap states and must utilize the correct definition of threshold voltage. In the below threshold regime, the density of deep states is taken into account. The leakage current is modeled empirically, and the parameters are temperature dependent to 150oC. The capacitance of the TFT can be

  10. Effect of defect creation and migration on hump characteristics of a-InGaZnO thin film transistors under long-term drain bias stress with light illumination

    NASA Astrophysics Data System (ADS)

    Cho, Yong-Jung; Kim, Woo-Sic; Lee, Yeol-Hyeong; Park, Jeong Ki; Kim, Geon Tae; Kim, Ohyun

    2018-06-01

    We investigated the mechanism of formation of the hump that occurs in the current-voltage I-V characteristics of amorphous InGaZnO (a-IGZO) thin film transistors (TFTs) that are exposed to long-term drain bias stress under illumination. Transfer characteristics showed two-stage degradation under the stress. At the beginning of the stress, the I-V characteristics shifted in the negative direction with a degradation of subthreshold slope, but the hump phenomenon developed over time in the I-V characteristics. The development of the hump was related to creation of defects, especially ionized oxygen vacancies which act as shallow donor-like states near the conduction-band minimum in a-IGZO. To further investigate the hump phenomenon we measured a capacitance-voltage C-V curve and performed two-dimensional device simulation. Stretched-out C-V for the gate-to-drain capacitance and simulated electric field distribution which exhibited large electric field near the drain side of TFT indicated that VO2+ were generated near the drain side of TFT, but the hump was not induced when VO2+ only existed near the drain side. Therefore, the degradation behavior under DBITS occurred because VO2+ were created near the drain side, then were migrated to the source side of the TFT.

  11. Biological treatment of thin-film transistor liquid crystal display (TFT-LCD) wastewater using aerobic and anoxic/oxic sequencing batch reactors.

    PubMed

    Lei, Chin-Nan; Whang, Liang-Ming; Chen, Po-Chun

    2010-09-01

    The amount of pollutants produced during manufacturing processes of thin-film transistor liquid crystal display (TFT-LCD) substantially increases due to an increasing production of the opto-electronic industry in Taiwan. This study presents the treatment performance of one aerobic and one anoxic/oxic (A/O) sequencing batch reactors (SBRs) treating synthetic TFT-LCD wastewater containing dimethyl sulfoxide (DMSO), monoethanolamine (MEA), and tetra-methyl ammonium hydroxide (TMAH). The long-term monitoring results for the aerobic and A/O SBRs demonstrate that stable biodegradation of DMSO, MEA, and TMAH can be achieved without any considerably adverse impacts. The ammonium released during MEA and TMAH degradation can also be completely oxidized to nitrate through nitrification in both SBRs. Batch studies on biodegradation rates for DMSO, MEA, and TMAH under anaerobic, anoxic, and aerobic conditions indicate that effective MEA degradation can be easily achieved under all three conditions examined, while efficient DMSO and TMAH degradation can be attained only under anaerobic and aerobic conditions, respectively. The potential odor problem caused by the formation of malodorous dimethyl sulfide from DMSO degradation under anaerobic conditions, however, requires insightful consideration in treating DMSO-containing wastewater. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  12. Evaluation of methanogenic treatment of TMAH (tetra-methyl ammonium hydroxide) in a full-scale TFT-LCD wastewater treatment process.

    PubMed

    Hu, T H; Whang, L M; Lei, C N; Chen, C F; Chiang, T Y; Lin, L B; Chen, H W; Liu, P W G; Cheng, S S

    2010-01-01

    This study evaluated TMAH biodegradation under methanogenic conditions. Under methanogenic conditions, a sludge from a full-scale UASB treating TFT-LCD wastewater was able to degrade 2,000 mg/L of TMAH within 10 h and attained a specific degradation rate of 19.2 mgTMAH/gVSS-h. Furthermore, several chemicals including some surfactants, DMSO, and sulfate were examined for their potential inhibitory effects on TMAH biodegradation under methanogenic conditions. The results indicated that surfactant S1 (up to 2%) and DMSO (up to 1,000 mg/L) presented negligible inhibitory effects on TMAH degradation, while surfactant S2 (0.2-1%) might inhibit methanogenic reaction without any TMAH degradation for 3-5 h. At sulfate concentrations higher than 300 mg/L, a complete inhibition of methanogenic reaction and TMAH biodegradation was observed. Results from cloning and sequencing of archaeal 16S rRNA gene fragments showed that Methanosarcina barkeri and Methanosarcina mazei were the dominant methanogens in the UASB treating TMAH-containing TFT-LCD wastewater.

  13. Metal Oxide Thin Film Transistors on Paper Substrate: Fabrication, Characterization, and Printing Process

    NASA Astrophysics Data System (ADS)

    Choi, Nack-Bong

    Flexible electronics is an emerging next-generation technology that offers many advantages such as light weight, durability, comfort, and flexibility. These unique features enable many new applications such as flexible display, flexible sensors, conformable electronics, and so forth. For decades, a variety of flexible substrates have been demonstrated for the application of flexible electronics. Most of them are plastic films and metal foils so far. For the fundamental device of flexible circuits, thin film transistors (TFTs) using poly silicon, amorphous silicon, metal oxide and organic semiconductor have been successfully demonstrated. Depending on application, low-cost and disposable flexible electronics will be required for convenience. Therefore it is important to study inexpensive substrates and to explore simple processes such as printing technology. In this thesis, paper is introduced as a new possible substrate for flexible electronics due to its low-cost and renewable property, and amorphous indium gallium zinc oxide (a-IGZO) TFTs are realized as the promising device on the paper substrate. The fabrication process and characterization of a-IGZO TFT on the paper substrate are discussed. a-IGZO TFTs using a polymer gate dielectric on the paper substrate demonstrate excellent performances with field effect mobility of ˜20 cm2 V-1 s-1, on/off current ratio of ˜106, and low leakage current, which show the enormous potential for flexible electronics application. In order to complement the n-channel a-IGZO TFTs and then enable complementary metal-oxide semiconductor (CMOS) circuit architectures, cuprous oxide is studied as a candidate material of p-channel oxide TFTs. In this thesis, a printing process is investigated as an alternative method for the fabrication of low-cost and disposable electronics. Among several printing methods, a modified offset roll printing that prints high resolution patterns is presented. A new method to fabricate a high resolution

  14. Optimizing operating parameters of a honeycomb zeolite rotor concentrator for processing TFT-LCD volatile organic compounds with competitive adsorption characteristics.

    PubMed

    Lin, Yu-Chih; Chang, Feng-Tang

    2009-05-30

    In this study, we attempted to enhance the removal efficiency of a honeycomb zeolite rotor concentrator (HZRC), operated at optimal parameters, for processing TFT-LCD volatile organic compounds (VOCs) with competitive adsorption characteristics. The results indicated that when the HZRC processed a VOCs stream of mixed compounds, compounds with a high boiling point take precedence in the adsorption process. In addition, existing compounds with a low boiling point adsorbed onto the HZRC were also displaced by the high-boiling-point compounds. In order to achieve optimal operating parameters for high VOCs removal efficiency, results suggested controlling the inlet velocity to <1.5m/s, reducing the concentration ratio to 8 times, increasing the desorption temperature to 200-225 degrees C, and setting the rotation speed to 6.5rpm.

  15. Effects of NH₄⁺ on Ce(IV) electro-regeneration in simulated and real spent TFT-LCD Cr-etching solutions.

    PubMed

    Chen, Te-San; Huang, Kuo-Lin; Lai, Yu-Chan; Kuo, Yi-Ming

    2012-08-15

    This investigation studies the electro-regeneration of Ce(IV) from Ce(III) in 4 M HNO(3) in the presence/absence of NH(4)(+) and real spent thin-film transistor liquid-crystal display (TFT-LCD) Cr-etching solutions. On Pt, at 2 A and 70 °C for 100 min, the Ce(IV) yield and apparent rate constant of Ce(III) oxidation in 4 M HNO(3) without NH(4)(+) were 100% and 5.54 × 10(-4) s(-1), respectively (and the activation energy was 13.1 kJ mol(-1)). Cyclic voltammetric and electrolytic measurements consistently support the noticeable inhibition by NH(4)(+) of Ce(III) oxidation and lowering of the Ce(IV) yield, respectively. The apparent diffusion coefficients for 0.2 and 0.02 M Ce(III) oxidation in 4 M HNO(3) that contained 0-0.6 M NH(4)(+) were (0.38-0.25) × 10(-5) and (1.6-0.9) × 10(-5) cm(2) s(-1), respectively. Because of combined effects of NH(4)(+) and anion impurities, the 100 min Ce(IV) yield of a real spent TFT-LCD Cr-etching solution (with [NH(4)(+)]/[Ce(III)] = 0.74 M/0.39 M) was 82%, lower than that of 4 M HNO(3) without NH(4)(+), but higher than those of 4 M HNO(3) that contained anion impurities with/without 0.4 M NH(4)(+). Copyright © 2012 Elsevier Ltd. All rights reserved.

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

    PubMed

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

    2016-05-09

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

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

    PubMed Central

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

    2016-01-01

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

  18. Amorphous InGaMgO Ultraviolet Photo-TFT with Ultrahigh Photosensitivity and Extremely Large Responsivity

    PubMed Central

    Zhang, Yiyu; Qian, Ling-Xuan; Wu, Zehan; Liu, Xingzhao

    2017-01-01

    Recently, amorphous InGaZnO ultraviolet photo thin-film transistors have exhibited great potential for application in future display technologies. Nevertheless, the transmittance of amorphous InGaZnO (~80%) is still not high enough, resulting in the relatively large sacrifice of aperture ratio for each sensor pixel. In this work, the ultraviolet photo thin-film transistor based on amorphous InGaMgO, which processes a larger bandgap and higher transmission compared to amorphous InGaZnO, was proposed and investigated. Furthermore, the effects of post-deposition annealing in oxygen on both the material and ultraviolet detection characteristics of amorphous InGaMgO were also comprehensively studied. It was found that oxygen post-deposition annealing can effectively reduce oxygen vacancies, leading to an optimized device performance, including lower dark current, higher sensitivity, and larger responsivity. We attributed it to the combined effect of the reduction in donor states and recombination centers, both of which are related to oxygen vacancies. As a result, the 240-min annealed device exhibited the lowest dark current of 1.7 × 10−10 A, the highest photosensitivity of 3.9 × 106, and the largest responsivity of 1.5 × 104 A/W. Therefore, our findings have revealed that amorphous InGaMgO photo thin-film transistors are a very promising alternative for UV detection, especially for application in touch-free interactive displays. PMID:28772529

  19. Amorphous InGaMgO Ultraviolet Photo-TFT with Ultrahigh Photosensitivity and Extremely Large Responsivity.

    PubMed

    Zhang, Yiyu; Qian, Ling-Xuan; Wu, Zehan; Liu, Xingzhao

    2017-02-13

    Recently, amorphous InGaZnO ultraviolet photo thin-film transistors have exhibited great potential for application in future display technologies. Nevertheless, the transmittance of amorphous InGaZnO (~80%) is still not high enough, resulting in the relatively large sacrifice of aperture ratio for each sensor pixel. In this work, the ultraviolet photo thin-film transistor based on amorphous InGaMgO, which processes a larger bandgap and higher transmission compared to amorphous InGaZnO, was proposed and investigated. Furthermore, the effects of post-deposition annealing in oxygen on both the material and ultraviolet detection characteristics of amorphous InGaMgO were also comprehensively studied. It was found that oxygen post-deposition annealing can effectively reduce oxygen vacancies, leading to an optimized device performance, including lower dark current, higher sensitivity, and larger responsivity. We attributed it to the combined effect of the reduction in donor states and recombination centers, both of which are related to oxygen vacancies. As a result, the 240-min annealed device exhibited the lowest dark current of 1.7 × 10 -10 A, the highest photosensitivity of 3.9 × 10⁶, and the largest responsivity of 1.5 × 10⁴ A/W. Therefore, our findings have revealed that amorphous InGaMgO photo thin-film transistors are a very promising alternative for UV detection, especially for application in touch-free interactive displays.

  20. A Simple Method for High-Performance, Solution-Processed, Amorphous ZrO2 Gate Insulator TFT with a High Concentration Precursor

    PubMed Central

    Cai, Wei; Zhu, Zhennan; Wei, Jinglin; Fang, Zhiqiang; Zheng, Zeke; Zhou, Shangxiong; Peng, Junbiao; Lu, Xubing

    2017-01-01

    Solution-processed high-k dielectric TFTs attract much attention since they cost relatively little and have a simple fabrication process. However, it is still a challenge to reduce the leakage of the current density of solution-processed dielectric TFTs. Here, a simple solution method is presented towards enhanced performance of ZrO2 films by intentionally increasing the concentration of precursor. The ZrO2 films not only exhibit a low leakage current density of 10−6 A/cm2 at 10 V and a breakdown field of 2.5 MV/cm, but also demonstrate a saturation mobility of 12.6 cm2·V−1·s−1 and a Ion/Ioff ratio of 106 in DC pulse sputtering IGZO-TFTs based on these films. Moreover, the underlying mechanism of influence of precursor concentration on film formation is presented. Higher concentration precursor results in a thicker film within same coating times with reduced ZrO2/IGZO interface defects and roughness. It shows the importance of thickness, roughness, and annealing temperature in solution-processed dielectric oxide TFT and provides an approach to precisely control solution-processed oxide films thickness. PMID:28825652

  1. A Simple Method for High-Performance, Solution-Processed, Amorphous ZrO₂ Gate Insulator TFT with a High Concentration Precursor.

    PubMed

    Cai, Wei; Zhu, Zhennan; Wei, Jinglin; Fang, Zhiqiang; Ning, Honglong; Zheng, Zeke; Zhou, Shangxiong; Yao, Rihui; Peng, Junbiao; Lu, Xubing

    2017-08-21

    Solution-processed high-k dielectric TFTs attract much attention since they cost relatively little and have a simple fabrication process. However, it is still a challenge to reduce the leakage of the current density of solution-processed dielectric TFTs. Here, a simple solution method is presented towards enhanced performance of ZrO₂ films by intentionally increasing the concentration of precursor. The ZrO₂ films not only exhibit a low leakage current density of 10 -6 A/cm² at 10 V and a breakdown field of 2.5 MV/cm, but also demonstrate a saturation mobility of 12.6 cm²·V -1 ·s -1 and a I on /I off ratio of 10⁶ in DC pulse sputtering IGZO-TFTs based on these films. Moreover, the underlying mechanism of influence of precursor concentration on film formation is presented. Higher concentration precursor results in a thicker film within same coating times with reduced ZrO₂/IGZO interface defects and roughness. It shows the importance of thickness, roughness, and annealing temperature in solution-processed dielectric oxide TFT and provides an approach to precisely control solution-processed oxide films thickness.

  2. Influences of Gate Bias and Light Stresses on Device Characteristics of High-Energy Electron-Beam-Irradiated Indium Gallium Zinc Oxide Based Thin Film Transistors

    NASA Astrophysics Data System (ADS)

    Yu, Kyeong Min; Moon, Hye Ji; Ryu, Min Ki; Cho, Kyoung Ik; Yun, Eui-Jung; Bae, Byung Seong

    2012-09-01

    Under white light illumination, amorphous indium-gallium-zinc oxide (a-IGZO)-based thin-film transistors (TFTs) showed a large negative shift of threshold voltage of more than -15 V depending on the process conditions. We investigated the influences of both gate bias and white light illumination on device properties of IGZO-based TFTs untreated and treated with high-energy electron beam irradiation (HEEBI). The TFTs were treated with HEEBI in air at room temperature (RT), electron beam energy of 0.8 MeV, and a dose of 1×1014 electrons/cm2. The HEEBI-treated TFTs showed an improved stability under negative bias illumination stress (NBIS) and positive bias illumination stress (PBIS) compared with non-HEEBI-treated TFTs, suggesting that the acceptor-like defects might be generated by HEEBI treatment near the valence band edge.

  3. Indium-gallium-zinc-oxide thin-film transistor with a planar split dual-gate structure

    NASA Astrophysics Data System (ADS)

    Liu, Yu-Rong; Liu, Jie; Song, Jia-Qi; Lai, Pui-To; Yao, Ruo-He

    2017-12-01

    An amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) with a planar split dual gate (PSDG) structure has been proposed, fabricated and characterized. Experimental results indicate that the two independent gates can provide dynamical control of device characteristics such as threshold voltage, sub-threshold swing, off-state current and saturation current. The transconductance extracted from the output characteristics of the device increases from 4.0 × 10-6S to 1.6 × 10-5S for a change of control gate voltage from -2 V to 2 V, and thus the device could be used in a variable-gain amplifier. A significant advantage of the PSDG structure is its flexibility in controlling the device performance according to the need of practical applications.

  4. Fluorine incorporation in solution-processed poly-siloxane passivation for highly reliable a-InGaZnO thin-film transistors

    NASA Astrophysics Data System (ADS)

    Yoshida, Naofumi; Bermundo, Juan Paolo; Ishikawa, Yasuaki; Nonaka, Toshiaki; Taniguchi, Katsuto; Uraoka, Yukiharu

    2018-03-01

    We investigated a fluorine-containing polysiloxane (Poly-SX) passivation layer fabricated by solution process for amorphous InGaZnO (a-IGZO) thin-film transistors (TFT). This passivation layer greatly improved the stability of the a-IGZO device even after being subjected to positive bias stress (PBS) and negative bias stress (NBS). The mobility (µ) of TFTs passivated by fluorine-containing Poly-SX increased by 31%-56% (10.50-12.54 cm2 V-1 s-1) compared with TFTs passivated by non-fluorinated Poly-SX (8.04 cm2 V-1 s-1). Increasing the amount of fluorine additives led to a higher µ in passivated TFTs. Aside from enhancing the performance, these passivation layers could increase the reliability of a-IGZO TFTs under PBS and NBS with a minimal threshold voltage shift (ΔV th) of up to  +0.2 V and  -0.1 V, respectively. Additionally, all TFTs passivated by the fluorinated passivation materials did not exhibit a hump effect after NBS. We also showed that fluorinated photosensitive Poly-SX, which can be fabricated without any dry etching process, had an effective passivation property. In this report, we demonstrated the photolithography of Poly-SX, and electrical properties of Poly-SX passivated TFTs, and analyzed the state of the a-IGZO layer to show the large potential of Poly-SX as an effective solution-processed passivation material.

  5. Nanometer-scale oxide thin film transistor with potential for high-density image sensor applications.

    PubMed

    Jeon, Sanghun; Park, Sungho; Song, Ihun; Hur, Ji-Hyun; Park, Jaechul; Kim, Hojung; Kim, Sunil; Kim, Sangwook; Yin, Huaxiang; Chung, U-In; Lee, Eunha; Kim, Changjung

    2011-01-01

    The integration of electronically active oxide components onto silicon circuits represents an innovative approach to improving the functionality of novel devices. Like most semiconductor devices, complementary-metal-oxide-semiconductor image sensors (CISs) have physical limitations when progressively scaled down to extremely small dimensions. In this paper, we propose a novel hybrid CIS architecture that is based on the combination of nanometer-scale amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) and a conventional Si photo diode (PD). With this approach, we aim to overcome the loss of quantum efficiency and image quality due to the continuous miniaturization of PDs. Specifically, the a-IGZO TFT with 180 nm gate length is probed to exhibit remarkable performance including low 1/f noise and high output gain, despite fabrication temperatures as low as 200 °C. In particular, excellent device performance is achieved using a double-layer gate dielectric (Al₂O₃/SiO₂) combined with a trapezoidal active region formed by a tailored etching process. A self-aligned top gate structure is adopted to ensure low parasitic capacitance. Lastly, three-dimensional (3D) process simulation tools are employed to optimize the four-pixel CIS structure. The results demonstrate how our stacked hybrid device could be the starting point for new device strategies in image sensor architectures. Furthermore, we expect the proposed approach to be applicable to a wide range of micro- and nanoelectronic devices and systems.

  6. Alumina nanoparticle/polymer nanocomposite dielectric for flexible amorphous indium-gallium-zinc oxide thin film transistors on plastic substrate with superior stability

    SciTech Connect

    Lai, Hsin-Cheng; Pei, Zingway, E-mail: zingway@dragon.nchu.edu.tw; Graduate Institute of Optoelectronic Engineering, National Chung Hsing University, Taichung 40227, Taiwan

    In this study, the Al{sub 2}O{sub 3} nanoparticles were incorporated into polymer as a nono-composite dielectric for used in a flexible amorphous Indium-Gallium-Zinc Oxide (a-IGZO) thin-film transistor (TFT) on a polyethylene naphthalate substrate by solution process. The process temperature was well below 100 °C. The a-IGZO TFT exhibit a mobility of 5.13 cm{sup 2}/V s on the flexible substrate. After bending at a radius of 4 mm (strain = 1.56%) for more than 100 times, the performance of this a-IGZO TFT was nearly unchanged. In addition, the electrical characteristics are less altered after positive gate bias stress at 10 V for 1500 s. Thus, this technology ismore » suitable for use in flexible displays.« less

  7. Reliable 6 PEP LTPS device for AMOLED's

    NASA Astrophysics Data System (ADS)

    Chou, Cheng-Wei; Wang, Pei-Yun; Hu, Chin-Wei; Chang, York; Chuang, Ching-Sang; Lin, Yusin

    2013-09-01

    This study presents a TFT structure which has less photo process and higher cost competitiveness in AMOLED display markets. A novel LTPS based 6 masks TFT structure for bottom emission AMOLED display is demonstrated in this paper. High field effect mobility (PMOS < 80 cm2/Vs ) and high reliability (PBTS △Vth< 0.02V @ 50oC VG=15V 10ks) was accomplished without the high temperature and rapid thermal annealing (RTA) activation process. Furthermore, a 14-inch AMOLED TV was achieved on the proposed 6-pep TFT backplane using the Gen. 3.5 mass production factory.

  8. Design of a handheld infrared imaging device based on uncooled infrared detector

    NASA Astrophysics Data System (ADS)

    Sun, Xianzhong; Li, Junwei; Zhang, Yazhou

    2017-02-01

    This paper, we introduced the system structure and operation principle of the device, and discussed our solutions for image data acquisition and storage, operating states and modes control and power management in detail. Besides, we proposed a algorithm of pseudo color for thermal image and applied it to the image processing module of the device. The thermal images can be real time displayed in a 1.8 inches TFT-LCD. The device has a compacted structure and can be held easily by one hand. It also has a good imaging performance with low power consumption, thermal sensitivity is less than 150mK. At last, we introduced one of its applications for fault diagnosis in electronic circuits, the test shows that: it's a good solution for fast fault detection.

  9. Modulation of the operational characteristics of amorphous In-Ga-Zn-O thin-film transistors by In2O3 nanoparticles

    NASA Astrophysics Data System (ADS)

    Lee, Min-Jung; Lee, Tae Il; Park, Jee Ho; Kim, Jung Han; Chae, Gee Sung; Jun, Myung Chul; Hwang, Yong Kee; Baik, Hong Koo; Lee, Woong; Myoung, Jae-Min

    2012-05-01

    The structure of thin-film transistors (TFTs) based on amorphous In-Ga-Zn-O (a-IGZO) was modified by spin coating a suspension of In2O3 nanoparticles on a SiO2/p++ Si layered wafer surface prior to the deposition of IGZO layer by room-temperature sputtering. The number of particles per unit area (surface density) of the In2O3 nanoparticles could be controlled by applying multiple spin coatings of the nanoparticle suspension. During the deposition of IGZO, the In2O3 nanoparticles initially located on the substrate surface migrated to the top of the IGZO layer indicating that they were not embedded within the IGZO layer, but they supplied In to the IGZO layer to increase the In concentration in the channel layer. As a result, the channel characteristics of the a-IGZO TFT were modulated so that the device showed an enhanced performance as compared with the reference device prepared without the nanoparticle treatment. Such an improved device performance is attributed to the nano-scale changes in the structure of (InO)n ordering assisted by increased In concentration in the amorphous channel layer.

  10. Photovoltaic device

    DOEpatents

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-09-01

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.

  11. Photovoltaic device

    DOEpatents

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-06-02

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

  12. Photovoltaic device

    DOEpatents

    Reese, Jason A; Keenihan, James R; Gaston, Ryan S; Kauffmann, Keith L; Langmaid, Joseph A; Lopez, Leonardo; Maak, Kevin D; Mills, Michael E; Ramesh, Narayan; Teli, Samar R

    2017-03-21

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

  13. Transparent indium-tin oxide/indium-gallium-zinc oxide Schottky diodes formed by gradient oxygen doping

    NASA Astrophysics Data System (ADS)

    Ho, Szuheng; Yu, Hyeonggeun; So, Franky

    2017-11-01

    Amorphous InGaZnO (a-IGZO) is promising for transparent electronics due to its high carrier mobility and optical transparency. However, most metal/a-IGZO junctions are ohmic due to the Fermi-level pinning at the interface, restricting their device applications. Here, we report that indium-tin oxide/a-IGZO Schottky diodes can be formed by gradient oxygen doping in the a-IGZO layer that would otherwise form an ohmic contact. Making use of back-to-back a-IGZO Schottky junctions, a transparent IGZO permeable metal-base transistor is also demonstrated with a high common-base gain.

  14. Investigations on the effects of electrode materials on the device characteristics of ferroelectric memory thin film transistors fabricated on flexible substrates

    NASA Astrophysics Data System (ADS)

    Yang, Ji-Hee; Yun, Da-Jeong; Seo, Gi-Ho; Kim, Seong-Min; Yoon, Myung-Han; Yoon, Sung-Min

    2018-03-01

    For flexible memory device applications, we propose memory thin-film transistors using an organic ferroelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] gate insulator and an amorphous In-Ga-Zn-O (a-IGZO) active channel. The effects of electrode materials and their deposition methods on the characteristics of memory devices exploiting the ferroelectric field effect were investigated for the proposed ferroelectric memory thin-film transistors (Fe-MTFTs) at flat and bending states. It was found that the plasma-induced sputtering deposition and mechanical brittleness of the indium-tin oxide (ITO) markedly degraded the ferroelectric-field-effect-driven memory window and bending characteristics of the Fe-MTFTs. The replacement of ITO electrodes with metal aluminum (Al) electrodes prepared by plasma-free thermal evaporation greatly enhanced the memory device characteristics even under bending conditions owing to their mechanical ductility. Furthermore, poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) was introduced to achieve robust bending performance under extreme mechanical stress. The Fe-MTFTs using PEDOT:PSS source/drain electrodes were successfully fabricated and showed the potential for use as flexible memory devices. The suitable choice of electrode materials employed for the Fe-MTFTs is concluded to be one of the most important control parameters for highly functional flexible Fe-MTFTs.

  15. Sealing device

    DOEpatents

    Garcia-Crespo, Andres Jose

    2013-12-10

    A sealing device for sealing a gap between a dovetail of a bucket assembly and a rotor wheel is disclosed. The sealing device includes a cover plate configured to cover the gap and a retention member protruding from the cover plate and configured to engage the dovetail. The sealing device provides a seal against the gap when the bucket assemply is subjected to a centrifugal force.

  16. Microfluidic Device

    NASA Technical Reports Server (NTRS)

    Tai, Yu-Chong (Inventor); Kasdan, Harvey L. (Inventor); Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor)

    2016-01-01

    Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

  17. Microfluidic Device

    NASA Technical Reports Server (NTRS)

    Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor); Kasdan, Harvey (Inventor); Tai, Yu-Chong (Inventor)

    2015-01-01

    Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

  18. Microfluidic Device

    NASA Technical Reports Server (NTRS)

    Tai, Yu-Chong (Inventor); Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor); Kasdan, Harvey L. (Inventor)

    2017-01-01

    Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

  19. Electrochromic devices

    DOEpatents

    Allemand, Pierre M.; Grimes, Randall F.; Ingle, Andrew R.; Cronin, John P.; Kennedy, Steve R.; Agrawal, Anoop; Boulton, Jonathan M.

    2001-01-01

    An electrochromic device is disclosed having a selective ion transport layer which separates an electrochemically active material from an electrolyte containing a redox active material. The devices are particularly useful as large area architectural and automotive glazings due to there reduced back reaction.

  20. PLASMA DEVICE

    DOEpatents

    Gow, J.D.; Wilcox, J.M.

    1961-12-26

    A device is designed for producing and confining highenergy plasma from which neutrons are generated in copious quantities. A rotating sheath of electrons is established in a radial electric field and axial magnetic field produced within the device. The electron sheath serves as a strong ionizing medium to gas introdueed thereto and also functions as an extremely effective heating mechanism to the resulting plasma. In addition, improved confinement of the plasma is obtained by ring magnetic mirror fields produced at the ends of the device. Such ring mirror fields are defined by the magnetic field lines at the ends of the device diverging radially outward from the axis of the device and thereafter converging at spatial annular surfaces disposed concentrically thereabout. (AFC)

  1. Low-temperature fabrication of an HfO2 passivation layer for amorphous indium-gallium-zinc oxide thin film transistors using a solution process.

    PubMed

    Hong, Seonghwan; Park, Sung Pyo; Kim, Yeong-Gyu; Kang, Byung Ha; Na, Jae Won; Kim, Hyun Jae

    2017-11-24

    We report low-temperature solution processing of hafnium oxide (HfO 2 ) passivation layers for amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs). At 150 °C, the hafnium chloride (HfCl 4 ) precursor readily hydrolyzed in deionized (DI) water and transformed into an HfO 2 film. The fabricated HfO 2 passivation layer prevented any interaction between the back surface of an a-IGZO TFT and ambient gas. Moreover, diffused Hf 4+ in the back-channel layer of the a-IGZO TFT reduced the oxygen vacancy, which is the origin of the electrical instability in a-IGZO TFTs. Consequently, the a-IGZO TFT with the HfO 2 passivation layer exhibited improved stability, showing a decrease in the threshold voltage shift from 4.83 to 1.68 V under a positive bias stress test conducted over 10,000 s.

  2. Catalytic devices

    DOEpatents

    Liu, Ming; Zhang, Xiang

    2018-01-23

    This disclosure provides systems, methods, and apparatus related to catalytic devices. In one aspect, a device includes a substrate, an electrically insulating layer disposed on the substrate, a layer of material disposed on the electrically insulating layer, and a catalyst disposed on the layer of material. The substrate comprises an electrically conductive material. The substrate and the layer of material are electrically coupled to one another and configured to have a voltage applied across them.

  3. Mobility Enhancement in Amorphous In-Ga-Zn-O Thin-Film Transistor by Induced Metallic in Nanoparticles and Cu Electrodes.

    PubMed

    Hu, Shiben; Ning, Honglong; Lu, Kuankuan; Fang, Zhiqiang; Li, Yuzhi; Yao, Rihui; Xu, Miao; Wang, Lei; Peng, Junbiao; Lu, Xubing

    2018-03-27

    In this work, we fabricated a high-mobility amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) based on alumina oxide (Al 2 O 3 ) passivation layer (PVL) and copper (Cu) source/drain electrodes (S/D). The mechanism of the high mobility for a-IGZO TFT was proposed and experimentally demonstrated. The conductivity of the channel layer was significantly improved due to the formation of metallic In nanoparticles on the back channel during Al 2 O 3 PVL sputtering. In addition, Ar atmosphere annealing induced the Schottky contact formation between the Cu S/D and the channel layer caused by Cu diffusion. In conjunction with high conductivity channel and Schottky contact, the a-IGZO TFT based on Cu S/D and Al 2 O 3 PVL exhibited remarkable mobility of 33.5-220.1 cm 2 /Vs when channel length varies from 60 to 560 μ m. This work presents a feasible way to implement high mobility and Cu electrodes in a-IGZO TFT, simultaneously.

  4. Mobility Enhancement in Amorphous In-Ga-Zn-O Thin-Film Transistor by Induced Metallic in Nanoparticles and Cu Electrodes

    PubMed Central

    Lu, Kuankuan; Li, Yuzhi; Xu, Miao; Wang, Lei; Peng, Junbiao; Lu, Xubing

    2018-01-01

    In this work, we fabricated a high-mobility amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) based on alumina oxide (Al2O3) passivation layer (PVL) and copper (Cu) source/drain electrodes (S/D). The mechanism of the high mobility for a-IGZO TFT was proposed and experimentally demonstrated. The conductivity of the channel layer was significantly improved due to the formation of metallic In nanoparticles on the back channel during Al2O3 PVL sputtering. In addition, Ar atmosphere annealing induced the Schottky contact formation between the Cu S/D and the channel layer caused by Cu diffusion. In conjunction with high conductivity channel and Schottky contact, the a-IGZO TFT based on Cu S/D and Al2O3 PVL exhibited remarkable mobility of 33.5–220.1 cm2/Vs when channel length varies from 60 to 560 μm. This work presents a feasible way to implement high mobility and Cu electrodes in a-IGZO TFT, simultaneously. PMID:29584710

  5. Facile one-step synthesis of magnesium-doped ZnO nanoparticles: optical properties and their device applications

    NASA Astrophysics Data System (ADS)

    Oh, Ji-Young; Lim, Sang-Chul; Ahn, Seong Deok; Lee, Sang Seok; Cho, Kyoung-Ik; Bon Koo, Jae; Choi, Rino; Hasan, Musarrat

    2013-07-01

    In this study, magnesium-doped (Mg-doped) zinc oxide (ZnO) nanoparticles were successfully synthesized by a sonochemical process under mild conditions. The x-ray diffraction pattern indicated that the Mg-doped ZnO nanoparticles maintain a wurtzite structure without impurities. We observed a blue-shift of the bandgap of the Mg-doped ZnO nanoparticles as the Mg-doping ratio increased. We also fabricated thin-film transistor (TFT) devices with the doped-ZnO nanoparticles. Devices using Mg-doped ZnO nanoparticles as a channel layer showed insensibility to white-light irradiation compared with undoped ZnO TFTs.

  6. Investigation of the ferroelectric switching behavior of P(VDF-TrFE)-PMMA blended films for synaptic device applications

    NASA Astrophysics Data System (ADS)

    Kim, E. J.; Kim, K. A.; Yoon, S. M.

    2016-02-01

    Synaptic plasticity can be mimicked by electronic synaptic devices. By using ferroelectric thin films as gate insulator for thin-film transistors (TFT), channel conductance can be defined as the synaptic plasticity, and gradually modulated by the variations in amounts of aligned ferroelectric dipoles. Poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)]-poly(methyl methacrylate) (PMMA) blended films are chosen and their switching kinetics are investigated by using the Kolmogorov-Avrami-Ishibashi model. The switching time for ferroelectric polarization is sensitively influenced by the amplitude of applied electric field and volumetric ratio of ferroelectric beta-phases in the P(VDF-TrFE)-PMMA films. The switching time of the P(VDF-TrFE) increases with decreasing the pulse amplitude and/or the ratio of ferroelectric beta-phases by incorporation of PMMA. The activation electric field is also found to increase as the increase in blended amount of PMMA. Synapse TFTs are fabricated using the P(VDF-TrFE)-PMMA as gate insulator and In-Ga-Zn-O active channels. The drain currents of the synapse TFTs gradually increased when the voltage pulse signals with given duration are repeatedly applied. This suggests that the synaptic weights can be modulated by the number of external pulse signals, and that the proposed synapse TFT can be applied for mimicking the operations of bio-synapses.

  7. PLASMA DEVICE

    DOEpatents

    Baker, W.R.; Brathenahl, A.; Furth, H.P.

    1962-04-10

    A device for producing a confined high temperature plasma is described. In the device the concave inner surface of an outer annular electrode is disposed concentrically about and facing the convex outer face of an inner annular electrode across which electrodes a high potential is applied to produce an electric field there between. Means is provided to create a magnetic field perpendicular to the electric field and a gas is supplied at reduced pressure in the area therebetween. Upon application of the high potential, the gas between the electrodes is ionized, heated, and under the influence of the electric and magnetic fields there is produced a rotating annular plasma disk. The ionized plasma has high dielectric constant properties. The device is useful as a fast discharge rate capacitor, in controlled thermonuclear research, and other high temperature gas applications. (AEC)

  8. Toward the Limits of Uniformity of Mixed Metallicity SWCNT TFT Arrays with Spark-Synthesized and Surface-Density-Controlled Nanotube Networks.

    PubMed

    Kaskela, Antti; Mustonen, Kimmo; Laiho, Patrik; Ohno, Yutaka; Kauppinen, Esko I

    2015-12-30

    We report the fabrication of thin film transistors (TFTs) from networks of nonbundled single-walled carbon nanotubes with controlled surface densities. Individual nanotubes were synthesized by using a spark generator-based floating catalyst CVD process. High uniformity and the control of SWCNT surface density were realized by mixing of the SWCNT aerosol in a turbulent flow mixer and monitoring the online number concentration with a condensation particle counter at the reactor outlet in real time. The networks consist of predominantly nonbundled SWCNTs with diameters of 1.0-1.3 nm, mean length of 3.97 μm, and metallic to semiconducting tube ratio of 1:2. The ON/OFF ratio and charge carrier mobility of SWCNT TFTs were simultaneously optimized through fabrication of devices with SWCNT surface densities ranging from 0.36 to 1.8 μm(-2) and channel lengths and widths from 5 to 100 μm and from 100 to 500 μm, respectively. The density optimized TFTs exhibited excellent performance figures with charge carrier mobilities up to 100 cm(2) V(-1) s(-1) and ON/OFF current ratios exceeding 1 × 10(6), combined with high uniformity and more than 99% of devices working as theoretically expected.

  9. Analytical Device

    NASA Technical Reports Server (NTRS)

    1983-01-01

    In the mid 60s under contract with NASA, Dr. Benjamin W. Grunbaum was responsible for the development of an automated electrophoresis device that would work in the weightless environment of space. The device was never used in space but was revived during the mid 70s as a technology utilization project aimed at an automated system for use on Earth. The advanced system became known as the Grunbaum System for electrophoresis. It is a versatile, economical assembly for rapid separation of specific blood proteins in very small quantities, permitting their subsequent identification and quantification.

  10. Electrochemical device

    DOEpatents

    Grimes, Patrick G.; Einstein, Harry; Bellows, Richard J.

    1988-01-12

    A tunnel protected electrochemical device features channels fluidically communicating between manifold, tunnels and cells. The channels are designed to provide the most efficient use of auxiliary power. The channels have a greater hydraulic pressure drop and electrical resistance than the manifold. This will provide a design with the optimum auxiliary energy requirements.

  11. Detection device

    DOEpatents

    Smith, Jay E.

    1984-01-01

    The present invention is directed to a detection device comprising: (1) an entrance chamber, (2) a central chamber, and (3) an exit chamber. The central chamber includes an ionizing gas, anode, and means for connecting the anode with an external power supply and pulse counter.

  12. Detection device

    DOEpatents

    Smith, J.E.

    1981-02-27

    The present invention is directed to a detection device comprising: (1) an entrance chamber; (2) a central chamber; and (3) an exit chamber. The central chamber includes an ionizing gas, anode, and means for connecting the anode with an external power supply and pulse counter.

  13. Cleaning devices

    NASA Technical Reports Server (NTRS)

    Schneider, Horst W. (Inventor)

    1981-01-01

    Cleaning devices are described which include a vacuum cleaner nozzle with a sharp rim for directing incoming air down against the floor; a vacuum cleaner wherein electrostatically charged brushes that brush dirt off a floor, are electrically grounded to remove charges that could tend to hold dirt to the brushes; a vacuum cleaner head having slots that form a pair of counter-rotating vortices, and that includes an outlet that blows a stream of air at the floor region which lies between the vortices; a cleaning device that sweeps a group of brushes against the ground along a first direction, and then sweeps them along the same ground area but in a second direction angled from the first by an amount such as 90.degree., to sweep up particles lying in crevices extending along any direction; a device that gently cleans a surface to remove bacteria for analysis, including an inclined wall along which cleaning fluid flows onto the surface, a vacuum chamber for drawing in the cleaning fluid, and a dividing wall spaced slightly from the surface to separate the fluid source from the vacuum cleaner chamber; and a device for providing pulses of pressured air including a chamber to which pressured air is supplied, a ball that circulates around the chamber to repeatedly close an outlet, and an air source that directs air circumferentially to move the ball around the chamber.

  14. Coplanar amorphous-indium-gallium-zinc-oxide thin film transistor with He plasma treated heavily doped layer

    SciTech Connect

    Jeong, Ho-young; LG Display R and D Center, 245 Lg-ro, Wollong-myeon, Paju-si, Gyeonggi-do 413-811; Lee, Bok-young

    We report thermally stable coplanar amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) with heavily doped n{sup +} a-IGZO source/drain regions. Doping is through He plasma treatment in which the resistivity of the a-IGZO decreases from 2.98 Ω cm to 2.79 × 10{sup −3} Ω cm after treatment, and then it increases to 7.92 × 10{sup −2} Ω cm after annealing at 300 °C. From the analysis of X-ray photoelectron spectroscopy, the concentration of oxygen vacancies in He plasma treated n{sup +}a-IGZO does not change much after thermal annealing at 300 °C, indicating thermally stable n{sup +} a-IGZO, even for TFTs with channel length L = 4 μm. Field-effect mobility of the coplanar a-IGZO TFTsmore » with He plasma treatment changes from 10.7 to 9.2 cm{sup 2}/V s after annealing at 300 °C, but the performance of the a-IGZO TFT with Ar or H{sub 2} plasma treatment degrades significantly after 300 °C annealing.« less

  15. A transparent electrochromic metal-insulator switching device with three-terminal transistor geometry

    NASA Astrophysics Data System (ADS)

    Katase, Takayoshi; Onozato, Takaki; Hirono, Misako; Mizuno, Taku; Ohta, Hiromichi

    2016-05-01

    Proton and hydroxyl ion play an essential role for tuning functionality of oxides because their electronic state can be controlled by modifying oxygen off-stoichiometry and/or protonation. Tungsten trioxide (WO3), a well-known electrochromic (EC) material for smart window, is a wide bandgap insulator, whereas it becomes a metallic conductor HxWO3 by protonation. Although one can utilize electrochromism together with metal-insulator (MI) switching for one device, such EC-MI switching cannot be utilized in current EC devices because of their two-terminal structure with parallel-plate configuration. Here we demonstrate a transparent EC-MI switchable device with three-terminal TFT-type structure using amorphous (a-) WO3 channel layer, which was fabricated on glass substrate at room temperature. We used water-infiltrated nano-porous glass, CAN (calcium aluminate with nano-pores), as a liquid-leakage-free solid gate insulator. At virgin state, the device was fully transparent in the visible-light region. For positive gate voltage, the active channel became dark blue, and electrical resistivity of the a-WO3 layer drastically decreased with protonation. For negative gate voltage, deprotonation occurred and the active channel returned to transparent insulator. Good cycleability of the present transparent EC-MI switching device would have potential for the development of advanced smart windows.

  16. LOADING DEVICE

    DOEpatents

    Ohlinger, L.A.

    1958-10-01

    A device is presented for loading or charging bodies of fissionable material into a reactor. This device consists of a car, mounted on tracks, into which the fissionable materials may be placed at a remote area, transported to the reactor, and inserted without danger to the operating personnel. The car has mounted on it a heavily shielded magazine for holding a number of the radioactive bodies. The magazine is of a U-shaped configuration and is inclined to the horizontal plane, with a cap covering the elevated open end, and a remotely operated plunger at the lower, closed end. After the fissionable bodies are loaded in the magazine and transported to the reactor, the plunger inserts the body at the lower end of the magazine into the reactor, then is withdrawn, thereby allowing gravity to roll the remaining bodies into position for successive loading in a similar manner.

  17. Laser device

    DOEpatents

    Scott, Jill R.; Tremblay, Paul L.

    2008-08-19

    A laser device includes a virtual source configured to aim laser energy that originates from a true source. The virtual source has a vertical rotational axis during vertical motion of the virtual source and the vertical axis passes through an exit point from which the laser energy emanates independent of virtual source position. The emanating laser energy is collinear with an orientation line. The laser device includes a virtual source manipulation mechanism that positions the virtual source. The manipulation mechanism has a center of lateral pivot approximately coincident with a lateral index and a center of vertical pivot approximately coincident with a vertical index. The vertical index and lateral index intersect at an index origin. The virtual source and manipulation mechanism auto align the orientation line through the index origin during virtual source motion.

  18. Latching device

    NASA Technical Reports Server (NTRS)

    Ulrich, G. W. (Inventor)

    1975-01-01

    A latching device is suited for use in establishing a substantially motionless connection between a stationary receiver and a movable latching mechanism. The latching mechanism includes a pivotally supported restraining hook continuously urged into a capturing relationship with the receiver, characterized by a spring-biased pawl having a plurality of aligned teeth. The teeth are seated in the surface of the throat of the hook and positionable into restraining engagement with a rigid restraining shoulder projected from the receiver.

  19. The electrical performance and gate bias stability of an amorphous InGaZnO thin-film transistor with HfO2 high-k dielectrics

    NASA Astrophysics Data System (ADS)

    Wang, Ruo Zheng; Wu, Sheng Li; Li, Xin Yu; Zhang, Jin Tao

    2017-07-01

    In this study, we set out to fabricate an amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor (TFT) with SiNx/HfO2/SiNx (SHS) sandwiched dielectrics. The J-V and C-V of this SHS film were extracted by the Au/p-Si/SHS/Ti structure. At room temperature the a-IGZO with SHS dielectrics showed the following electrical properties: a threshold voltage of 2.9 V, a subthreshold slope of 0.35 V/decade, an on/off current ratio of 3.5 × 107, and a mobility of 12.8 cm2 V-1 s-1. Finally, we tested the influence of gate bias stress on the TFT, and the result showed that the threshold voltage shifted to a positive voltage when applying a positive gate voltage to the TFT.

  20. Negative gate bias and light illumination-induced hump in amorphous InGaZnO thin film transistor.

    PubMed

    Jeon, Jae-Hong; Seo, Seung-Bum; Park, Han-Sung; Choe, Hee-Hwan; Seo, Jong-Hyun; Park, Kee-Chan; Park, Sang-Hee Ko

    2013-11-01

    While observing the transfer characteristics of a-IGZO TFTs, it was noticed that a hump occurred in the subthreshold regime after light and bias stress. This study analyzes the mechanism of the hump occurrence. It was determined that hump characteristics were related with parasitic TFTs which formed at the peripheral edges parallel with the channel direction. It seems that the negative shift of the transfer characteristics of parasitic TFTs was larger than that of the main TFT under light and bias stress. Therefore, the difference in the negative shift between the main TFT and the parasitic TFT was the origin of the hump occurrence. We investigated the instability of a-IGZO TFTs under negative gate bias with light illumination for various channel structures in order to verify the above mechanism.

  1. Electrochromic device

    DOEpatents

    Schwendemanm, Irina G [Wexford, PA; Polcyn, Adam D [Pittsburgh, PA; Finley, James J [Pittsburgh, PA; Boykin, Cheri M [Kingsport, TN; Knowles, Julianna M [Apollo, PA

    2011-03-15

    An electrochromic device includes a first substrate spaced from a second substrate. A first conductive member is formed over at least a portion of the first substrate. A first electrochromic material is formed over at least a portion of the first conductive member. The first electrochromic material includes an organic material. A second conductive member is formed over at least a portion of the second substrate. A second electrochromic material is formed over at least a portion of the second conductive member. The second electrochromic material includes an inorganic material. An ionic liquid is positioned between the first electrochromic material and the second electrochromic material.

  2. Diversionary device

    DOEpatents

    Grubelich, Mark C.

    2001-01-01

    A diversionary device has a housing having at least one opening and containing a non-explosive propellant and a quantity of fine powder packed within the housing, with the powder being located between the propellant and the opening. When the propellant is activated, it has sufficient energy to propel the powder through the opening to produce a cloud of powder outside the housing. An igniter is also provided for igniting the cloud of powder to create a diversionary flash and bang, but at a low enough pressure to avoid injuring nearby people.

  3. Device Connectivity

    PubMed Central

    Walsh, John; Roberts, Ruth; Morris, Richard

    2015-01-01

    Patients with diabetes have to take numerous factors/data into their therapeutic decisions in daily life. Connecting the devices they are using by feeding the data generated into a database/app is supposed to help patients to optimize their glycemic control. As this is not established in practice, the different roadblocks have to be discussed to open the road. That large telecommunication companies are now entering this market might be a big help in pushing this forward. Smartphones offer an ideal platform for connectivity solutions. PMID:25614015

  4. Electrospray device

    NASA Technical Reports Server (NTRS)

    Demmons, Nathaniel (Inventor); Roy, Thomas (Inventor); Spence, Douglas (Inventor); Martin, Roy (Inventor); Hruby, Vladimir (Inventor); Ehrbar, Eric (Inventor); Zwahlen, Jurg (Inventor)

    2011-01-01

    An electrospray device includes an electrospray emitter adapted to receive electrospray fluid; an extractor plate spaced from the electrospray emitter and having at least one aperture; and a power supply for applying a first voltage between the extractor plate and emitter for generating at least one Taylor cone emission through the aperture to create an electrospray plume from the electrospray fluid, the extractor plate as well as accelerator and shaping plates may include a porous, conductive medium for transporting and storing excess, accumulated electrospray fluid away from the aperture.

  5. Printed indium gallium zinc oxide transistors. Self-assembled nanodielectric effects on low-temperature combustion growth and carrier mobility.

    PubMed

    Everaerts, Ken; Zeng, Li; Hennek, Jonathan W; Camacho, Diana I; Jariwala, Deep; Bedzyk, Michael J; Hersam, Mark C; Marks, Tobin J

    2013-11-27

    Solution-processed amorphous oxide semiconductors (AOSs) are emerging as important electronic materials for displays and transparent electronics. We report here on the fabrication, microstructure, and performance characteristics of inkjet-printed, low-temperature combustion-processed, amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) grown on solution-processed hafnia self-assembled nanodielectrics (Hf-SANDs). TFT performance for devices processed below 300 °C includes >4× enhancement in electron mobility (μFE) on Hf-SAND versus SiO2 or ALD-HfO2 gate dielectrics, while other metrics such as subthreshold swing (SS), current on:off ratio (ION:IOFF), threshold voltage (Vth), and gate leakage current (Ig) are unchanged or enhanced. Thus, low voltage IGZO/SAND TFT operation (<2 V) is possible with ION:IOFF = 10(7), SS = 125 mV/dec, near-zero Vth, and large electron mobility, μFE(avg) = 20.6 ± 4.3 cm(2) V(-1) s(-1), μFE(max) = 50 cm(2) V(-1) s(-1). Furthermore, X-ray diffraction analysis indicates that the 300 °C IGZO combustion processing leaves the underlying Hf-SAND microstructure and capacitance intact. This work establishes the compatibility and advantages of all-solution, low-temperature fabrication of inkjet-printed, combustion-derived high-mobility IGZO TFTs integrated with self-assembled hybrid organic-inorganic nanodielectrics.

  6. CLOSURE DEVICE

    DOEpatents

    Linzell, S.M.; Dorcy, D.J.

    1958-08-26

    A quick opening type of stuffing box employing two banks of rotatable shoes, each of which has a caraming action that forces a neoprene sealing surface against a pipe or rod where it passes through a wall is presented. A ring having a handle or wrench attached is placed eccentric to and between the two banks of shoes. Head bolts from the shoes fit into slots in this ring, which are so arranged that when the ring is rotated a quarter turn in one direction the shoes are thrust inwardly to cramp the neopnrene about the pipe, malting a tight seal. Moving the ring in the reverse direction moves the shoes outwardly and frees the pipe which then may be readily removed from the stuffing box. This device has particular application as a closure for the end of a coolant tube of a neutronic reactor.

  7. PLASMA DEVICE

    DOEpatents

    Baker, W.R.

    1961-08-22

    A device is described for establishing and maintaining a high-energy, rotational plasma for use as a fast discharge capacitor. A disc-shaped, current- conducting plasma is formed in an axinl magnetic field and a crossed electric field, thereby creating rotational kinetic enengy in the plasma. Such energy stored in the rotation of the plasma disc is substantial and is convertible tc electrical energy by generator action in an output line electrically coupled to the plasma volume. Means are then provided for discharging the electrical energy into an external circuit coupled to the output line to produce a very large pulse having an extremely rapid rise time in the waveform thereof. (AE C)

  8. Optoelectronic device

    DOEpatents

    Bonekamp, Jeffrey E.; Boven, Michelle L.; Gaston, Ryan S.

    2014-09-09

    The invention is an optoelectronic device comprising an active portion which converts light to electricity or converts electricity to light, the active portion having a front side for the transmittal of the light and a back side opposite from the front side, at least two electrical leads to the active portion to convey electricity to or from the active portion, an enclosure surrounding the active portion and through which the at least two electrical leads pass wherein the hermetically sealed enclosure comprises at the front side of the active portion a barrier material which allows for transmittal of light, one or more getter materials disposed so as to not impede the transmission of light to or from the active portion, and a contiguous gap pathway to the getter material which pathway is disposed between the active portion and the barrier material.

  9. Electrophoresis device

    NASA Technical Reports Server (NTRS)

    Rhodes, P. H.; Snyder, R. S. (Inventor)

    1982-01-01

    A device for separating cellular particles of a sample substance into fractionated streams of different cellular species includes a casing having a distribution chamber, a separation chamber, and a collection chamber. The electrode chambers are separated from the separation chamber interior by means of passages such that flow variations and membrane variations around the slotted portion of the electrode chamber do not enduce flow perturbations into the laminar buffer curtain flowing in the separation chamber. The cellular particles of the sample are separated under the influence of the electrical field and the separation chamber into streams of different cellular species. The streams of separated cells enter a partition array in the collection chamber where they are fractionated and collected.

  10. Integrated device architectures for electrochromic devices

    DOEpatents

    Frey, Jonathan Mack; Berland, Brian Spencer

    2015-04-21

    This disclosure describes systems and methods for creating monolithically integrated electrochromic devices which may be a flexible electrochromic device. Monolithic integration of thin film electrochromic devices may involve the electrical interconnection of multiple individual electrochromic devices through the creation of specific structures such as conductive pathway or insulating isolation trenches.

  11. Laser device

    DOEpatents

    Scott, Jill R [Idaho Falls, ID; Tremblay, Paul L [Idaho Falls, ID

    2007-07-10

    A laser device includes a target position, an optical component separated a distance J from the target position, and a laser energy source separated a distance H from the optical component, distance H being greater than distance J. A laser source manipulation mechanism exhibits a mechanical resolution of positioning the laser source. The mechanical resolution is less than a spatial resolution of laser energy at the target position as directed through the optical component. A vertical and a lateral index that intersect at an origin can be defined for the optical component. The manipulation mechanism can auto align laser aim through the origin during laser source motion. The laser source manipulation mechanism can include a mechanical index. The mechanical index can include a pivot point for laser source lateral motion and a reference point for laser source vertical motion. The target position can be located within an adverse environment including at least one of a high magnetic field, a vacuum system, a high pressure system, and a hazardous zone. The laser source and an electro-mechanical part of the manipulation mechanism can be located outside the adverse environment. The manipulation mechanism can include a Peaucellier linkage.

  12. Laser device

    DOEpatents

    Scott, Jill R.; Tremblay, Paul L.

    2004-11-23

    A laser device includes a target position, an optical component separated a distance J from the target position, and a laser energy source separated a distance H from the optical component, distance H being greater than distance J. A laser source manipulation mechanism exhibits a mechanical resolution of positioning the laser source. The mechanical resolution is less than a spatial resolution of laser energy at the target position as directed through the optical component. A vertical and a lateral index that intersect at an origin can be defined for the optical component. The manipulation mechanism can auto align laser aim through the origin during laser source motion. The laser source manipulation mechanism can include a mechanical index. The mechanical index can include a pivot point for laser source lateral motion and a reference point for laser source vertical motion. The target position can be located within an adverse environment including at least one of a high magnetic field, a vacuum system, a high pressure system, and a hazardous zone. The laser source and an electro-mechanical part of the manipulation mechanism can be located outside the adverse environment. The manipulation mechanism can include a Peaucellier linkage.

  13. Effective mobility enhancement of amorphous In-Ga-Zn-O thin-film transistors by holographically generated periodic conductor

    SciTech Connect

    Jeong, Jaewook; Kim, Joonwoo; Jeong, Soon Moon

    In this study, we demonstrate a mobility enhancement structure for fully transparent amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs) by embedding a holographically generated periodic nano-conductor in the back-channel regions. The intrinsic field-effect mobility was enhanced up to 2 times compared to that of a reference sample. The enhancement originated from a decrease in the effective channel length due to the highly conductive nano-conductor region. By combining conventional and holographic lithography, the performance of the a-IGZO TFT can be effectively improved without varying the composition of the channel layer.

  14. Effective mobility enhancement of amorphous In-Ga-Zn-O thin-film transistors by holographically generated periodic conductor

    NASA Astrophysics Data System (ADS)

    Jeong, Jaewook; Kim, Joonwoo; Kim, Donghyun; Jeon, Heonsu; Jeong, Soon Moon; Hong, Yongtaek

    2016-08-01

    In this study, we demonstrate a mobility enhancement structure for fully transparent amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs) by embedding a holographically generated periodic nano-conductor in the back-channel regions. The intrinsic field-effect mobility was enhanced up to 2 times compared to that of a reference sample. The enhancement originated from a decrease in the effective channel length due to the highly conductive nano-conductor region. By combining conventional and holographic lithography, the performance of the a-IGZO TFT can be effectively improved without varying the composition of the channel layer.

  15. Toward Adequate Operation of Amorphous Oxide Thin-Film Transistors for Low-Concentration Gas Detection.

    PubMed

    Kim, Kyung Su; Ahn, Cheol Hyoun; Jung, Sung Hyeon; Cho, Sung Woon; Cho, Hyung Koun

    2018-03-28

    We suggest the use of a thin-film transistor (TFT) composed of amorphous InGaZnO (a-IGZO) as a channel and a sensing layer for low-concentration NO 2 gas detection. Although amorphous oxide layers have a restricted surface area when reacting with NO 2 gas, such TFT sensors have incomparable advantages in the aspects of electrical stability, large-scale uniformity, and the possibility of miniaturization. The a-IGZO thin films do not possess typical reactive sites and grain boundaries, so that the variation in drain current of the TFTs strictly originates from oxidation reaction between channel surface and NO 2 gas. Especially, the sensing data obtained from the variation rate of drain current makes it possible to monitor efficiently and quickly the variation of the NO 2 concentration. Interestingly, we found that enhancement-mode TFT (EM-TFT) allows discrimination of the drain current variation rate at NO 2 concentrations ≤10 ppm, whereas a depletion-mode TFT is adequate for discriminating NO 2 concentrations ≥10 ppm. This discrepancy is attributed to the ratio of charge carriers contributing to gas capture with respect to total carriers. This capacity for the excellent detection of low-concentration NO 2 gas can be realized through (i) three-terminal TFT gas sensors using amorphous oxide, (ii) measurement of the drain current variation rate for high selectivity, and (iii) an EM mode driven by tuning the electrical conductivity of channel layers.

  16. The effect of annealing ambient on the characteristics of an indium-gallium-zinc oxide thin film transistor.

    PubMed

    Park, Soyeon; Bang, Seokhwan; Lee, Seungjun; Park, Joohyun; Ko, Youngbin; Jeon, Hyeongtag

    2011-07-01

    In this study, the effects of different annealing conditions (air, O2, N2, vacuum) on the chemical and electrical characteristics of amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFT) were investigated. The contact resistance and interface properties between the IGZO film and the gate dielectric improved after an annealing treatment. However, the chemical bonds in the IGZO bulk changed under various annealing atmospheres, which, in turn, altered the characteristics of the TFTs. The TFTs annealed in vacuum and N2 ambients exhibited undesired switching properties due to the high carrier concentration (>10(17) cm(-3)) of the IGZO active layer. In contrast, the IGZO TFTs annealed in air and oxygen ambients displayed clear transfer characteristics due to an adequately adjusted carrier concentration in the operating range of the TFT. Such an optimal carrier concentration arose through the stabilization of unstable chemical bonds in the IGZO film. With regard to device performance, the TFTs annealed in O2 and air exhibited saturation mobility values of 8.29 and 7.54 cm2/Vs, on-off ratios of 7.34 x 10(8) and 3.95 x 10(8), and subthreshold swing (SS) values of 0.23 and 0.19 V/decade, respectively. Therefore, proper annealing ambients contributed to internal modifications in the IGZO structure and led to an enhancement in the oxidation state of the metal. As a result, defects such as oxygen vacancies were eliminated. Oxygen annealing is thus effective for controlling the carrier concentration of the active layer, decreasing electron traps, and enhancing TFT performance.

  17. Connector device for building integrated photovoltaic device

    DOEpatents

    Keenihan, James R.; Langmaid, Joe A.; Eurich, Gerald K.; Lesniak, Michael J.; Mazor, Michael H.; Cleerman, Robert J.; Gaston, Ryan S.

    2015-11-10

    The present invention is premised upon a connector device and method that can more easily electrically connect a plurality of PV devices or photovoltaic system components and/or locate these devices/components upon a building structure. It also may optionally provide some additional sub-components (e.g. at least one bypass diode and/or an indicator means) and may enhance the serviceability of the device.

  18. Connector device for building integrated photovoltaic device

    DOEpatents

    Keenihan, James R.; Langmaid, Joseph A.; Eurich, Gerald K.; Lesniak, Michael J.; Mazor, Michael H.; Cleereman, Robert J.; Gaston, Ryan S.

    2014-06-03

    The present invention is premised upon a connector device and method that can more easily electrically connect a plurality of PV devices or photovoltaic system components and/or locate these devices/components upon a building structure. It also may optionally provide some additional sub-components (e.g. at least one bypass diode and/or an indicator means) and may enhance the serviceability of the device.

  19. Medical Device Safety

    MedlinePlus

    A medical device is any product used to diagnose, cure, or treat a condition, or to prevent disease. They ... may need one in a hospital. To use medical devices safely Know how your device works. Keep ...

  20. CONTROL LIMITER DEVICE

    DOEpatents

    DeShong, J.A.

    1960-03-01

    A control-limiting device for monltoring a control system is described. The system comprises a conditionsensing device, a condition-varying device exerting a control over the condition, and a control means to actuate the condition-varying device. A control-limiting device integrates the total movement or other change of the condition-varying device over any interval of time during a continuum of overlapping periods of time, and if the tothl movement or change of the condition-varying device exceeds a preset value, the control- limiting device will switch the control of the operated apparatus from automatic to manual control.

  1. Electrical and structural characterization of IZO (indium oxide-zinc oxide) thin films for device applications

    NASA Astrophysics Data System (ADS)

    Yaglioglu, Burag

    Materials for oxide-based transparent electronics have been recently reported in the literature. These materials include various amorphous and crystalline compounds based on multi-component oxides and many of them offer useful combinations of transparency, controllable carrier concentrations, and reasonable n-carrier mobility. In this thesis, the properties of amorphous and crystalline In2O3-10wt%ZnO, IZO, thin films were investigated for their potential use in oxide electronics. The room temperature deposition of this material using DC magnetron sputtering results in the formation of amorphous films. Annealing amorphous IZO films at 500°C in air produces a previously unknown crystalline compound. Using electron diffraction experiments, it is reported that the crystal structure of this compound is based on the high-pressure rhombohedral phase of In2O3. Electrical properties of different phases of IZO were explored and it was concluded that amorphous films offer most promising characteristics for device applications. Therefore, thin film transistors (TFT) were fabricated based on amorphous IZO films where both the channel and metallization layers were deposited from the same target. The carrier densities in the channel and source-drain layers were adjusted by changing the oxygen content in the sputter chamber during deposition. The resulting transistors operate as depletion mode n-channel field effect devices with high saturation mobilities.

  2. Two-stage unified stretched-exponential model for time-dependence of threshold voltage shift under positive-bias-stresses in amorphous indium-gallium-zinc oxide thin-film transistors

    NASA Astrophysics Data System (ADS)

    Jeong, Chan-Yong; Kim, Hee-Joong; Hong, Sae-Young; Song, Sang-Hun; Kwon, Hyuck-In

    2017-08-01

    In this study, we show that the two-stage unified stretched-exponential model can more exactly describe the time-dependence of threshold voltage shift (ΔV TH) under long-term positive-bias-stresses compared to the traditional stretched-exponential model in amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs). ΔV TH is mainly dominated by electron trapping at short stress times, and the contribution of trap state generation becomes significant with an increase in the stress time. The two-stage unified stretched-exponential model can provide useful information not only for evaluating the long-term electrical stability and lifetime of the a-IGZO TFT but also for understanding the stress-induced degradation mechanism in a-IGZO TFTs.

  3. SciTech Connect

    Hanyu, Yuichiro, E-mail: y-hanyu@lucid.msl.titech.ac.jp; Domen, Kay; Nomura, Kenji

    We report an experimental evidence that some hydrogens passivate electron traps in an amorphous oxide semiconductor, a-In-Ga-Zn-O (a-IGZO). The a-IGZO thin-film transistors (TFTs) annealed at 300 °C exhibit good operation characteristics; while those annealed at ≥400 °C show deteriorated ones. Thermal desorption spectra (TDS) of H{sub 2}O indicate that this threshold annealing temperature corresponds to depletion of H{sub 2}O desorption from the a-IGZO layer. Hydrogen re-doping by wet oxygen annealing recovers the good TFT characteristic. The hydrogens responsible for this passivation have specific binding energies corresponding to the desorption temperatures of 300–430 °C. A plausible structural model is suggested.

  4. Fluid sampling device

    NASA Technical Reports Server (NTRS)

    Studenick, D. K. (Inventor)

    1977-01-01

    An inlet leak is described for sampling gases, more specifically, for selectively sampling multiple fluids. This fluid sampling device includes a support frame. A plurality of fluid inlet devices extend through the support frame and each of the fluid inlet devices include a longitudinal aperture. An opening device that is responsive to a control signal selectively opens the aperture to allow fluid passage. A closing device that is responsive to another control signal selectively closes the aperture for terminating further fluid flow.

  5. High mobility bottom gate InGaZnO thin film transistors with SiOx etch stopper

    NASA Astrophysics Data System (ADS)

    Kim, Minkyu; Jeong, Jong Han; Lee, Hun Jung; Ahn, Tae Kyung; Shin, Hyun Soo; Park, Jin-Seong; Jeong, Jae Kyeong; Mo, Yeon-Gon; Kim, Hye Dong

    2007-05-01

    The authors report on the fabrication of thin film transistors (TFTs), which use an amorphous indium gallium zinc oxide (a-IGZO) channel, by rf sputtering at room temperature and for which the channel length and width are patterned by photolithography and dry etching. To prevent plasma damage to the active channel, a 100-nm-thick SiOx layer deposited by plasma enhanced chemical vapor deposition was adopted as an etch stopper structure. The a-IGZO TFT (W /L=10μm/50μm) fabricated on glass exhibited a high field-effect mobility of 35.8cm2/Vs, a subthreshold gate swing value of 0.59V/decade, a thrseshold voltage of 5.9V, and an Ion/off ratio of 4.9×106, which is acceptable for use as the switching transistor of an active-matrix TFT backplane.

  6. Amorphous indium-gallium-zinc-oxide thin-film transistors using organic-inorganic hybrid films deposited by low-temperature plasma-enhanced chemical vapor deposition for all dielectric layers

    NASA Astrophysics Data System (ADS)

    Hsu, Chao-Jui; Chang, Ching-Hsiang; Chang, Kuei-Ming; Wu, Chung-Chih

    2017-01-01

    We investigated the deposition of high-performance organic-inorganic hybrid dielectric films by low-temperature (close to room temperature) inductively coupled plasma chemical vapor deposition (ICP-CVD) with hexamethyldisiloxane (HMDSO)/O2 precursor gas. The hybrid films exhibited low leakage currents and high breakdown fields, suitable for thin-film transistor (TFT) applications. They were successfully integrated into the gate insulator, the etch-stop layer, and the passivation layer for bottom-gate staggered amorphous In-Ga-Zn-O (a-IGZO) TFTs having the etch-stop configuration. With the double-active-layer configuration having a buffer a-IGZO back-channel layer grown in oxygen-rich atmosphere for better immunity against plasma damage, the etch-stop-type bottom-gate staggered a-IGZO TFTs with good TFT characteristics were successfully demonstrated. The TFTs showed good field-effect mobility (μFE), threshold voltage (V th), subthreshold swing (SS), and on/off ratio (I on/off) of 7.5 cm2 V-1 s-1, 2.38 V, 0.38 V/decade, and 2.2 × 108, respectively, manifesting their usefulness for a-IGZO TFTs.

  7. Sealed container sampling device

    NASA Technical Reports Server (NTRS)

    Hennigan, T. J.

    1969-01-01

    Sampling device, by means of a tapered needle, pierces a sealed container while maintaining the seal and either evacuates or pressurizes the container. This device has many applications in the chemical, preservative and battery-manufacturing industries.

  8. Traffic control device conspicuity.

    DOT National Transportation Integrated Search

    2013-08-01

    The conspicuity of a traffic control device (TCD) is defined as the probability that the device will be noticed. However, there is no agreed-upon measure of what constitutes being noticed. Various measures have been suggested, including eye fixations...

  9. Alerts and Notices (Devices)

    MedlinePlus

    ... Medical Devices Medical Device Safety Safety Communications Safety Communications Share Tweet Linkedin Pin it More sharing options ... Older safety communications are listed below. Older Safety Communications 2016 Safety Communications 2015 Safety Communications 2014 Safety ...

  10. Implantable Medical Devices

    MedlinePlus

    ... Also known as ICD ) - An ICD is a battery-powered device placed under the skin that keeps ... Pacemaker (Also known as Artificial Pacemaker) - A small battery-operated device that helps the heart beat in ...

  11. GAS DISCHARGE DEVICES

    DOEpatents

    Arrol, W.J.; Jefferson, S.

    1957-08-27

    The construction of gas discharge devices where the object is to provide a gas discharge device having a high dark current and stabilized striking voltage is described. The inventors have discovered that the introduction of tritium gas into a discharge device with a subsequent electrical discharge in the device will deposit tritium on the inside of the chamber. The tritium acts to emit beta rays amd is an effective and non-hazardous way of improving the abovementioned discharge tube characteristics

  12. Pulse flux measuring device

    DOEpatents

    Riggan, William C.

    1985-01-01

    A device for measuring particle flux comprises first and second photodiode detectors for receiving flux from a source and first and second outputs for producing first and second signals representing the flux incident to the detectors. The device is capable of reducing the first output signal by a portion of the second output signal, thereby enhancing the accuracy of the device. Devices in accordance with the invention may measure distinct components of flux from a single source or fluxes from several sources.

  13. Amorphous silicon photovoltaic devices

    DOEpatents

    Carlson, David E.; Lin, Guang H.; Ganguly, Gautam

    2004-08-31

    This invention is a photovoltaic device comprising an intrinsic or i-layer of amorphous silicon and where the photovoltaic device is more efficient at converting light energy to electric energy at high operating temperatures than at low operating temperatures. The photovoltaic devices of this invention are suitable for use in high temperature operating environments.

  14. Photovoltaic device and method

    DOEpatents

    Cleereman, Robert J; Lesniak, Michael J; Keenihan, James R; Langmaid, Joe A; Gaston, Ryan; Eurich, Gerald K; Boven, Michelle L

    2015-01-27

    The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

  15. Organic photosensitive devices

    DOEpatents

    Rand, Barry P; Forrest, Stephen R

    2013-11-26

    The present invention generally relates to organic photosensitive optoelectronic devices. More specifically, it is directed to organic photosensitive optoelectronic devices having a photoactive organic region containing encapsulated nanoparticles that exhibit plasmon resonances. An enhancement of the incident optical field is achieved via surface plasmon polariton resonances. This enhancement increases the absorption of incident light, leading to a more efficient device.

  16. Articulating feedstock delivery device

    DOEpatents

    Jordan, Kevin

    2013-11-05

    A fully articulable feedstock delivery device that is designed to operate at pressure and temperature extremes. The device incorporates an articulating ball assembly which allows for more accurate delivery of the feedstock to a target location. The device is suitable for a variety of applications including, but not limited to, delivery of feedstock to a high-pressure reaction chamber or process zone.

  17. Intermediate memory devices

    NASA Technical Reports Server (NTRS)

    Basalayev, G. V.; Kmet, A. B.; Rakov, M. A.; Tarasevich, V. A.

    1974-01-01

    Several methods of transfer and processing of data whose practical implementation requires operational memory devices are described. Devices incorporating multistable elements are proposed and their main parameters are given. The possibility of using the proposed devices for storing information for transmission in space radio communications channels is examined.

  18. Photovoltaic device and method

    DOEpatents

    Cleereman, Robert; Lesniak, Michael J.; Keenihan, James R.; Langmaid, Joe A.; Gaston, Ryan; Eurich, Gerald K.; Boven, Michelle L.

    2015-11-24

    The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

  19. Room-Temperature-Processed Flexible Amorphous InGaZnO Thin Film Transistor.

    PubMed

    Xiao, Xiang; Zhang, Letao; Shao, Yang; Zhou, Xiaoliang; He, Hongyu; Zhang, Shengdong

    2017-12-13

    A room-temperature flexible amorphous indium-gallium-zinc oxide thin film transistor (a-IGZO TFT) technology is developed on plastic substrates, in which both the gate dielectric and passivation layers of the TFTs are formed by an anodic oxidation (anodization) technique. While the gate dielectric Al 2 O 3 is grown with a conventional anodization on an Al:Nd gate electrode, the channel passivation layer Al 2 O 3 is formed using a localized anodization technique. The anodized Al 2 O 3 passivation layer shows a superior passivation effect to that of PECVD SiO 2 . The room-temperature-processed flexible a-IGZO TFT exhibits a field-effect mobility of 7.5 cm 2 /V·s, a subthreshold swing of 0.44 V/dec, an on-off ratio of 3.1 × 10 8 , and an acceptable gate-bias stability with threshold voltage shifts of 2.65 and -1.09 V under positive gate-bias stress and negative gate-bias stress, respectively. Bending and fatigue tests confirm that the flexible a-IGZO TFT also has a good mechanical reliability, with electrical performances remaining consistent up to a strain of 0.76% as well as after 1200 cycles of fatigue testing.

  20. CVD Polymers for Devices and Device Fabrication.

    PubMed

    Wang, Minghui; Wang, Xiaoxue; Moni, Priya; Liu, Andong; Kim, Do Han; Jo, Won Jun; Sojoudi, Hossein; Gleason, Karen K

    2017-03-01

    Chemical vapor deposition (CVD) polymerization directly synthesizes organic thin films on a substrate from vapor phase reactants. Dielectric, semiconducting, electrically conducting, and ionically conducting CVD polymers have all been readily integrated into devices. The absence of solvent in the CVD process enables the growth of high-purity layers and avoids the potential of dewetting phenomena, which lead to pinhole defects. By limiting contaminants and defects, ultrathin (<10 nm) CVD polymeric device layers have been fabricated in multiple laboratories. The CVD method is particularly suitable for synthesizing insoluble conductive polymers, layers with high densities of organic functional groups, and robust crosslinked networks. Additionally, CVD polymers are prized for the ability to conformally cover rough surfaces, like those of paper and textile substrates, as well as the complex geometries of micro- and nanostructured devices. By employing low processing temperatures, CVD polymerization avoids damaging substrates and underlying device layers. This report discusses the mechanisms of the major CVD polymerization techniques and the recent progress of their applications in devices and device fabrication, with emphasis on initiated CVD (iCVD) and oxidative CVD (oCVD) polymerization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Biomechanics of Interspinous Devices

    PubMed Central

    Parchi, Paolo D.; Evangelisti, Gisberto; Vertuccio, Antonella; Piolanti, Nicola; Andreani, Lorenzo; Cervi, Valentina; Giannetti, Christian; Calvosa, Giuseppe; Lisanti, Michele

    2014-01-01

    A number of interspinous devices (ISD) have been introduced in the lumbar spine implant market. Unfortunately, the use of these devices often is not associated with real comprehension of their biomechanical role. The aim of this paper is to review the biomechanical studies about interspinous devices available in the literature to allow the reader a better comprehension of the effects of these devices on the treated segment and on the adjacent segments of the spine. For this reason, our analysis will be limited to the interspinous devices that have biomechanical studies published in the literature. PMID:25114923

  2. Unitary lens semiconductor device

    DOEpatents

    Lear, K.L.

    1997-05-27

    A unitary lens semiconductor device and method are disclosed. The unitary lens semiconductor device is provided with at least one semiconductor layer having a composition varying in the growth direction for unitarily forming one or more lenses in the semiconductor layer. Unitary lens semiconductor devices may be formed as light-processing devices such as microlenses, and as light-active devices such as light-emitting diodes, photodetectors, resonant-cavity light-emitting diodes, vertical-cavity surface-emitting lasers, and resonant cavity photodetectors. 9 figs.

  3. Unitary lens semiconductor device

    DOEpatents

    Lear, Kevin L.

    1997-01-01

    A unitary lens semiconductor device and method. The unitary lens semiconductor device is provided with at least one semiconductor layer having a composition varying in the growth direction for unitarily forming one or more lenses in the semiconductor layer. Unitary lens semiconductor devices may be formed as light-processing devices such as microlenses, and as light-active devices such as light-emitting diodes, photodetectors, resonant-cavity light-emitting diodes, vertical-cavity surface-emitting lasers, and resonant cavity photodetectors.

  4. Active cleaning technique device

    NASA Technical Reports Server (NTRS)

    Shannon, R. L.; Gillette, R. B.

    1973-01-01

    The objective of this program was to develop a laboratory demonstration model of an active cleaning technique (ACT) device. The principle of this device is based primarily on the technique for removing contaminants from optical surfaces. This active cleaning technique involves exposing contaminated surfaces to a plasma containing atomic oxygen or combinations of other reactive gases. The ACT device laboratory demonstration model incorporates, in addition to plasma cleaning, the means to operate the device as an ion source for sputtering experiments. The overall ACT device includes a plasma generation tube, an ion accelerator, a gas supply system, a RF power supply and a high voltage dc power supply.

  5. Portable data collection device

    DOEpatents

    French, P.D.

    1996-06-11

    The present invention provides a portable data collection device that has a variety of sensors that are interchangeable with a variety of input ports in the device. The various sensors include a data identification feature that provides information to the device regarding the type of physical data produced by each sensor and therefore the type of sensor itself. The data identification feature enables the device to locate the input port where the sensor is connected and self adjust when a sensor is removed or replaced. The device is able to collect physical data, whether or not a function of a time. 7 figs.

  6. Portable data collection device

    DOEpatents

    French, Patrick D.

    1996-01-01

    The present invention provides a portable data collection device that has a variety of sensors that are interchangeable with a variety of input ports in the device. The various sensors include a data identification feature that provides information to the device regarding the type of physical data produced by each sensor and therefore the type of sensor itself. The data identification feature enables the device to locate the input port where the sensor is connected and self adjust when a sensor is removed or replaced. The device is able to collect physical data, whether or not a function of a time.

  7. Correlation of trap states with negative bias thermal illumination stress stabilities in amorphous In-Ga-Zn-O thin-film transistors studied by photoinduced transient spectroscopy

    NASA Astrophysics Data System (ADS)

    Hayashi, Kazushi; Ochi, Mototaka; Hino, Aya; Tao, Hiroaki; Goto, Hiroshi; Kugimiya, Toshihiro

    2017-03-01

    Negative bias thermal illumination stress (NBTIS) stabilities in amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) were studied by photoinduced transient spectroscopy (PITS). The degradation of TFT performance correlated with trap states in the channel region of a-IGZO TFTs with an etch stop layer (ESL). A prominent peak at approximately 100 K was observed in a-IGZO formed under a partial pressure (p/p) of 4% O2. With increasing O2 p/p, an apparent shoulder of around 230 K appeared in PITS spectra. A higher flow rate of SiH4/N2O for the ESL deposition induced trap states associated with the 230 K peak. The peak at approximately 100 K could originate from the depletion of Zn by preannealing, while the peak at approximately 230 K should be attributed to the oxygen-deficient and/or Zn-rich defects due to the formation of OH in a-IGZO. The trap states in a-IGZO TFTs gave rise to degradation in terms of NBTIS. The threshold voltage shift (ΔV th) was 2.5 V, but it increased with the O2 p/p as well as the flow rate of SiH4/N2O for ESL deposition. The time dependence of ΔV th suggested that hydrogen from the ESL and/or in the a-IGZO thin films was incorporated and modified the trap states in the channel region of the a-IGZO TFTs.

  8. Purification of 1.9-nm-diameter semiconducting single-wall carbon nanotubes by temperature-controlled gel-column chromatography and its application to thin-film transistor devices

    NASA Astrophysics Data System (ADS)

    Thendie, Boanerges; Omachi, Haruka; Hirotani, Jun; Ohno, Yutaka; Miyata, Yasumitsu; Shinohara, Hisanori

    2017-06-01

    Large-diameter semiconductor single-wall carbon nanotubes (s-SWCNTs) have superior mobility and conductivity to small-diameter s-SWCNTs. However, the purification of s-SWCNTs with diameters larger than 1.6 nm by gel filtration has been difficult owing to the low selectivity of the conventional purification method in these large-diameter regions. We report a combination of temperature-controlled gel filtration and the gradient elution technique that we developed to enrich a high-purity s-SWCNT with a diameter as large as 1.9 nm. The thin-film transistor (TFT) device using the 1.9-nm-diameter SWCNT shows an average channel mobility of 23.7 cm2 V-1 s-1, which is much higher than those of conventional SWCNT-TFTs with smaller-diameters of 1.5 and 1.4 nm.

  9. Pulse I-V characterization of a nano-crystalline oxide device with sub-gap density of states

    NASA Astrophysics Data System (ADS)

    Kim, Taeho; Hur, Ji-Hyun; Jeon, Sanghun

    2016-05-01

    Understanding the charge trapping nature of nano-crystalline oxide semiconductor thin film transistors (TFTs) is one of the most important requirements for their successful application. In our investigation, we employed a fast-pulsed I-V technique for understanding the charge trapping phenomenon and for characterizing the intrinsic device performance of an amorphous/nano-crystalline indium-hafnium-zinc-oxide semiconductor TFT with varying density of states in the bulk. Because of the negligible transient charging effect with a very short pulse, the source-to-drain current obtained with the fast-pulsed I-V measurement was higher than that measured by the direct-current characterization method. This is because the fast-pulsed I-V technique provides a charge-trap free environment, suggesting that it is a representative device characterization methodology of TFTs. In addition, a pulsed source-to-drain current versus time plot was used to quantify the dynamic trapping behavior. We found that the charge trapping phenomenon in amorphous/nano-crystalline indium-hafnium-zinc-oxide TFTs is attributable to the charging/discharging of sub-gap density of states in the bulk and is dictated by multiple trap-to-trap processes.

  10. Pulse I-V characterization of a nano-crystalline oxide device with sub-gap density of states.

    PubMed

    Kim, Taeho; Hur, Ji-Hyun; Jeon, Sanghun

    2016-05-27

    Understanding the charge trapping nature of nano-crystalline oxide semiconductor thin film transistors (TFTs) is one of the most important requirements for their successful application. In our investigation, we employed a fast-pulsed I-V technique for understanding the charge trapping phenomenon and for characterizing the intrinsic device performance of an amorphous/nano-crystalline indium-hafnium-zinc-oxide semiconductor TFT with varying density of states in the bulk. Because of the negligible transient charging effect with a very short pulse, the source-to-drain current obtained with the fast-pulsed I-V measurement was higher than that measured by the direct-current characterization method. This is because the fast-pulsed I-V technique provides a charge-trap free environment, suggesting that it is a representative device characterization methodology of TFTs. In addition, a pulsed source-to-drain current versus time plot was used to quantify the dynamic trapping behavior. We found that the charge trapping phenomenon in amorphous/nano-crystalline indium-hafnium-zinc-oxide TFTs is attributable to the charging/discharging of sub-gap density of states in the bulk and is dictated by multiple trap-to-trap processes.

  11. Smart portable rehabilitation devices.

    PubMed

    Mavroidis, Constantinos; Nikitczuk, Jason; Weinberg, Brian; Danaher, Gil; Jensen, Katherine; Pelletier, Philip; Prugnarola, Jennifer; Stuart, Ryan; Arango, Roberto; Leahey, Matt; Pavone, Robert; Provo, Andrew; Yasevac, Dan

    2005-07-12

    The majority of current portable orthotic devices and rehabilitative braces provide stability, apply precise pressure, or help maintain alignment of the joints with out the capability for real time monitoring of the patient's motions and forces and without the ability for real time adjustments of the applied forces and motions. Improved technology has allowed for advancements where these devices can be designed to apply a form of tension to resist motion of the joint. These devices induce quicker recovery and are more effective at restoring proper biomechanics and improving muscle function. However, their shortcoming is in their inability to be adjusted in real-time, which is the most ideal form of a device for rehabilitation. This introduces a second class of devices beyond passive orthotics. It is comprised of "active" or powered devices, and although more complicated in design, they are definitely the most versatile. An active or powered orthotic, usually employs some type of actuator(s). In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device. Laboratory tests of the devices demonstrated that they were able to meet their design

  12. Smart portable rehabilitation devices

    PubMed Central

    Mavroidis, Constantinos; Nikitczuk, Jason; Weinberg, Brian; Danaher, Gil; Jensen, Katherine; Pelletier, Philip; Prugnarola, Jennifer; Stuart, Ryan; Arango, Roberto; Leahey, Matt; Pavone, Robert; Provo, Andrew; Yasevac, Dan

    2005-01-01

    Background The majority of current portable orthotic devices and rehabilitative braces provide stability, apply precise pressure, or help maintain alignment of the joints with out the capability for real time monitoring of the patient's motions and forces and without the ability for real time adjustments of the applied forces and motions. Improved technology has allowed for advancements where these devices can be designed to apply a form of tension to resist motion of the joint. These devices induce quicker recovery and are more effective at restoring proper biomechanics and improving muscle function. However, their shortcoming is in their inability to be adjusted in real-time, which is the most ideal form of a device for rehabilitation. This introduces a second class of devices beyond passive orthotics. It is comprised of "active" or powered devices, and although more complicated in design, they are definitely the most versatile. An active or powered orthotic, usually employs some type of actuator(s). Methods In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device. Results Laboratory tests of the devices demonstrated that they were able to

  13. Prosthetic Device Infections.

    PubMed

    Martinez, Raquel M; Bowen, Thomas R; Foltzer, Michael A

    2016-08-01

    The immunocompromised host is a particularly vulnerable population in whom routine and unusual infections can easily and frequently occur. Prosthetic devices are commonly used in these patients and the infections associated with those devices present a number of challenges for both the microbiologist and the clinician. Biofilms play a major role in device-related infections, which may contribute to failed attempts to recover organisms from routine culture methods. Moreover, device-related microorganisms can be difficult to eradicate by antibiotic therapy alone. Changes in clinical practice and advances in laboratory diagnostics have provided significant improvements in the detection and accurate diagnosis of device-related infections. Disruption of the bacterial biofilm plays an essential role in recovering the causative agent in culture. Various culture and nucleic acid amplification techniques are more accurate to guide directed treatment regimens. This chapter reviews the performance characteristics of currently available diagnostic assays and summarizes published guidelines, where available, for addressing suspected infected prosthetic devices.

  14. Barrier breaching device

    DOEpatents

    Honodel, Charles A.

    1985-01-01

    A barrier breaching device that is designed primarily for opening holes in interior walls of buildings uses detonating fuse for explosive force. The fuse acts as the ribs or spokes of an umbrella-like device that may be opened up to form a cone. The cone is placed against the wall so that detonating fuse that rings the base of the device and which is ignited by the spoke-like fuses serves to cut a circular hole in the wall.

  15. Barrier breaching device

    DOEpatents

    Honodel, C.A.

    1983-06-01

    A barrier breaching device that is designed primarily for opening holes in interior walls of buildings uses detonating fuse for explosive force. The fuse acts as the ribs or spokes of an umbrella-like device that may be opened up to form a cone. The cone is placed against the wall so that detonating fuse that rings the base of the device and which is ignited by the spoke-like fuses serves to cut a circular hole in the wall.

  16. Sensor sentinel computing device

    DOEpatents

    Damico, Joseph P.

    2016-08-02

    Technologies pertaining to authenticating data output by sensors in an industrial environment are described herein. A sensor sentinel computing device receives time-series data from a sensor by way of a wireline connection. The sensor sentinel computing device generates a validation signal that is a function of the time-series signal. The sensor sentinel computing device then transmits the validation signal to a programmable logic controller in the industrial environment.

  17. Ion trap device

    DOEpatents

    Ibrahim, Yehia M.; Smith, Richard D.

    2016-01-26

    An ion trap device is disclosed. The device includes a series of electrodes that define an ion flow path. A radio frequency (RF) field is applied to the series of electrodes such that each electrode is phase shifted approximately 180 degrees from an adjacent electrode. A DC voltage is superimposed with the RF field to create a DC gradient to drive ions in the direction of the gradient. A second RF field or DC voltage is applied to selectively trap and release the ions from the device. Further, the device may be gridless and utilized at high pressure.

  18. High efficiency photovoltaic device

    DOEpatents

    Guha, Subhendu; Yang, Chi C.; Xu, Xi Xiang

    1999-11-02

    An N-I-P type photovoltaic device includes a multi-layered body of N-doped semiconductor material which has an amorphous, N doped layer in contact with the amorphous body of intrinsic semiconductor material, and a microcrystalline, N doped layer overlying the amorphous, N doped material. A tandem device comprising stacked N-I-P cells may further include a second amorphous, N doped layer interposed between the microcrystalline, N doped layer and a microcrystalline P doped layer. Photovoltaic devices thus configured manifest improved performance, particularly when configured as tandem devices.

  19. Interconnected semiconductor devices

    DOEpatents

    Grimmer, Derrick P.; Paulson, Kenneth R.; Gilbert, James R.

    1990-10-23

    Semiconductor layer and conductive layer formed on a flexible substrate, divided into individual devices and interconnected with one another in series by interconnection layers and penetrating terminals.

  20. Preloaded latching device

    NASA Technical Reports Server (NTRS)

    Wesselski, Clarence J. (Inventor); Nagy, Kornel (Inventor)

    1992-01-01

    A latching device is disclosed which is lever operated sequentially to actuate a set of collet fingers to provide a radial expansion and to actuate a force mechanism to provide a compressive gripping force for attaching first and second devices to one another. The latching device includes a body member having elongated collet fingers which, in a deactuated condition, is insertable through bores on the first and second devices so that gripping terminal portions on the collet fingers are proximate to the end of the bore of the first device while a spring assembly on the body member is located proximate to the outer surface of a second device. A lever is rotatable through 90 deg to move a latching rod to sequentially actuate and expand collet fingers and to actuate the spring assembly by compressing it. During the first 30 deg of movement of the lever, the collet fingers are actuated by the latching rod to provide a radial expansion and during the last 60 deg of movement of the lever, the spring assembly acts as a force mechanism and is actuated to develop a compressive latching force on the devices. The latching rod and lever are connected by a camming mechanism. The amount of spring force in the spring assembly can be adjusted; the body member can be permanently attached by a telescoping assembly to one of the devices; and the structure can be used as a pulling device for removing annular bearings or the like from blind bores.

  1. Toward active-matrix lab-on-a-chip: programmable electrofluidic control enabled by arrayed oxide thin film transistors.

    PubMed

    Noh, Joo Hyon; Noh, Jiyong; Kreit, Eric; Heikenfeld, Jason; Rack, Philip D

    2012-01-21

    Agile micro- and nano-fluidic control is critical to numerous life science and chemical science synthesis as well as kinetic and thermodynamic studies. To this end, we have demonstrated the use of thin film transistor arrays as an active matrix addressing method to control an electrofluidic array. Because the active matrix method minimizes the number of control lines necessary (m + n lines for the m×n element array), the active matrix addressing method integrated with an electrofluidic platform can be a significant breakthrough for complex electrofluidic arrays (increased size or resolution) with enhanced function, agility and programmability. An amorphous indium gallium zinc oxide (a-IGZO) semiconductor active layer is used because of its high mobility of 1-15 cm(2) V(-1) s(-1), low-temperature processing and transparency for potential spectroscopy and imaging. Several electrofluidic functionalities are demonstrated using a simple 2 × 5 electrode array connected to a 2 × 5 IGZO thin film transistor array with the semiconductor channel width of 50 μm and mobility of 6.3 cm(2) V(-1) s(-1). Additionally, using the TFT device characteristics, active matrix addressing schemes are discussed as the geometry of the electrode array can be tailored to act as a storage capacitor element. Finally, requisite material and device parameters are discussed in context with a VGA scale active matrix addressed electrofluidic platform.

  2. Self-actuated device

    DOEpatents

    Hecht, Samuel L.

    1984-01-01

    A self-actuated device, of particular use as a valve or an orifice for nuclear reactor fuel and blanket assemblies, in which a gas produced by a neutron induced nuclear reaction gradually accumulates as a function of neutron fluence. The gas pressure increase occasioned by such accumulation of gas is used to actuate the device.

  3. Advanced resistive exercise device

    NASA Technical Reports Server (NTRS)

    Raboin, Jasen L. (Inventor); Niebuhr, Jason (Inventor); Cruz, Santana F. (Inventor); Lamoreaux, Christopher D. (Inventor)

    2008-01-01

    The present invention relates to an exercise device, which includes a vacuum cylinder and a flywheel. The flywheel provides an inertial component to the load, which is particularly well suited for use in space as it simulates exercising under normal gravity conditions. Also, the present invention relates to an exercise device, which has a vacuum cylinder and a load adjusting armbase assembly.

  4. Capillary interconnect device

    DOEpatents

    Renzi, Ronald F

    2013-11-19

    An interconnecting device for connecting a plurality of first fluid-bearing conduits to a corresponding plurality of second fluid-bearing conduits thereby providing fluid communication between the first fluid-bearing conduits and the second fluid-bearing conduits. The device includes a manifold and one or two ferrule plates that are held by compressive axial forces.

  5. Microwave device investigations

    NASA Technical Reports Server (NTRS)

    Choudhury, K. K. D.; Haddad, G. I.; Kwok, S. P.; Masnari, N. A.; Trew, R. J.

    1972-01-01

    Materials, devices and novel schemes for generation, amplification and detection of microwave and millimeter wave energy are studied. Considered are: (1) Schottky-barrier microwave devices; (2) intermodulation products in IMPATT diode amplifiers; and (3) harmonic generation using Read diode varactors.

  6. Helical tape forming device

    NASA Technical Reports Server (NTRS)

    Bush, J. E.; Cole, P. T.

    1969-01-01

    Using a device that is not limited to a minimum thickness or width-to-thickness ratio, a very thin metal tape or ribbon is formed into a continuous flat wound helical coil. The device imparts the desired circular shape by squeeze rolling it with an unequal force across its width.

  7. Optoelectronic Devices and Materials

    NASA Astrophysics Data System (ADS)

    Sweeney, Stephen; Adams, Alfred

    Unlike the majority of electronic devices, which are silicon based, optoelectronic devices are predominantly made using III-V semiconductor compounds such as GaAs, InP, GaN and GaSb and their alloys due to their direct band gap. Understanding the properties of these materials has been of vital importance in the development of optoelectronic devices. Since the first demonstration of a semiconductor laser in the early 1960s, optoelectronic devices have been produced in their millions, pervading our everyday lives in communications, computing, entertainment, lighting and medicine. It is perhaps their use in optical-fibre communications that has had the greatest impact on humankind, enabling high-quality and inexpensive voice and data transmission across the globe. Optical communications spawned a number of developments in optoelectronics, leading to devices such as vertical-cavity surface-emitting lasers, semiconductor optical amplifiers, optical modulators and avalanche photodiodes. In this chapter we discuss the underlying theory of operation of the most important optoelectronic devices. The influence of carrier-photon interactions is discussed in the context of producing efficient emitters and detectors. Finally we discuss how the semiconductor band structure can be manipulated to enhance device properties using quantum confinement and strain effects, and how the addition of dilute amounts of elements such as nitrogen is having a profound effect on the next generation of optoelectronic devices.

  8. Inverted organic photosensitive devices

    DOEpatents

    Forrest, Stephen R.; Bailey-Salzman, Rhonda F.

    2016-12-06

    The present disclosure relates to organic photosensitive optoelectronic devices grown in an inverted manner. An inverted organic photosensitive optoelectronic device of the present disclosure comprises a reflective electrode, an organic donor-acceptor heterojunction over the reflective electrode, and a transparent electrode on top of the donor-acceptor heterojunction.

  9. STORM INLET FILTRATION DEVICE

    EPA Science Inventory

    Five field tests were conducted to evaluate the effectiveness of the Storm and Groundwater Enhancement Systems (SAGES) device for removing contaminants from stormwater. The SAGES device is a three-stage filtering system that could be used as a best management practices (BMP) retr...

  10. Microfabricated particle focusing device

    DOEpatents

    Ravula, Surendra K.; Arrington, Christian L.; Sigman, Jennifer K.; Branch, Darren W.; Brener, Igal; Clem, Paul G.; James, Conrad D.; Hill, Martyn; Boltryk, Rosemary June

    2013-04-23

    A microfabricated particle focusing device comprises an acoustic portion to preconcentrate particles over large spatial dimensions into particle streams and a dielectrophoretic portion for finer particle focusing into single-file columns. The device can be used for high throughput assays for which it is necessary to isolate and investigate small bundles of particles and single particles.

  11. Microwave device investigations

    NASA Technical Reports Server (NTRS)

    Haddad, G. I.; Lomax, R. J.; Masnari, N. A.; Shabde, S. E.

    1971-01-01

    Several tasks were active during this report period: (1) noise modulation in avalanche-diode devices; (2) schottky-barrier microwave devices; (3) intermodulation products in IMPATT diode amplifiers; (4) harmonic generation using Read-diode varactors; and (5) fabrication of GaAs Schottky-barrier IMPATT diodes.

  12. Device for removing blackheads

    DOEpatents

    Berkovich, Tamara

    1995-03-07

    A device for removing blackheads from pores in the skin having a elongated handle with a spoon shaped portion mounted on one end thereof, the spoon having multiple small holes piercing therethrough. Also covered is method for using the device to remove blackheads.

  13. Medical Device Safety

    MedlinePlus

    ... Cooling and Heating Systems and HX2™ Temperature Management Systems Due to Revised Cleaning Instructions 05/07/18 More Medical Device Recalls Recent Medical Device Safety Communications FDA analyses and recommendations for patients and health care providers about ongoing ...

  14. Mechanical Device Traces Parabolas

    NASA Technical Reports Server (NTRS)

    Soper, Terry A.

    1989-01-01

    Mechanical device simplifies generation of parabolas of various focal lengths. Based on fundamental geometrical construction of parabola. Constancy of critical total distance enforced by maintaining cable in tension. Applications of device include design of paraboloidal antennas, approximating catenaries on drawings of powerlines or long-wire antennas, and general tracing of parabolas on drawings.

  15. Devices for hearing loss

    MedlinePlus

    ... NIDCD). Assistive devices for people with hearing, voice, speech, or language disorders. Nidcd.nih.gov Web site. www.nidcd.nih.gov/health/assistive-devices-people-hearing-voice-speech-or-language-disorders . Updated March 6, 2017. Accessed July 5, 2017. ...

  16. Fluidic nanotubes and devices

    DOEpatents

    Yang, Peidong [Berkeley, CA; He, Rongrui [El Cerrito, CA; Goldberger, Joshua [Berkeley, CA; Fan, Rong [El Cerrito, CA; Wu, Yiying [Albany, CA; Li, Deyu [Albany, CA; Majumdar, Arun [Orinda, CA

    2008-04-08

    Fluidic nanotube devices are described in which a hydrophilic, non-carbon nanotube, has its ends fluidly coupled to reservoirs. Source and drain contacts are connected to opposing ends of the nanotube, or within each reservoir near the opening of the nanotube. The passage of molecular species can be sensed by measuring current flow (source-drain, ionic, or combination). The tube interior can be functionalized by joining binding molecules so that different molecular species can be sensed by detecting current changes. The nanotube may be a semiconductor, wherein a tubular transistor is formed. A gate electrode can be attached between source and drain to control current flow and ionic flow. By way of example an electrophoretic array embodiment is described, integrating MEMs switches. A variety of applications are described, such as: nanopores, nanocapillary devices, nanoelectrophoretic, DNA sequence detectors, immunosensors, thermoelectric devices, photonic devices, nanoscale fluidic bioseparators, imaging devices, and so forth.

  17. Fluidic nanotubes and devices

    DOEpatents

    Yang, Peidong; He, Rongrui; Goldberger, Joshua; Fan, Rong; Wu, Yiying; Li, Deyu; Majumdar, Arun

    2010-01-10

    Fluidic nanotube devices are described in which a hydrophilic, non-carbon nanotube, has its ends fluidly coupled to reservoirs. Source and drain contacts are connected to opposing ends of the nanotube, or within each reservoir near the opening of the nanotube. The passage of molecular species can be sensed by measuring current flow (source-drain, ionic, or combination). The tube interior can be functionalized by joining binding molecules so that different molecular species can be sensed by detecting current changes. The nanotube may be a semiconductor, wherein a tubular transistor is formed. A gate electrode can be attached between source and drain to control current flow and ionic flow. By way of example an electrophoretic array embodiment is described, integrating MEMs switches. A variety of applications are described, such as: nanopores, nanocapillary devices, nanoelectrophoretic, DNA sequence detectors, immunosensors, thermoelectric devices, photonic devices, nanoscale fluidic bioseparators, imaging devices, and so forth.

  18. Heat tube device

    NASA Technical Reports Server (NTRS)

    Khattar, Mukesh K. (Inventor)

    1990-01-01

    The present invention discloses a heat tube device through which a working fluid can be circulated to transfer heat to air in a conventional air conditioning system. The heat tube device is disposable about a conventional cooling coil of the air conditioning system and includes a plurality of substantially U-shaped tubes connected to a support structure. The support structure includes members for allowing the heat tube device to be readily positioned about the cooling coil. An actuatable adjustment device is connected to the U-shaped tubes for allowing, upon actuation thereof, for the heat tubes to be simultaneously rotated relative to the cooling coil for allowing the heat transfer from the heat tube device to air in the air conditioning system to be selectively varied.

  19. Device for cutting protrusions

    SciTech Connect

    Bzorgi, Fariborz M

    An apparatus for clipping a protrusion of material is provided. The protrusion may, for example, be a bolt head, a nut, a rivet, a weld bead, or a temporary assembly alignment tab protruding from a substrate surface of assembled components. The apparatus typically includes a cleaver having a cleaving edge and a cutting blade having a cutting edge. Generally, a mounting structure configured to confine the cleaver and the cutting blade and permit a range of relative movement between the cleaving edge and the cutting edge is provided. Also typically included is a power device coupled to the cutting blade.more » The power device is configured to move the cutting edge toward the cleaving edge. In some embodiments the power device is activated by a momentary switch. A retraction device is also generally provided, where the retraction device is configured to move the cutting edge away from the cleaving edge.« less

  20. Theoretical investigation of the noise performance of active pixel imaging arrays based on polycrystalline silicon thin film transistors.

    PubMed

    Koniczek, Martin; Antonuk, Larry E; El-Mohri, Youcef; Liang, Albert K; Zhao, Qihua

    2017-07-01

    sampling mode, of the designs. The total electronic additive noise included noise contributions from each circuit component. The total noise results were found to exhibit a strong dependence on circuit design and operating conditions, with TFT flicker noise generally found to be the dominant noise contributor. For the single-stage designs, significantly increasing the size of the source-follower TFT substantially reduced flicker noise - with the lowest total noise found to be ~574 e [rms]. For the two-stage designs, in addition to tuning TFT sizes and introducing a low-pass filter, replacing a p-type TFT with a resistor (under the assumption in the study that resistors make no flicker noise contribution) resulted in significant noise reduction - with the lowest total noise found to be ~336 e [rms]. A methodology based on circuit simulations which facilitates comprehensive explorations of signal and noise characteristics has been developed and applied to the case of poly-Si AP arrays. The encouraging results suggest that the electronic additive noise of such devices can be substantially reduced through judicious circuit design, signal amplification, and multiple sampling. This methodology could be extended to explore the noise performance of arrays employing other pixel circuitry such as that for photon counting as well as other semiconductor materials such as a-Si:H and a-IGZO. © 2017 American Association of Physicists in Medicine.

  1. Optically detonated explosive device

    NASA Technical Reports Server (NTRS)

    Yang, L. C.; Menichelli, V. J. (Inventor)

    1974-01-01

    A technique and apparatus for optically detonating insensitive high explosives, is disclosed. An explosive device is formed by containing high explosive material in a house having a transparent window. A thin metallic film is provided on the interior surface of the window and maintained in contact with the high explosive. A laser pulse provided by a Q-switched laser is focussed on the window to vaporize the metallic film and thereby create a shock wave which detonates the high explosive. Explosive devices may be concurrently or sequentially detonated by employing a fiber optic bundle to transmit the laser pulse to each of the several individual explosive devices.

  2. Corneal seal device

    NASA Technical Reports Server (NTRS)

    Baehr, E. F. (Inventor)

    1977-01-01

    A corneal seal device is provided which, when placed in an incision in the eye, permits the insertion of a surgical tool or instrument through the device into the eye. The device includes a seal chamber which opens into a tube which is adapted to be sutured to the eye and serves as an entry passage for a tool. A sealable aperture in the chamber permits passage of the tool through the chamber into the tube and hence into the eye. The chamber includes inlet ports adapted to be connected to a regulated source of irrigation fluid which provides a safe intraocular pressure.

  3. Evolution of atherectomy devices.

    PubMed

    Al Khoury, G; Chaer, R

    2011-08-01

    Percutaneous atherectomy provides an alternative approach to the endovascular treatment of peripheral atherosclerotic occlusive disease beyond angioplasty and stenting, and has the theoretical advantage of lesion debulking and minimizing barotrauma to the vessel wall. Atherectomy has evolved greatly during the last decade, with currently four FDA approved devices for the treatment of peripheral arterial disease. Several reports have focused on the initial technical success rates, and demonstrated the safety and short as well as mid-term efficacy of atherectomy devices. This article will review the evolution of current atherectomy devices and the associated literature.

  4. Introduction to Semiconductor Devices

    NASA Astrophysics Data System (ADS)

    Brennan, Kevin F.

    2005-03-01

    This volume offers a solid foundation for understanding the most important devices used in the hottest areas of electronic engineering today, from semiconductor fundamentals to state-of-the-art semiconductor devices in the telecommunications and computing industries. Kevin Brennan describes future approaches to computing hardware and RF power amplifiers, and explains how emerging trends and system demands of computing and telecommunications systems influence the choice, design and operation of semiconductor devices. In addition, he covers MODFETs and MOSFETs, short channel effects, and the challenges faced by continuing miniaturization. His book is both an excellent senior/graduate text and a valuable reference for practicing engineers and researchers.

  5. Rain sampling device

    DOEpatents

    Nelson, D.A.; Tomich, S.D.; Glover, D.W.; Allen, E.V.; Hales, J.M.; Dana, M.T.

    1991-05-14

    The present invention constitutes a rain sampling device adapted for independent operation at locations remote from the user which allows rainfall to be sampled in accordance with any schedule desired by the user. The rain sampling device includes a mechanism for directing wet precipitation into a chamber, a chamber for temporarily holding the precipitation during the process of collection, a valve mechanism for controllably releasing samples of the precipitation from the chamber, a means for distributing the samples released from the holding chamber into vessels adapted for permanently retaining these samples, and an electrical mechanism for regulating the operation of the device. 11 figures.

  6. SLUG HANDLING DEVICES

    DOEpatents

    Gentry, J.R.

    1958-09-16

    A device is described for handling fuel elements of a neutronic reactor. The device consists of two concentric telescoped contalners that may fit about the fuel element. A number of ratchet members, equally spaced about the entrance to the containers, are pivoted on the inner container and spring biased to the outer container so thnt they are forced to hear against and hold the fuel element, the weight of which tends to force the ratchets tighter against the fuel element. The ratchets are released from their hold by raising the inner container relative to the outer memeber. This device reduces the radiation hazard to the personnel handling the fuel elements.

  7. Contamination sampling device

    NASA Technical Reports Server (NTRS)

    Delgado, Felix A. (Inventor); Stern, Susan M. (Inventor)

    1998-01-01

    A contamination sample collection device has a wooden dowel with a cotton swab at one end, the cotton being covered by a nylon cloth and the wooden dowel being encapsulated by plastic tubing which is heat shrunk onto the dowel and onto a portion of the cotton swab to secure the cotton in place. Another plastic tube is heat shrunk onto the plastic that encapsulates the dowel and a portion of the nylon cloth to secure the nylon cloth in place. The device may thereafter be covered with aluminum foil protector. The device may be used for obtaining samples of contamination in clean room environments.

  8. Rain sampling device

    DOEpatents

    Nelson, Danny A.; Tomich, Stanley D.; Glover, Donald W.; Allen, Errol V.; Hales, Jeremy M.; Dana, Marshall T.

    1991-01-01

    The present invention constitutes a rain sampling device adapted for independent operation at locations remote from the user which allows rainfall to be sampled in accordance with any schedule desired by the user. The rain sampling device includes a mechanism for directing wet precipitation into a chamber, a chamber for temporarily holding the precipitation during the process of collection, a valve mechanism for controllably releasing samples of said precipitation from said chamber, a means for distributing the samples released from the holding chamber into vessels adapted for permanently retaining these samples, and an electrical mechanism for regulating the operation of the device.

  9. INTERNAL CUTTING DEVICE

    DOEpatents

    Russell, W.H. Jr.

    1959-06-30

    A device is described for removing material from the interior of a hollow workpiece so as to form a true spherical internal surface in a workpiece, or to cut radial slots of an adjustable constant depth in an already established spherical internal surface. This is accomplished by a spring loaded cutting tool adapted to move axially wherein the entire force urging the tool against the workpiece is derived from the spring. Further features of importance involve the provision of a seal between the workpiece and the cutting device and a suction device for carrying away particles of removed material.

  10. Authenticated sensor interface device

    SciTech Connect

    Coleman, Jody Rustyn; Poland, Richard W.

    A system and method for the secure storage and transmission of data is provided. A data aggregate device can be configured to receive secure data from a data source, such as a sensor, and encrypt the secure data using a suitable encryption technique, such as a shared private key technique, a public key encryption technique, a Diffie-Hellman key exchange technique, or other suitable encryption technique. The encrypted secure data can be provided from the data aggregate device to different remote devices over a plurality of segregated or isolated data paths. Each of the isolated data paths can include an optoisolatormore » that is configured to provide one-way transmission of the encrypted secure data from the data aggregate device over the isolated data path. External data can be received through a secure data filter which, by validating the external data, allows for key exchange and other various adjustments from an external source.« less

  11. Advanced underwater lift device

    NASA Technical Reports Server (NTRS)

    Flanagan, David T.; Hopkins, Robert C.

    1993-01-01

    Flexible underwater lift devices ('lift bags') are used in underwater operations to provide buoyancy to submerged objects. Commercially available designs are heavy, bulky, and awkward to handle, and thus are limited in size and useful lifting capacity. An underwater lift device having less than 20 percent of the bulk and less than 10 percent of the weight of commercially available models was developed. The design features a dual membrane envelope, a nearly homogeneous envelope membrane stress distribution, and a minimum surface-to-volume ratio. A proof-of-concept model of 50 kg capacity was built and tested. Originally designed to provide buoyancy to mock-ups submerged in NASA's weightlessness simulators, the device may have application to water-landed spacecraft which must deploy flotation upon impact, and where launch weight and volume penalties are significant. The device may also be useful for the automated recovery of ocean floor probes or in marine salvage applications.

  12. Adhesion testing device

    NASA Technical Reports Server (NTRS)

    LaPeyronnie, Glenn M. (Inventor); Huff, Charles M. (Inventor)

    2010-01-01

    The present invention provides a testing apparatus and method for testing the adhesion of a coating to a surface. The invention also includes an improved testing button or dolly for use with the testing apparatus and a self aligning button hook or dolly interface on the testing apparatus. According to preferred forms, the apparatus and method of the present invention are simple, portable, battery operated rugged, and inexpensive to manufacture and use, are readily adaptable to a wide variety of uses, and provide effective and accurate testing results. The device includes a linear actuator driven by an electric motor coupled to the actuator through a gearbox and a rotatable shaft. The electronics for the device are contained in the head section of the device. At the contact end of the device, is positioned a self aligning button hook, attached below the load cell located on the actuator shaft.

  13. Microreactor Array Device

    NASA Astrophysics Data System (ADS)

    Wiktor, Peter; Brunner, Al; Kahn, Peter; Qiu, Ji; Magee, Mitch; Bian, Xiaofang; Karthikeyan, Kailash; Labaer, Joshua

    2015-03-01

    We report a device to fill an array of small chemical reaction chambers (microreactors) with reagent and then seal them using pressurized viscous liquid acting through a flexible membrane. The device enables multiple, independent chemical reactions involving free floating intermediate molecules without interference from neighboring reactions or external environments. The device is validated by protein expressed in situ directly from DNA in a microarray of ~10,000 spots with no diffusion during three hours incubation. Using the device to probe for an autoantibody cancer biomarker in blood serum sample gave five times higher signal to background ratio compared to standard protein microarray expressed on a flat microscope slide. Physical design principles to effectively fill the array of microreactors with reagent and experimental results of alternate methods for sealing the microreactors are presented.

  14. Microreactor Array Device

    PubMed Central

    Wiktor, Peter; Brunner, Al; Kahn, Peter; Qiu, Ji; Magee, Mitch; Bian, Xiaofang; Karthikeyan, Kailash; LaBaer, Joshua

    2015-01-01

    We report a device to fill an array of small chemical reaction chambers (microreactors) with reagent and then seal them using pressurized viscous liquid acting through a flexible membrane. The device enables multiple, independent chemical reactions involving free floating intermediate molecules without interference from neighboring reactions or external environments. The device is validated by protein expressed in situ directly from DNA in a microarray of ~10,000 spots with no diffusion during three hours incubation. Using the device to probe for an autoantibody cancer biomarker in blood serum sample gave five times higher signal to background ratio compared to standard protein microarray expressed on a flat microscope slide. Physical design principles to effectively fill the array of microreactors with reagent and experimental results of alternate methods for sealing the microreactors are presented. PMID:25736721

  15. Ferroelectric Light Control Device

    NASA Technical Reports Server (NTRS)

    Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Kim, Jae-Woo (Inventor); Elliott, Jr., James R. (Inventor)

    2008-01-01

    A light control device is formed by ferroelectric material and N electrodes positioned adjacent thereto to define an N-sided regular polygonal region or circular region there between where N is a multiple of four.

  16. Slit injection device

    DOEpatents

    Alger, Terry W.; Schlitt, Leland G.; Bradley, Laird P.

    1976-06-15

    A laser cavity electron beam injection device provided with a single elongated slit window for passing a suitably shaped electron beam and means for varying the current density of the injected electron beam.

  17. Marine Sanitation Devices (MSDs)

    EPA Pesticide Factsheets

    Marine sanitation devices treat or retain sewage from vessels, and have performance standards set by the EPA. This page provides information on MSDs, including who must use an MSD, states' roles, types of MSDs and standards.

  18. High temperature measuring device

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    A temperature measuring device for very high design temperatures (to 2,000.degree. C.). The device comprises a homogenous base structure preferably in the form of a sphere or cylinder. The base structure contains a large number of individual walled cells. The base structure has a decreasing coefficient of elasticity within the temperature range being monitored. A predetermined quantity of inert gas is confined within each cell. The cells are dimensionally stable at the normal working temperature of the device. Increases in gaseous pressure within the cells will permanently deform the cell walls at temperatures within the high temperature range to be measured. Such deformation can be correlated to temperature by calibrating similarly constructed devices under known time and temperature conditions.

  19. Thermoelectric materials and devices

    NASA Technical Reports Server (NTRS)

    Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor); Talcott, Noel A. (Inventor)

    2011-01-01

    New thermoelectric materials comprise highly [111]-oriented twinned group IV alloys on the basal plane of trigonal substrates, which exhibit a high thermoelectric figure of merit and good material performance, and devices made with these materials.

  20. Optical devices: A compilation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Technological developments in the field of optics devices which have potential utility outside the aerospace community are described. Optical instrumentation, light generation and transmission, and laser techniques are among the topics covered. Patent information is given.

  1. Geometry and Cloaking Devices

    NASA Astrophysics Data System (ADS)

    Ochiai, T.; Nacher, J. C.

    2011-09-01

    Recently, the application of geometry and conformal mappings to artificial materials (metamaterials) has attracted the attention in various research communities. These materials, characterized by a unique man-made structure, have unusual optical properties, which materials found in nature do not exhibit. By applying the geometry and conformal mappings theory to metamaterial science, it may be possible to realize so-called "Harry Potter cloaking device". Although such a device is still in the science fiction realm, several works have shown that by using such metamaterials it may be possible to control the direction of the electromagnetic field at will. We could then make an object hidden inside of a cloaking device. Here, we will explain how to design invisibility device using differential geometry and conformal mappings.

  2. Intrauterine device (image)

    MedlinePlus

    ... uses copper as the active contraceptive, others use progesterone in a plastic device. IUDs are very effective ... less than 2% chance per year for the progesterone IUD, less than 1% chance per year for ...

  3. Devices for Arrhythmia

    MedlinePlus

    ... with recurrent arrhythmias, medical devices such as a pacemaker and implantable cardioverter defibrillator (ICD) can help by ... with an ICD Questions to ask your doctor Pacemakers Learn what an artificial pacemaker is, how it ...

  4. Nanowire Thermoelectric Devices

    NASA Technical Reports Server (NTRS)

    Borshchevsky, Alexander; Fleurial, Jean-Pierre; Herman, Jennifer; Ryan, Margaret

    2005-01-01

    Nanowire thermoelectric devices, now under development, are intended to take miniaturization a step beyond the prior state of the art to exploit the potential advantages afforded by shrinking some device features to approximately molecular dimensions (of the order of 10 nm). The development of nanowire-based thermoelectric devices could lead to novel power-generating, cooling, and sensing devices that operate at relatively low currents and high voltages. Recent work on the theory of thermoelectric devices has led to the expectation that the performance of such a device could be enhanced if the diameter of the wires could be reduced to a point where quantum confinement effects increase charge-carrier mobility (thereby increasing the Seebeck coefficient) and reduce thermal conductivity. In addition, even in the absence of these effects, the large aspect ratios (length of the order of tens of microns diameter of the order of tens of nanometers) of nanowires would be conducive to the maintenance of large temperature differences at small heat fluxes. The predicted net effect of reducing diameters to the order of tens of nanometers would be to increase its efficiency by a factor of .3. Nanowires made of thermoelectric materials and devices that comprise arrays of such nanowires can be fabricated by electrochemical growth of the thermoelectric materials in templates that contain suitably dimensioned pores (10 to 100 nm in diameter and 1 to 100 microns long). The nanowires can then be contacted in bundles to form devices that look similar to conventional thermoelectric devices, except that a production version may contain nearly a billion elements (wires) per square centimeter, instead of fewer than a hundred as in a conventional bulk thermoelectric device or fewer than 100,000 as in a microdevice. It is not yet possible to form contacts with individual nanowires. Therefore, in fabricating a nanowire thermoelectric device, one forms contacts on nanowires in bundles of the

  5. Ion funnel device

    SciTech Connect

    Ibrahim, Yehia M.; Chen, Tsung-Chi; Harrer, Marques B.

    2017-11-21

    An ion funnel device is disclosed. A first pair of electrodes is positioned in a first direction. A second pair of electrodes is positioned in a second direction. The device includes an RF voltage source and a DC voltage source. A RF voltage with a superimposed DC voltage gradient is applied to the first pair of electrodes, and a DC voltage gradient is applied to the second pair of electrodes.

  6. Atherectomy devices: technology update

    PubMed Central

    Akkus, Nuri I; Abdulbaki, Abdulrahman; Jimenez, Enrique; Tandon, Neeraj

    2015-01-01

    Atherectomy is a procedure which is performed to remove atherosclerotic plaque from diseased arteries. Atherosclerotic plaques are localized in either coronary or peripheral arterial vasculature and may have different characteristics depending on the texture of the plaque. Atherectomy has been used effectively in treatment of both coronary and peripheral arterial disease. Atherectomy devices are designed differently to either cut, shave, sand, or vaporize these plaques and have different indications. In this article, current atherectomy devices are reviewed. PMID:25565904

  7. Commercialization of microfluidic devices.

    PubMed

    Volpatti, Lisa R; Yetisen, Ali K

    2014-07-01

    Microfluidic devices offer automation and high-throughput screening, and operate at low volumes of consumables. Although microfluidics has the potential to reduce turnaround times and costs for analytical devices, particularly in medical, veterinary, and environmental sciences, this enabling technology has had limited diffusion into consumer products. This article analyzes the microfluidics market, identifies issues, and highlights successful commercialization strategies. Addressing niche markets and establishing compatibility with existing workflows will accelerate market penetration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Raney nickel catalytic device

    DOEpatents

    O'Hare, Stephen A.

    1978-01-01

    A catalytic device for use in a conventional coal gasification process which includes a tubular substrate having secured to its inside surface by expansion a catalytic material. The catalytic device is made by inserting a tubular catalytic element, such as a tubular element of a nickel-aluminum alloy, into a tubular substrate and heat-treating the resulting composite to cause the tubular catalytic element to irreversibly expand against the inside surface of the substrate.

  9. Ferroelectrics for semiconductor devices

    NASA Astrophysics Data System (ADS)

    Sayer, M.; Wu, Z.; Vasant Kumar, C. V. R.; Amm, D. T.; Griswold, E. M.

    1992-11-01

    The technology for the implementation of the integration of thin film ferroelectrics with silicon processing for various devices is described, and factors affecting the integration of ferroelectric films with semiconductor processing are discussed. Consideration is also given to film properties, the properties of electrode materials and structures, and the phenomena of ferroelectric fatigue and aging. Particular attention is given to the nonmemory device application of ferroelectrics.

  10. REACTOR CONTROL DEVICE

    DOEpatents

    Kaufman, H.B.; Weiss, A.A.

    1959-08-18

    A shadow control device for controlling a nuclear reactor is described. The device comprises a series of hollow neutron-absorbing elements arranged in groups, each element having a cavity for substantially housing an adjoining element and a longitudinal member for commonly supporting the groups of elements. Longitudinal actuation of the longitudinal member distributes the elements along its entire length in which position maximum worth is achieved.

  11. Nitinol Temperature Monitoring Devices

    DTIC Science & Technology

    1976-01-09

    AD-A021 578 NITINOL TEMPERATURE MONITORING DEVICES William J. Buehler, et al Naval Surface Weapons Center Silver Spring, Maryland 9 January 1976...LABORATORY S NITINOL TEMPERATURE MONITORING DEVICES 9 JANUARY 1976 NAVAL SURFACE WEAPONS CENTER WHITE OAK LABORATORY SILVER SPRING, MARYLAND 20910 * Approved...GOVT ACCESSION NO. 3. RECIPIIENT’S CATALOG NUMBER NSWC/WOL/TR 75-140 ____ ______ 4 TITLE (and Subtitle) 5. TYPE OF REPCRT & PERIOD COVERED Nitinol

  12. 76 FR 45860 - In the Matter of Certain Electronic Devices, Including Wireless Communication Devices, Portable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-01

    ..., Including Wireless Communication Devices, Portable Music and Data Processing Devices, and Tablet Computers... electronic devices, including wireless communication devices, portable music and data processing devices, and... electronic devices, including wireless communication devices, portable music and data processing devices, and...

  13. Wireless device monitoring systems and monitoring devices, and associated methods

    SciTech Connect

    McCown, Steven H; Derr, Kurt W; Rohde, Kenneth W

    Wireless device monitoring systems and monitoring devices include a communications module for receiving wireless communications of a wireless device. Processing circuitry is coupled with the communications module and configured to process the wireless communications to determine whether the wireless device is authorized or unauthorized to be present at the monitored area based on identification information of the wireless device. Methods of monitoring for the presence and identity of wireless devices are also provided.

  14. Electronic security device

    DOEpatents

    Eschbach, E.A.; LeBlanc, E.J.; Griffin, J.W.

    1992-03-17

    The present invention relates to a security device having a control box containing an electronic system and a communications loop over which the system transmits a signal. The device is constructed so that the communications loop can extend from the control box across the boundary of a portal such as a door into a sealed enclosure into which access is restricted whereby the loop must be damaged or moved in order for an entry to be made into the enclosure. The device is adapted for detecting unauthorized entries into such enclosures such as rooms or containers and for recording the time at which such entries occur for later reference. Additionally, the device detects attempts to tamper or interfere with the operation of the device itself and records the time at which such events take place. In the preferred embodiment, the security device includes a microprocessor-based electronic system and a detection module capable of registering changes in the voltage and phase of the signal transmitted over the loop. 11 figs.

  15. Contamination control device

    DOEpatents

    Clark, Robert M.; Cronin, John C.

    1977-01-01

    A contamination control device for use in a gas-insulated transmission bus consisting of a cylindrical center conductor coaxially mounted within a grounded cylindrical enclosure. The contamination control device is electrically connected to the interior surface of the grounded outer shell and positioned along an axial line at the lowest vertical position thereon. The contamination control device comprises an elongated metallic member having a generally curved cross-section in a first plane perpendicular to the axis of the bus and having an arcuate cross-section in a second plane lying along the axis of the bus. Each opposed end of the metallic member and its opposing sides are tapered to form a pair of generally converging and downward sloping surfaces to trap randomly moving conductive particles in the relatively field-free region between the metallic member and the interior surface of the grounded outer shell. The device may have projecting legs to enable the device to be spot welded to the interior of the grounded housing. The control device provides a high capture probability and prevents subsequent release of the charged particles after the capture thereof.

  16. Electronic security device

    DOEpatents

    Eschbach, Eugene A.; LeBlanc, Edward J.; Griffin, Jeffrey W.

    1992-01-01

    The present invention relates to a security device having a control box (12) containing an electronic system (50) and a communications loop (14) over which the system transmits a signal. The device is constructed so that the communications loop can extend from the control box across the boundary of a portal such as a door into a sealed enclosure into which access is restricted whereby the loop must be damaged or moved in order for an entry to be made into the enclosure. The device is adapted for detecting unauthorized entries into such enclosures such as rooms or containers and for recording the time at which such entries occur for later reference. Additionally, the device detects attempts to tamper or interfere with the operation of the device itself and records the time at which such events take place. In the preferred embodiment, the security device includes a microprocessor-based electronic system (50) and a detection module (72) capable of registering changes in the voltage and phase of the signal transmitted over the loop.

  17. Cardiac rhythm management devices

    PubMed

    Stevenson, Irene; Voskoboinik, Alex

    2018-05-01

    The last decade has seen ongoing evolution and use of cardiac rhythm management devices, including pacemakers, cardiac resynchronisation therapy, implantable cardioverter defibrillators and loop recorders. General practitioners are increasingly involved in follow-up and management of patients with these devices. The aim of this article is to provide an overview of different cardiac rhythm management devices, including their role, implant procedure, post-procedural care, potential complications and follow‑up. We also include practical advice for patients regarding driving, exercise, sexual intimacy and precautions with regards to electromagnetic interference. Cardiac rhythm management devices perform many functions, including bradycardia pacing, monitoring for arrhythmias, cardiac resynchronisation for heart failure, defibrillation and anti-tachycardia pacing for tachyarrhythmias. Concerns regarding potential device-related complications should be discussed with the implanting physician. In the post-implant period, patients with cardiac rhythm management devices can expect to lead normal, active lives. However, caution must occasionally be exercised in certain situations, such as near appliances with electromagnetic interference. Future innovations will move away from transvenous leads to leadless designs with combinations of different components on a 'modular' basis according to the function required.

  18. Device Physics of Contact Issues for the Overestimation and Underestimation of Carrier Mobility in Field-Effect Transistors

    NASA Astrophysics Data System (ADS)

    Liu, Chuan; Li, Gongtan; Di Pietro, Riccardo; Huang, Jie; Noh, Yong-Young; Liu, Xuying; Minari, Takeo

    2017-09-01

    Very high values of carrier mobility have been recently reported in newly developed materials for field-effect transistors (FETs) or thin-film transistors (TFTs). However, there is an increasing concern of whether the values are overestimated. In this paper, we investigate how much contact resistance a FET or TFT can tolerate to allow the conventional current-voltage equations, which is derived for no contact resistance. We contend that mobility in transistors with resistive contact can be underestimated with the presence of the injection barrier, whereas mobility in transistors with gated Schottky contact can be overestimated by more than 10 times. The latter phenomenon occurs even in long-channel devices, and it becomes more severe when using low-k dielectrics. This is because the band bending and injection barrier experience a complicated evolution on account of electrostatic doping in the semiconducting layer; thus, they do not follow a capacitance approximation. When the band bending is weak, the accumulation is as weak as that in the subthreshold regime. Accordingly, the carrier concentration nonlinearly increases with the gate field. This mechanism can occur with or without exhibiting the "kink" feature in the transfer curves, which has been suggested as the signature of overestimation. For precision, carrier mobility should be presented against gate voltage and should be examined by other recommended extraction methods.

  19. Numerical simulation of offset-drain amorphous oxide-based thin-film transistors

    NASA Astrophysics Data System (ADS)

    Jeong, Jaewook

    2016-11-01

    In this study, we analyzed the electrical characteristics of amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) with an offset-drain structure by technology computer aided design (TCAD) simulation. When operating in a linear region, an enhancement-type TFT shows poor field-effect mobility because most conduction electrons are trapped in acceptor-like defects in an offset region when the offset length (L off) exceeds 0.5 µm, whereas a depletion-type TFT shows superior field-effect mobility owing to the high free electron density in the offset region compared with the trapped electron density. When operating in the saturation region, both types of TFTs show good field-effect mobility comparable to that of a reference TFT with a large gate overlap. The underlying physics of the depletion and enhancement types of offset-drain TFTs are systematically analyzed.

  20. Hybrid semiconductor nanomagnetoelectronic devices

    NASA Astrophysics Data System (ADS)

    Bae, Jong Uk

    2007-12-01

    The subject of this dissertation is the exploration of a new class of hybrid semiconductor nanomagnetoelectronic devices. In these studies, single-domain nanomagnets are used as the gate in a transistor structure, and the spatially non-uniform magnetic fields that they generate provide an additional means to modulate the channel conductance. A quantum wire etched in a high-mobility GaAs/AlGaAs quantum well serves as the channel of this device and the current flow through it is modulated by a high-aspect-ratio Co nanomagnet. The conductance of this device exhibits clear hysteresis in a magnetic field, which is significantly enhanced when the nanomagnet is used as a gate to form a local tunnel barrier in the semiconductor channel. A simple theoretical model, which models the tunnel barrier as a simple harmonic saddle, is able to account for the experimentallyobserved behavior. Further improvements in the tunneling magneto-resistance of this device should be possible in the future by optimizing the gate and channel geometries. In addition to these investigations, we have also explored the hysteretic magnetoresistance of devices in which the tunnel barrier is absent and the behavior is instead dominated by the properties of the magnetic barrier alone. We show experimentally how quantum corrections to the conductance of the quantum wire compete against the magneto-transport effects induced by the non-uniform magnetic field.

  1. Spectral tailoring device

    DOEpatents

    Brager, H.R.; Schenter, R.E.; Carter, L.L.; Karnesky, R.A.

    1987-08-05

    A spectral tailoring device for altering the neutron energy spectra and flux of neutrons in a fast reactor thereby selectively to enhance or inhibit the transmutation rate of a target metrical to form a product isotope. Neutron moderators, neutron filters, neutron absorbers and neutron reflectors may be used as spectral tailoring devices. Depending on the intended use for the device, a member from each of these four classes of materials could be used singularly, or in combination, to provide a preferred neutron energy spectra and flux of the neutrons in the region of the target material. In one embodiment of the invention, an assembly is provided for enhancing the production of isotopes, such as cobalt 60 and gadolinium 153. In another embodiment of the invention, a spectral tailoring device is disposed adjacent a target material which comprises long lived or volatile fission products and the device is used to shift the neutron energy spectra and flux of neutrons in the region of the fission products to preferentially transmute them to produce a less volatile fission product inventory. 6 figs.

  2. Electrical apparatus lockout device

    DOEpatents

    Gonzales, Rick

    1999-01-01

    A simple lockout device for electrical equipment equipped with recessed power blades is described. The device comprises a face-plate (12) having a threaded member (14) attached thereto and apertures suitable for accommodating the power blades of a piece of electrical equipment, an elastomeric nose (16) abutting the face-plate having a hole for passage of the threaded member therethrough and power blade apertures in registration with those of the face-plate, a block (20) having a recess (34) in its forward face for receiving at least a portion of the hose, a hole therein for receiving the threaded member and an integral extension (26) extending from its rear face. A thumb screw (22) suitable for turning with the hands and having internal threads suitable for engaging the threaded member attached to the face-plate is inserted into a passage in the integral extension to engage the threaded member in such a fashion that when the device is inserted over the recessed power blades of a piece of electrical equipment and the thumb screw (22) tightened, the elastomeric nose (16) is compressed between the face-plate (12) and the block (20) forcing it to expand laterally thereby securing the device in the recess and precluding the accidental or intentional energization of the piece of equipment by attachment of a power cord to the recessed power blades. Means are provided in the interval extension and the thumb screw for the attachment of a locking device (46) which will satisfy OSHA standards.

  3. Scalability of carbon-nanotube-based thin film transistors for flexible electronic devices manufactured using an all roll-to-roll gravure printing system

    PubMed Central

    Koo, Hyunmo; Lee, Wookyu; Choi, Younchang; Sun, Junfeng; Bak, Jina; Noh, Jinsoo; Subramanian, Vivek; Azuma, Yasuo; Majima, Yutaka; Cho, Gyoujin

    2015-01-01

    To demonstrate that roll-to-roll (R2R) gravure printing is a suitable advanced manufacturing method for flexible thin film transistor (TFT)-based electronic circuits, three different nanomaterial-based inks (silver nanoparticles, BaTiO3 nanoparticles and single-walled carbon nanotubes (SWNTs)) were selected and optimized to enable the realization of fully printed SWNT-based TFTs (SWNT-TFTs) on 150-m-long rolls of 0.25-m-wide poly(ethylene terephthalate) (PET). SWNT-TFTs with 5 different channel lengths, namely, 30, 80, 130, 180, and 230 μm, were fabricated using a printing speed of 8 m/min. These SWNT-TFTs were characterized, and the obtained electrical parameters were related to major mechanical factors such as web tension, registration accuracy, impression roll pressure and printing speed to determine whether these mechanical factors were the sources of the observed device-to-device variations. By utilizing the electrical parameters from the SWNT-TFTs, a Monte Carlo simulation for a 1-bit adder circuit, as a reference, was conducted to demonstrate that functional circuits with reasonable complexity can indeed be manufactured using R2R gravure printing. The simulation results suggest that circuits with complexity, similar to the full adder circuit, can be printed with a 76% circuit yield if threshold voltage (Vth) variations of less than 30% can be maintained. PMID:26411839

  4. Pendulum detector testing device

    DOEpatents

    Gonsalves, J.M.

    1997-09-30

    A detector testing device is described which provides consistent, cost-effective, repeatable results. The testing device is primarily constructed of PVC plastic and other non-metallic materials. Sensitivity of a walk-through detector system can be checked by: (1) providing a standard test object simulating the mass, size and material content of a weapon or other contraband, (2) suspending the test object in successive positions, such as head, waist and ankle levels, simulating where the contraband might be concealed on a person walking through the detector system; and (3) swinging the suspended object through each of the positions, while operating the detector system and observing its response. The test object is retained in a holder in which the orientation of the test device or target can be readily changed, to properly complete the testing requirements. 5 figs.

  5. Pendulum detector testing device

    DOEpatents

    Gonsalves, John M.

    1997-01-01

    A detector testing device which provides consistent, cost-effective, repeatable results. The testing device is primarily constructed of PVC plastic and other non-metallic materials. Sensitivity of a walk-through detector system can be checked by: 1) providing a standard test object simulating the mass, size and material content of a weapon or other contraband, 2) suspending the test object in successive positions, such as head, waist and ankle levels, simulating where the contraband might be concealed on a person walking through the detector system; and 3) swinging the suspended object through each of the positions, while operating the detector system and observing its response. The test object is retained in a holder in which the orientation of the test device or target can be readily changed, to properly complete the testing requirements.

  6. Ion manipulation device

    SciTech Connect

    Anderson, Gordon A.; Baker, Erin M.; Smith, Richard D.

    2018-05-08

    An ion manipulation method and device is disclosed. The device includes a pair of substantially parallel surfaces. An array of inner electrodes is contained within, and extends substantially along the length of, each parallel surface. The device includes a first outer array of electrodes and a second outer array of electrodes. Each outer array of electrodes is positioned on either side of the inner electrodes, and is contained within and extends substantially along the length of each parallel surface. A DC voltage is applied to the first and second outer array of electrodes. A RF voltage, with a superimposed electricmore » field, is applied to the inner electrodes by applying the DC voltages to each electrode. Ions either move between the parallel surfaces within an ion confinement area or along paths in the direction of the electric field, or can be trapped in the ion confinement area.« less

  7. Fragment capture device

    SciTech Connect

    Payne, Lloyd R.; Cole, David L.

    2010-03-30

    A fragment capture device for use in explosive containment. The device comprises an assembly of at least two rows of bars positioned to eliminate line-of-sight trajectories between the generation point of fragments and a surrounding containment vessel or asset. The device comprises an array of at least two rows of bars, wherein each row is staggered with respect to the adjacent row, and wherein a lateral dimension of each bar and a relative position of each bar in combination provides blockage of a straight-line passage of a solid fragment through the adjacent rows of bars, wherein a generation point ofmore » the solid fragment is located within a cavity at least partially enclosed by the array of bars.« less

  8. Registration of Medical Devices

    PubMed Central

    George, Bobby

    2010-01-01

    Globally the medical device (MD) market has been growing quite rapidly over the past decade. The regulatory framework for pharmaceuticals and devices differ substantially. The regulatory authorities in different regions of the world recognize different classes of medical devices (MDs), based on their design complexity, their use characteristics, and their potential for harm, if misused. With the vast majority of MDs in developing countries being imported, the respective governments need to put in place policies & regulations to address all elements related to MDs, ranging from its development, manufacturing, registration to post-marketing obligations & disposal so that public can have access to high quality, safe & affordable products for appropriate use. This article highlights current regulations pertaining to registration of MDs in India, in light of those existing in Global Harmonization Task Force (GHTF) member countries & Association of Southeast Asian Nations (ASEAN) countries. PMID:21814626

  9. Fragment capture device

    DOEpatents

    Payne, Lloyd R.; Cole, David L.

    2010-03-30

    A fragment capture device for use in explosive containment. The device comprises an assembly of at least two rows of bars positioned to eliminate line-of-sight trajectories between the generation point of fragments and a surrounding containment vessel or asset. The device comprises an array of at least two rows of bars, wherein each row is staggered with respect to the adjacent row, and wherein a lateral dimension of each bar and a relative position of each bar in combination provides blockage of a straight-line passage of a solid fragment through the adjacent rows of bars, wherein a generation point of the solid fragment is located within a cavity at least partially enclosed by the array of bars.

  10. Laser device and method

    SciTech Connect

    Myers, J. D.

    1985-06-25

    A simplified, relatively inexpensive laser device, wherein the laser elements are fixed in a body exoskeleton of electrical insulating material having a low coefficient of thermal expansion. The preferred embodiment includes a shotgun type laser filter having parallel bores which receive the laser flashlamp and laser rod in fixed relation in a body chamber. The reflector surrounds the laser filter and retains the filter within the body chamber. In the preferred method of this invention, several controlled lasing pulses are generated with each illumination pulse of the flashlamp, substantially increasing the efficiency of the laser device. The number of pulsesmore » is generally controlled by increasing the voltage to the flashlamp. The rapid multiple lasing pulses generate an elongated plasma in a fluid medium, such as the vitreous fluid body of an eye which makes the laser device extemely efficient for treating glaucoma and other medical treatments.« less

  11. Electrochromic optical switching device

    DOEpatents

    Lampert, C.M.; Visco, S.J.

    1992-08-25

    An electrochromic cell is disclosed which comprises an electrochromic layer, a polymerizable organo-sulfur layer which comprises the counter electrode of the structure, and an ionically conductive electronically insulating material which comprises the separator between the electrodes. In a preferred embodiment, both the separator and the organo-sulfur electrode (in both its charged and uncharged states) are transparent either to visible light or to the entire solar spectrum. An electrochromic device is disclosed which comprises such electrodes and separator encased in glass plates on the inner surface of each of which is formed a transparent electrically conductive film in respective electrical contact with the electrodes which facilitates formation of an external electrical connection or contact to the electrodes of the device to permit electrical connection of the device to an external potential source. 3 figs.

  12. Evaporative Cooling Membrane Device

    NASA Technical Reports Server (NTRS)

    Lomax, Curtis (Inventor); Moskito, John (Inventor)

    1999-01-01

    An evaporative cooling membrane device is disclosed having a flat or pleated plate housing with an enclosed bottom and an exposed top that is covered with at least one sheet of hydrophobic porous material having a thin thickness so as to serve as a membrane. The hydrophobic porous material has pores with predetermined dimensions so as to resist any fluid in its liquid state from passing therethrough but to allow passage of the fluid in its vapor state, thereby, causing the evaporation of the fluid and the cooling of the remaining fluid. The fluid has a predetermined flow rate. The evaporative cooling membrane device has a channel which is sized in cooperation with the predetermined flow rate of the fluid so as to produce laminar flow therein. The evaporative cooling membrane device provides for the convenient control of the evaporation rates of the circulating fluid by adjusting the flow rates of the laminar flowing fluid.

  13. Endoscopic Devices for Obesity.

    PubMed

    Sampath, Kartik; Dinani, Amreen M; Rothstein, Richard I

    2016-06-01

    The obesity epidemic, recognized by the World Health Organization in 1997, refers to the rising incidence of obesity worldwide. Lifestyle modification and pharmacotherapy are often ineffective long-term solutions; bariatric surgery remains the gold standard for long-term obesity weight loss. Despite the reported benefits, it has been estimated that only 1% of obese patients will undergo surgery. Endoscopic treatment for obesity represents a potential cost-effective, accessible, minimally invasive procedure that can function as a bridge or alternative intervention to bariatric surgery. We review the current endoscopic bariatric devices including space occupying devices, endoscopic gastroplasty, aspiration technology, post-bariatric surgery endoscopic revision, and obesity-related NOTES procedures. Given the diverse devices already FDA approved and in development, we discuss the future directions of endoscopic therapies for obesity.

  14. Regenerative combustion device

    DOEpatents

    West, Phillip B.

    2004-03-16

    A regenerative combustion device having a combustion zone, and chemicals contained within the combustion zone, such as water, having a first equilibrium state, and a second combustible state. Means for transforming the chemicals from the first equilibrium state to the second combustible state, such as electrodes, are disposed within the chemicals. An igniter, such as a spark plug or similar device, is disposed within the combustion zone for igniting combustion of the chemicals in the second combustible state. The combustion products are contained within the combustion zone, and the chemicals are selected such that the combustion products naturally chemically revert into the chemicals in the first equilibrium state following combustion. The combustion device may thus be repeatedly reused, requiring only a brief wait after each ignition to allow the regeneration of combustible gasses within the head space.

  15. Biochip scanner device

    DOEpatents

    Perov, Alexander; Belgovskiy, Alexander I.; Mirzabekov, Andrei D.

    2001-01-01

    A biochip scanner device used to detect and acquire fluorescence signal data from biological microchips or biochips and method of use are provided. The biochip scanner device includes a laser for emitting a laser beam. A modulator, such as an optical chopper modulates the laser beam. A scanning head receives the modulated laser beam and a scanning mechanics coupled to the scanning head moves the scanning head relative to the biochip. An optical fiber delivers the modulated laser beam to the scanning head. The scanning head collects the fluorescence light from the biochip, launches it into the same optical fiber, which delivers the fluorescence into a photodetector, such as a photodiode. The biochip scanner device is used in a row scanning method to scan selected rows of the biochip with the laser beam size matching the size of the immobilization site.

  16. Nonimaging radiant energy device

    DOEpatents

    Winston, Roland; Ning, Xiaohui

    1993-01-01

    A nonimaging radiant energy device may include a hyperbolically shaped reflective element with a radiant energy inlet and a radiant energy outlet. A convex lens is provided at the radiant energy inlet and a concave lens is provided at the radiant energy outlet. Due to the provision of the lenses and the shape of the walls of the reflective element, the radiant energy incident at the radiant energy inlet within a predetermined angle of acceptance is emitted from the radiant energy outlet exclusively within an acute exit angle. In another embodiment, the radiant energy device may include two interconnected hyperbolically shaped reflective elements with a respective convex lens being provided at each aperture of the device.

  17. Nonimaging radiant energy device

    DOEpatents

    Winston, Roland; Ning, Xiaohui

    1996-01-01

    A nonimaging radiant energy device may include a hyperbolically shaped reflective element with a radiant energy inlet and a radiant energy outlet. A convex lens is provided at the radiant energy inlet and a concave lens is provided at the radiant energy outlet. Due to the provision of the lenses and the shape of the walls of the reflective element, the radiant energy incident at the radiant energy inlet within a predetermined angle of acceptance is emitted from the radiant energy outlet exclusively within an acute exit angle. In another embodiment, the radiant energy device may include two interconnected hyperbolically shaped reflective elements with a respective convex lens being provided at each aperture of the device.

  18. REACTOR CONTROL DEVICE

    DOEpatents

    Graham, R.H.

    1962-09-01

    A wholly mechanical compact control device is designed for automatically rendering the core of a fission reactor subcritical in response to core temperatures in excess of the design operating temperature limit. The control device comprises an expansible bellows interposed between the base of a channel in a reactor core and the inner end of a fuel cylinder therein which is normally resiliently urged inwardly. The bellows contains a working fluid which undergoes a liquid to vapor phase change at a temperature substantially equal to the design temperature limit. Hence, the bellows abruptiy expands at this limiting temperature to force the fuel cylinder outward and render the core subcritical. The control device is particularly applicable to aircraft propulsion reactor service. (AEC)

  19. Electrochromic optical switching device

    DOEpatents

    Lampert, Carl M.; Visco, Steven J.

    1992-01-01

    An electrochromic cell is disclosed which comprises an electrochromic layer, a polymerizable organo-sulfur layer which comprises the counter electrode of the structure, and an ionically conductive electronically insulating material which comprises the separator between the electrodes. In a preferred embodiment, both the separator and the organo-sulfur electrode (in both its charged and uncharged states) are transparent either to visible light or to the entire solar spectrum. An electrochromic device is disclosed which comprises such electrodes and separator encased in glass plates on the inner surface of each of which is formed a transparent electrically conductive film in respective electrical contact with the electrodes which facilitates formation of an external electrical connection or contact to the electrodes of the device to permit electrical connection of the device to an external potential source.

  20. Nonaqueous Electrical Storage Device

    DOEpatents

    McEwen, Alan B.; Evans, David A.; Blakley, Thomas J.; Goldman, Jay L.

    1999-10-26

    An electrochemical capacitor is disclosed that features two, separated, high surface area carbon cloth electrodes sandwiched between two current collectors fabricated of a conductive polymer having a flow temperature greater than 130.degree. C., the perimeter of the electrochemical capacitor being sealed with a high temperature gasket to form a single cell device. The gasket material is a thermoplastic stable at temperatures greater than 100.degree. C., preferably a polyester or a polyurethane, and having a reflow temperature above 130.degree. C. but below the softening temperature of the current collector material. The capacitor packaging has good mechanical integrity over a wide temperature range, contributes little to the device equivalent series resistance (ESR), and is stable at high potentials. In addition, the packaging is designed to be easily manufacturable by assembly line methods. The individual cells can be stacked in parallel or series configuration to reach the desired device voltage and capacitance.

  1. Therapeutic Devices for Epilepsy

    PubMed Central

    Fisher, Robert S.

    2011-01-01

    Therapeutic devices provide new options for treating drug-resistant epilepsy. These devices act by a variety of mechanisms to modulate neuronal activity. Only vagus nerve stimulation, which continues to develop new technology, is approved for use in the United States. Deep brain stimulation (DBS) of anterior thalamus for partial epilepsy recently was approved in Europe and several other countries. Responsive neurostimulation, which delivers stimuli to one or two seizure foci in response to a detected seizure, recently completed a successful multicenter trial. Several other trials of brain stimulation are in planning or underway. Transcutaneous magnetic stimulation (TMS) may provide a noninvasive method to stimulate cortex. Controlled studies of TMS split on efficacy, and may depend on whether a seizure focus is near a possible region for stimulation. Seizure detection devices in the form of “shake” detectors via portable accelerometers can provide notification of an ongoing tonic-clonic seizure, or peace of mind in the absence of notification. Prediction of seizures from various aspects of EEG is in early stages. Prediction appears to be possible in a subpopulation of people with refractory seizures and a clinical trial of an implantable prediction device is underway. Cooling of neocortex or hippocampus reversibly can attenuate epileptiform EEG activity and seizures, but engineering problems remain in its implementation. Optogenetics is a new technique that can control excitability of specific populations of neurons with light. Inhibition of epileptiform activity has been demonstrated in hippocampal slices, but use in humans will require more work. In general, devices provide useful palliation for otherwise uncontrollable seizures, but with a different risk profile than with most drugs. Optimizing the place of devices in therapy for epilepsy will require further development and clinical experience. PMID:22367987

  2. Precision alignment device

    DOEpatents

    Jones, Nelson E.

    1990-01-01

    Apparatus for providing automatic alignment of beam devices having an associated structure for directing, collimating, focusing, reflecting, or otherwise modifying the main beam. A reference laser is attached to the structure enclosing the main beam producing apparatus and produces a reference beam substantially parallel to the main beam. Detector modules containing optical switching devices and optical detectors are positioned in the path of the reference beam and are effective to produce an electrical output indicative of the alignment of the main beam. This electrical output drives servomotor operated adjustment screws to adjust the position of elements of the structure associated with the main beam to maintain alignment of the main beam.

  3. REMOTE CONTROLLED SWITCHING DEVICE

    DOEpatents

    Hobbs, J.C.

    1959-02-01

    An electrical switching device which can be remotely controlled and in which one or more switches may be accurately operated at predetermined times or with predetermined intervening time intervals is described. The switching device consists essentially of a deck, a post projecting from the deck at right angles thereto, cam means mounted for rotation around said posts and a switch connected to said deck and actuated by said cam means. Means is provided for rotating the cam means at a constant speed and the switching apparatus is enclosed in a sealed container with external adjusting means and electrical connection elements.

  4. EXPERIMENTAL ANIMAL WATERING DEVICE

    DOEpatents

    Finkel, M.P.

    1964-04-01

    A device for watering experimental animals confined in a battery of individual plastic enclosures is described. It consists of a rectangular plastic enclosure having a plurality of fluid-tight compartments, each with a drinking hole near the bottom and a filling hole on the top. The enclosure is immersed in water until filled, its drinking holes sealed with a strip of tape, and it is then placed in the battery. The tape sealing prevents the flow of water from the device, but permits animals to drink by licking the drinking holes. (AEC)

  5. ROTATING PLASMA DEVICE

    DOEpatents

    Boyer, K.; Hammel, J.E.; Longmire, C.L.; Nagle, D.E.; Ribe, F.L.; Tuck, J.L.

    1961-10-24

    ABS>A method and device are described for obtaining fusion reactions. The basic concept is that of using crossed electric and magnetic fields to induce a plasma rotation in which the ionized particles follow a circumferential drift orbit on wldch a cyclotron mode of motion is superimposed, the net result being a cycloidal motion about the axis of symmetry. The discharge tube has a radial electric field and a longitudinal magnetic field. Mirror machine geometry is utilized. The device avoids reliance on the pinch effect and its associated instability problems. (AEC)

  6. Heat transfer device

    NASA Technical Reports Server (NTRS)

    Eaton, L. R. (Inventor)

    1976-01-01

    An improved heat transfer device particularly suited for use as an evaporator plate in a diffusion cloud chamber. The device is characterized by a pair of mutually spaced heat transfer plates, each being of a planar configuration, having a pair of opposed surfaces defining therebetween a heat pipe chamber. Within the heat pipe chamber, in contiguous relation with the pair of opposed surfaces, there is disposed a pair of heat pipe wicks supported in a mutually spaced relationship by a foraminous spacer of a planar configuration. A wick including a foraminous layer is contiguously related to the external surfaces of the heat transfer plates for uniformly wetting these surfaces.

  7. Microfluidic Cell Culture Device

    NASA Technical Reports Server (NTRS)

    Takayama, Shuichi (Inventor); Cabrera, Lourdes Marcella (Inventor); Heo, Yun Seok (Inventor); Smith, Gary Daniel (Inventor)

    2014-01-01

    Microfluidic devices for cell culturing and methods for using the same are disclosed. One device includes a substrate and membrane. The substrate includes a reservoir in fluid communication with a passage. A bio-compatible fluid may be added to the reservoir and passage. The reservoir is configured to receive and retain at least a portion of a cell mass. The membrane acts as a barrier to evaporation of the bio-compatible fluid from the passage. A cover fluid may be added to cover the bio-compatible fluid to prevent evaporation of the bio-compatible fluid.

  8. Novel Magnetic Devices

    DTIC Science & Technology

    2007-10-12

    Vincent, Magnetism Magnetic Materials (LAW3MO5), Vifia del Mar, Chile, December 11-15, 2005. 5. Nanomagnetism, Ivan K. Schuller, Pan America Advanced Study Institute, PASI 2007, Zacatecas , Mexico , June 19, 2007. 6 ...project explored the design, preparation, measurement and theoretical study of these novel magnetic devices. Modem thin film techniques (sputtering and...results to motion associated with the unstable nature of mechanical contacts In order to exploit BMR from a device point of view (or to make it useful in a

  9. Phononic crystal devices

    DOEpatents

    El-Kady, Ihab F [Albuquerque, NM; Olsson, Roy H [Albuquerque, NM

    2012-01-10

    Phononic crystals that have the ability to modify and control the thermal black body phonon distribution and the phonon component of heat transport in a solid. In particular, the thermal conductivity and heat capacity can be modified by altering the phonon density of states in a phononic crystal. The present invention is directed to phononic crystal devices and materials such as radio frequency (RF) tags powered from ambient heat, dielectrics with extremely low thermal conductivity, thermoelectric materials with a higher ratio of electrical-to-thermal conductivity, materials with phononically engineered heat capacity, phononic crystal waveguides that enable accelerated cooling, and a variety of low temperature application devices.

  10. Precision alignment device

    DOEpatents

    Jones, N.E.

    1988-03-10

    Apparatus for providing automatic alignment of beam devices having an associated structure for directing, collimating, focusing, reflecting, or otherwise modifying the main beam. A reference laser is attached to the structure enclosing the main beam producing apparatus and produces a reference beam substantially parallel to the main beam. Detector modules containing optical switching devices and optical detectors are positioned in the path of the reference beam and are effective to produce an electrical output indicative of the alignment of the main beam. This electrical output drives servomotor operated adjustment screws to adjust the position of elements of the structure associated with the main beam to maintain alignment of the main beam. 5 figs.

  11. Precision positioning device

    DOEpatents

    McInroy, John E.

    2005-01-18

    A precision positioning device is provided. The precision positioning device comprises a precision measuring/vibration isolation mechanism. A first plate is provided with the precision measuring mean secured to the first plate. A second plate is secured to the first plate. A third plate is secured to the second plate with the first plate being positioned between the second plate and the third plate. A fourth plate is secured to the third plate with the second plate being positioned between the third plate and the fourth plate. An adjusting mechanism for adjusting the position of the first plate, the second plate, the third plate, and the fourth plate relative to each other.

  12. Contaminate Control Device

    NASA Technical Reports Server (NTRS)

    Howe, Robert H. (Inventor); Flynn, Kenneth P. (Inventor); Stapleton, Thomas J. (Inventor)

    2014-01-01

    A contaminate control device for filtering contaminates from a gas such as air is provided. The device includes a housing having a first inlet and a first outlet. An axial flow filter is fluidly coupled between the first inlet and the first outlet, the axial flow filter has a second inlet and a second outlet. A second filter disposed about the axial flow filter and is fluidly coupled between the first inlet and the first outlet, the second filter having a third inlet on an inner diameter and a third outlet disposed on an outer diameter. A flow restrictor is fluidly coupled between the second inlet and the first inlet.

  13. Rooting an Android Device

    DTIC Science & Technology

    2015-09-01

    Hat Enterprise Linux, version 6.5 • Android Development Tools (ADT), version 22.3.0-887826 • Saferoot1 • Samsung Galaxy S3 • Dell Precision T7400...method used for the Samsung Galaxy S3 is called Saferoot1—a well- known, open- source software. According to the Saferoot website, the process of...is applicable for the Samsung Galaxy S3 as well as many other Android devices, but there are several steps involved in rooting an Android device (as

  14. Portable emittance measurement device

    SciTech Connect

    Liakin, D.; Seleznev, D.; Orlov, A.

    2010-02-15

    In Institute for Theoretical and Experimental Physics (ITEP) the portable emittance measurements device is developed. It provides emittance measurements both with ''pepper-pot'' and ''two slits'' methods. Depending on the method of measurements, either slits or pepper-pot mask with scintillator are mounted on the two activators and are installed in two standard Balzer's cross chamber with CF-100 flanges. To match the angle resolution for measured beam, the length of the stainless steel pipe between two crosses changes is adjusted. The description of the device and results of emittance measurements at the ITEP ion source test bench are presented.

  15. Materials for electrochemical device safety

    DOEpatents

    Vissers, Daniel R.; Amine, Khalil; Thackeray, Michael M.; Kahaian, Arthur J.; Johnson, Christopher S.

    2015-04-07

    An electrochemical device includes a thermally-triggered intumescent material or a gas-triggered intumescent material. Such devices prevent or minimize short circuits in a device that could lead to thermal run-away. Such devices may include batteries or supercapacitors.

  16. RADIO RANGING DEVICE

    DOEpatents

    Nieset, R.T.

    1961-05-16

    A radio ranging device is described. It utilizes a super regenerative detector-oscillator in which echoes of transmitted pulses are received in proper phase to reduce noise energy at a selected range and also at multiples of the selected range.

  17. RADIO RANGING DEVICE

    DOEpatents

    Bogle, R.W.

    1960-11-22

    A description is given of a super-regenerative oscillator ranging device provided with radiating and receiving means and being capable of indicating the occurrence of that distance between itself and a reflecting object which so phases the received echo of energy of a preceding emitted oscillation that the intervals between oscillations become uniform.

  18. Human performance measuring device

    NASA Technical Reports Server (NTRS)

    Michael, J.; Scow, J.

    1970-01-01

    Complex coordinator, consisting of operator control console, recorder, subject display panel, and limb controls, measures human performance by testing perceptual and motor skills. Device measures psychophysiological functions in drug and environmental studies, and is applicable to early detection of psychophysiological body changes.

  19. Road-Cleaning Device

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2014-01-01

    Roadways are literally soaked with petrochemical byproducts, oils, gasoline, and other volatile substances that eventually run off into sewers and end up in rivers, waterways, and other undesirable places. Can the roads be cleaned of these wastes, with their proper disposal? Can vehicles, robots, or other devices be designed that could be driven…

  20. Device Oriented Project Controller

    SciTech Connect

    Dalesio, Leo; Kraimer, Martin

    2013-11-20

    This proposal is directed at the issue of developing control systems for very large HEP projects. A de-facto standard in accelerator control is the Experimental Physics and Industrial Control System (EPICS), which has been applied successfully to many physics projects. EPICS is a channel based system that requires that each channel of each device be configured and controlled. In Phase I, the feasibility of a device oriented extension to the distributed channel database was demonstrated by prototyping a device aware version of an EPICS I/O controller that functions with the current version of the channel access communication protocol. Extensions havemore » been made to the grammar to define the database. Only a multi-stage position controller with limit switches was developed in the demonstration, but the grammar should support a full range of functional record types. In phase II, a full set of record types will be developed to support all existing record types, a set of process control functions for closed loop control, and support for experimental beam line control. A tool to configure these records will be developed. A communication protocol will be developed or extensions will be made to Channel Access to support introspection of components of a device. Performance bench marks will be made on both communication protocol and the database. After these records and performance tests are under way, a second of the grammar will be undertaken.« less

  1. Programmable ubiquitous telerobotic devices

    NASA Astrophysics Data System (ADS)

    Doherty, Michael; Greene, Matthew; Keaton, David; Och, Christian; Seidl, Matthew L.; Waite, William; Zorn, Benjamin G.

    1997-12-01

    We are investigating a field of research that we call ubiquitous telepresence, which involves the design and implementation of low-cost robotic devices that can be programmed and operated from anywhere on the Internet. These devices, which we call ubots, can be used for academic purposes (e.g., a biologist could remote conduct a population survey), commercial purposes (e.g., a house could be shown remotely by a real-estate agent), and for recreation and education (e.g., someone could tour a museum remotely). We anticipate that such devices will become increasingly common due to recent changes in hardware and software technology. In particular, current hardware technology enables such devices to be constructed very cheaply (less than $500), and current software and network technology allows highly portable code to be written and downloaded across the Internet. In this paper, we present our prototype system architecture, and the ubot implementation we have constructed based on it. The hardware technology we use is the handy board, a 6811-based controller board with digital and analog inputs and outputs. Our software includes a network layer based on TCP/IP and software layers written in Java. Our software enables users across the Internet to program the behavior of the vehicle and to receive image feedback from a camera mounted on it.

  2. Superlattice optical device

    DOEpatents

    Biefeld, R.M.; Fritz, I.J.; Gourley, P.L.; Osbourn, G.C.

    A semiconductor optical device which includes a superlattice having direct transitions between conduction band and valence band states with the same wave vector, the superlattice being formed from a plurality of alternating layers of two or more different materials, at least the material with the smallest bandgap being an indirect bandgap material.

  3. Color identification testing device

    NASA Technical Reports Server (NTRS)

    Brawner, E. L.; Martin, R.; Pate, W.

    1970-01-01

    Testing device, which determines ability of a technician to identify color-coded electric wires, is superior to standard color blindness tests. It tests speed of wire selection, detects partial color blindness, allows rapid testing, and may be administered by a color blind person.

  4. Electron beam device

    DOEpatents

    Beckner, E.H.; Clauser, M.J.

    1975-08-12

    This patent pertains to an electron beam device in which a hollow target is symmetrically irradiated by a high energy, pulsed electron beam about its periphery and wherein the outer portion of the target has a thickness slightly greater than required to absorb the electron beam pulse energy. (auth)

  5. LOADING AND UNLOADING DEVICE

    DOEpatents

    Treshow, M.

    1960-08-16

    A device for loading and unloading fuel rods into and from a reactor tank through an access hole includes parallel links carrying a gripper. These links enable the gripper to go through the access hole and then to be moved laterally from the axis of the access hole to the various locations of the fuel rods in the reactor tank.

  6. Solar Innovator | Alta Devices

    ScienceCinema

    Mattos, Laila; Le, Minh

    2017-12-09

    Selected to participate in the Energy Department's SunShot Initiative, Alta Devices produces solar cells that convert sunlight into electricity at world record-breaking levels of efficiency. Through its innovative solar technology Alta is helping bring down the cost of solar. Learn more about the Energy Department's efforts to advance solar technology at energy.gov/solar .

  7. Condensate removal device

    DOEpatents

    Maddox, James W.; Berger, David D.

    1984-01-01

    A condensate removal device is disclosed which incorporates a strainer in unit with an orifice. The strainer is cylindrical with its longitudinal axis transverse to that of the vapor conduit in which it is mounted. The orifice is positioned inside the strainer proximate the end which is remoter from the vapor conduit.

  8. Medical device development.

    PubMed

    Panescu, Dorin

    2009-01-01

    The development of a successful medical product requires not only engineering design efforts, but also clinical, regulatory, marketing and business expertise. This paper reviews items related to the process of designing medical devices. It discusses the steps required to take a medical product idea from concept, through development, verification and validation, regulatory approvals and market release.

  9. Multiple gap photovoltaic device

    DOEpatents

    Dalal, Vikram L.

    1981-01-01

    A multiple gap photovoltaic device having a transparent electrical contact adjacent a first cell which in turn is adjacent a second cell on an opaque electrical contact, includes utilizing an amorphous semiconductor as the first cell and a crystalline semiconductor as the second cell.

  10. Electrical Sensing Devices.

    ERIC Educational Resources Information Center

    Montana State Univ., Bozeman. Dept. of Agricultural and Industrial Education.

    This unit of instruction on electrical sensing devices is designed especially for use with freshman vocational agriculture students. A unit plan discusses the general aims and goals, lesson titles, student and teacher activities, and references. The unit consists of four lessons. A lesson plan for each lesson provides these components: need;…

  11. Solid-State Devices.

    ERIC Educational Resources Information Center

    Sutliff, Ronald D.; And Others

    This self-study course is designed to familiarize Marine Corps enlisted personnel with the principles of solid-state devices and their functions. The course contains four study units. Each study unit begins with a general objective, which is a statement of what the student should learn from the unit. The study units are divided into numbered work…

  12. ANNULAR IMPACTOR SAMPLING DEVICE

    DOEpatents

    Tait, G.W.C.

    1959-03-31

    A high-rate air sampler capable of sampling alphaemitting particles as small as 0.5 microns is described. The device is a cylindrical shaped cup that fits in front of a suction tube and which has sticky grease coating along its base. Suction forces contaminated air against the periodically monitored particle absorbing grease.

  13. Cascaded thermoacoustic devices

    DOEpatents

    Swift, Gregory W.; Backhaus, Scott N.; Gardner, David L.

    2003-12-09

    A thermoacoustic device is formed with a resonator system defining at least one region of high specific acoustic impedance in an acoustic wave within the resonator system. A plurality of thermoacoustic units are cascaded together within the region of high specific acoustic impedance, where at least one of the thermoacoustic units is a regenerator unit.

  14. Standardization of splash device

    NASA Astrophysics Data System (ADS)

    Fernández Raga, María; Peters, Piet

    2017-04-01

    The erosion is a complex process that has been studied extensively by numerous researchers, requiring a prolongued time effort and a large economic investment. To be effective, the measurements of erosion should be precise, controlled and replicable, and to assure efectiveness, measurement devices of erosion should be properly designed, constructed, well calibrated and also they should be operated by a trained person (Stroosnijder, 2005). Because researchers try to improve old devices, the equipment is constantly being redesigned, making the measurements not comparable and furthermore, producing a lack of available standarized device. The lack of standardization of erosion equipment is more obvious in the case of the local splash erosion, where the nature of the process makes very difficult to isolate its effects. In this article we compare the results obtained from five of the most common splash erosion devices (selected from more than 16 different currently types), under the same rain conditions, with the objective of facilitate the standardization of the method that will be more easy to build, minimizing the error. A set of six splash devices were setted in well known positions under simulated rain, to measured the differences, among devices and the accuracy of the data recovered after 10 minutes of rainfall simulation under different intensities (from 60 to 130 mm/h). The rainfall simulator of Wageningen was used, using sand as splash erosion source. Differences in the infiltration were also measured, and a calibration of sizes and speeds of the raindrops was done using the photography method (Hamidreza-Sadeghi et al., 2013). The splash devices selected for this study were unbounded splash devices (like the funnel, the cup (Fernandez-Raga et al., 2010) and the splash flume (Jomaa et al., 2010)), and bounded devices that allow the calculation of splash rate, (like the new cup (Scholten et al., 2011) and the Morgan tray). The behaviour of different splash devices

  15. Electronic Devices Based on Oxide Thin Films Fabricated by Fiber-to-Film Process.

    PubMed

    Meng, You; Liu, Ao; Guo, Zidong; Liu, Guoxia; Shin, Byoungchul; Noh, Yong-Young; Fortunato, Elvira; Martins, Rodrigo; Shan, Fukai

    2018-05-30

    Technical development for thin-film fabrication is essential for emerging metal-oxide (MO) electronics. Although impressive progress has been achieved in fabricating MO thin films, the challenges still remain. Here, we report a versatile and general thermal-induced nanomelting technique for fabricating MO thin films from the fiber networks, briefly called fiber-to-film (FTF) process. The high quality of the FTF-processed MO thin films was confirmed by various investigations. The FTF process is generally applicable to numerous technologically relevant MO thin films, including semiconducting thin films (e.g., In 2 O 3 , InZnO, and InZrZnO), conducting thin films (e.g., InSnO), and insulating thin films (e.g., AlO x ). By optimizing the fabrication process, In 2 O 3 /AlO x thin-film transistors (TFTs) were successfully integrated by fully FTF processes. High-performance TFT was achieved with an average mobility of ∼25 cm 2 /(Vs), an on/off current ratio of ∼10 7 , a threshold voltage of ∼1 V, and a device yield of 100%. As a proof of concept, one-transistor-driven pixel circuit was constructed, which exhibited high controllability over the light-emitting diodes. Logic gates based on fully FTF-processed In 2 O 3 /AlO x TFTs were further realized, which exhibited good dynamic logic responses and voltage amplification by a factor of ∼4. The FTF technique presented here offers great potential in large-area and low-cost manufacturing for flexible oxide electronics.

  16. Simple method to enhance positive bias stress stability of In-Ga-Zn-O thin-film transistors using a vertically graded oxygen-vacancy active layer.

    PubMed

    Park, Ji Hoon; Kim, Yeong-Gyu; Yoon, Seokhyun; Hong, Seonghwan; Kim, Hyun Jae

    2014-12-10

    We proposed a simple method to deposit a vertically graded oxygen-vacancy active layer (VGA) to enhance the positive bias stress (PBS) stability of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs). We deposited a-IGZO films by sputtering (target composition; In2O3:Ga2O3:ZnO = 1:1:1 mol %), and the oxygen partial pressure was varied during deposition so that the front channel of the TFTs was fabricated with low oxygen partial pressure and the back channel with high oxygen partial pressure. Using this method, we were able to control the oxygen vacancy concentration of the active layer so that it varied with depth. As a result, the turn-on voltage shift following a 10 000 s PBS of optimized VGA TFT was drastically improved from 12.0 to 5.6 V compared with a conventional a-IGZO TFT, without a significant decrease in the field effect mobility. These results came from the self-passivation effect and decrease in oxygen-vacancy-related trap sites of the VGA TFTs.

  17. Stacked organic photosensitive devices

    DOEpatents

    Forrest, Stephen; Xue, Jiangeng; Uchida, Soichi; Rand, Barry P.

    2007-03-27

    A device is provided having a first electrode, a second electrode, a first photoactive region having a characteristic absorption wavelength .lamda..sub.1 and a second photoactive region having a characteristic absorption wavelength .lamda..sub.2. The photoactive regions are disposed between the first and second electrodes, and further positioned on the same side of a reflective layer, such that the first photoactive region is closer to the reflective layer than the second photoactive region. The materials comprising the photoactive regions may be selected such that .lamda..sub.1 is at least about 10% different from .lamda..sub.2. The device may further comprise an exciton blocking layer disposed adjacent to and in direct contact with the organic acceptor material of each photoactive region, wherein the LUMO of each exciton blocking layer other than that closest to the cathode is not more than about 0.3 eV greater than the LUMO of the acceptor material.

  18. Bioelectronic Sensors and Devices

    NASA Astrophysics Data System (ADS)

    Reed, Mark

    Nanoscale electronic devices have recently enabled the ability to controllably probe biological systems, from the molecular to the cellular level, opening up new applications and understanding of biological function and response. This talk reviews some of the advances in the field, ranging from diagnostic and therapeutic applications, to cellular manipulation and response, to the emulation of biological response. In diagnostics, integrated nanodevice biosensors compatible with CMOS technology have achieved unprecedented sensitivity, enabling a wide range of label-free biochemical and macromolecule sensing applications down to femtomolar concentrations. These systems have demonstrated integrated assays of biomarkers at clinically important concentrations for both diagnostics and as a quantitative tool for drug design and discovery. Cellular level response can also be observed, including immune response function and dynamics. Finally, the field is beginning to create devices that emulate function, and the demonstration of a solid state artificial ion channel will be discussed.

  19. Light modulating device

    DOEpatents

    Rauh, R. David; Goldner, Ronald B.

    1989-01-01

    In a device for transmitting light, means for controlling the transmissivity of the device, including a ceramic, reversibly electrochromic, crystalline element having a highly reflective state when injected with electrons and charge compensating ions and a highly transmissive state when the electrons and ions are removed, the crystalline element being characterized as having a reflectivity of at least 50% in the reflective state and not greater than 10% in the transmissive state, and means for modulating the crystalline element between the reflective and transmissive states by injecting ions into the crystalline element in response to an applied electrical current of a first polarity and removing the ions in response to an applied electrical current of a second polarity.

  20. PRESSURE SENSING DEVICE

    DOEpatents

    Pope, K.E.

    1959-12-15

    This device is primarily useful as a switch which is selectively operable to actuate in response to either absolute or differential predetermined pressures. The device generally comprises a pressure-tight housing divided by a movable impermeable diaphragm into two chambers, a reference pressure chamber and a bulb chamber containing the switching means and otherwise filled with an incompressible non-conducting fluid. The switch means comprises a normally collapsed bulb having an electrically conductive outer surface and a vent tube leading to the housing exterior. The normally collapsed bulb is disposed such that upon its inflation, respensive to air inflow from the vent, two contacts fixed within the bulb chamber are adapted to be electrically shorted by the conducting outer surface of the bulb.

  1. Light modulating device

    DOEpatents

    Rauh, R.D.; Goldner, R.B.

    1989-12-26

    In a device for transmitting light, means for controlling the transmissivity of the device, including a ceramic, reversibly electrochromic, crystalline element having a highly reflective state when injected with electrons and charge compensating ions and a highly transmissive state when the electrons and ions are removed, the crystalline element being characterized as having a reflectivity of at least 50% in the reflective state and not greater than 10% in the transmissive state, and means for modulating the crystalline element between the reflective and transmissive states by injecting ions into the crystalline element in response to an applied electrical current of a first polarity and removing the ions in response to an applied electrical current of a second polarity are disclosed. 1 fig.

  2. GASEOUS DISCHARGE DEVICE

    DOEpatents

    Gow, J.D.

    1961-01-10

    An extremely compact two-terminal gaseous discharge device is described that is capable of producing neutrons in copious quantities, relatively high energy ions, intense x rays, and the like. Principal novelty resides in the provision of a crossed electric-magnetic field region in the discharge envelope that traps electrons and accelerates them to very high energies to provide an intense ionizing medium adjacent the anode of the device for ionizing gas therein with extremely high efficiency. In addition, the crossed-field trapping region holds the electrons close to the anode whereby the acceleration of ions to the cathode is not materially effected by the electron sheath and the ions assume substantially the full energy of the anodecathode potential drop. (auth)

  3. Microelectromechanical reprogrammable logic device

    PubMed Central

    Hafiz, M. A. A.; Kosuru, L.; Younis, M. I.

    2016-01-01

    In modern computing, the Boolean logic operations are set by interconnect schemes between the transistors. As the miniaturization in the component level to enhance the computational power is rapidly approaching physical limits, alternative computing methods are vigorously pursued. One of the desired aspects in the future computing approaches is the provision for hardware reconfigurability at run time to allow enhanced functionality. Here we demonstrate a reprogrammable logic device based on the electrothermal frequency modulation scheme of a single microelectromechanical resonator, capable of performing all the fundamental 2-bit logic functions as well as n-bit logic operations. Logic functions are performed by actively tuning the linear resonance frequency of the resonator operated at room temperature and under modest vacuum conditions, reprogrammable by the a.c.-driving frequency. The device is fabricated using complementary metal oxide semiconductor compatible mass fabrication process, suitable for on-chip integration, and promises an alternative electromechanical computing scheme. PMID:27021295

  4. Microelectromechanical reprogrammable logic device.

    PubMed

    Hafiz, M A A; Kosuru, L; Younis, M I

    2016-03-29

    In modern computing, the Boolean logic operations are set by interconnect schemes between the transistors. As the miniaturization in the component level to enhance the computational power is rapidly approaching physical limits, alternative computing methods are vigorously pursued. One of the desired aspects in the future computing approaches is the provision for hardware reconfigurability at run time to allow enhanced functionality. Here we demonstrate a reprogrammable logic device based on the electrothermal frequency modulation scheme of a single microelectromechanical resonator, capable of performing all the fundamental 2-bit logic functions as well as n-bit logic operations. Logic functions are performed by actively tuning the linear resonance frequency of the resonator operated at room temperature and under modest vacuum conditions, reprogrammable by the a.c.-driving frequency. The device is fabricated using complementary metal oxide semiconductor compatible mass fabrication process, suitable for on-chip integration, and promises an alternative electromechanical computing scheme.

  5. Bioanalysis in microfluidic devices.

    PubMed

    Khandurina, Julia; Guttman, András

    2002-01-18

    Microfabricated bioanalytical devices (also referred to as laboratory-on-a-chip or micro-TAS) offer highly efficient platforms for simultaneous analysis of a large number of biologically important molecules, possessing great potential for genome, proteome and metabolome studies. Development and implementation of microfluidic-based bioanalytical tools involves both established and evolving technologies, including microlithography, micromachining, micro-electromechanical systems technology and nanotechnology. This article provides an overview of the latest developments in the key device subject areas and the basic interdisciplinary technologies. Important aspects of DNA and protein analysis, interfacing issues and system integration are all thoroughly discussed, along with applications for this novel "synergized" technology in high-throughput separations of biologically important molecules. This review also gives a better understanding of how to utilize these technologies as well as to provide appropriate technical solutions to problems perceived as being more fundamental.

  6. Dielectrophoretic columnar focusing device

    SciTech Connect

    James, Conrad D; Galambos, Paul C; Derzon, Mark S

    2010-05-11

    A dielectrophoretic columnar focusing device uses interdigitated microelectrodes to provide a spatially non-uniform electric field in a fluid that generates a dipole within particles in the fluid. The electric field causes the particles to either be attracted to or repelled from regions where the electric field gradient is large, depending on whether the particles are more or less polarizable than the fluid. The particles can thereby be forced into well defined stable paths along the interdigitated microelectrodes. The device can be used for flow cytometry, particle control, and other process applications, including cell counting or other types of particle counting,more » and for separations in material control.« less

  7. Regenerative braking device

    DOEpatents

    Hoppie, Lyle O.

    1982-01-12

    Disclosed are several embodiments of a regenerative braking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.

  8. Deflectometry using portable devices

    NASA Astrophysics Data System (ADS)

    Butel, Guillaume P.; Smith, Greg A.; Burge, James H.

    2015-02-01

    Deflectometry is a powerful metrology technique that uses off-the-shelf equipment to achieve nanometer-level accuracy surface measurements. However, there is no portable device to quickly measure eyeglasses, lenses, or mirrors. We present an entirely portable new deflectometry technique that runs on any Android™ smartphone with a front-facing camera. Our technique overcomes some specific issues of portable devices like screen nonlinearity and automatic gain control. We demonstrate our application by measuring an amateur telescope mirror and simulating a measurement of the faulty Hubble Space Telescope primary mirror. Our technique can, in less than 1 min, measure surface errors with accuracy up to 50 nm RMS, simply using a smartphone.

  9. Dielectrokinetic chromatography devices

    DOEpatents

    Chirica, Gabriela S; Fiechtner, Gregory J; Singh, Anup K

    2014-12-16

    Disclosed herein are methods and devices for dielectrokinetic chromatography. As disclosed, the devices comprise microchannels having at least one perturber which produces a non-uniformity in a field spanning the width of the microchannel. The interaction of the field non-uniformity with a perturber produces a secondary flow which competes with a primary flow. By decreasing the size of the perturber the secondary flow becomes significant for particles/analytes in the nanometer-size range. Depending on the nature of a particle/analyte present in the fluid and its interaction with the primary flow and the secondary flow, the analyte may be retained or redirected. The composition of the primary flow can be varied to affect the magnitude of primary and/or secondary flows on the particles/analytes and thereby separate and concentrate it from other particles/analytes.

  10. Portable biochip scanner device

    DOEpatents

    Perov, Alexander; Sharonov, Alexei; Mirzabekov, Andrei D.

    2002-01-01

    A portable biochip scanner device used to detect and acquire fluorescence signal data from biological microchips (biochips) is provided. The portable biochip scanner device employs a laser for emitting an excitation beam. An optical fiber delivers the laser beam to a portable biochip scanner. A lens collimates the laser beam, the collimated laser beam is deflected by a dichroic mirror and focused by an objective lens onto a biochip. The fluorescence light from the biochip is collected and collimated by the objective lens. The fluorescence light is delivered to a photomultiplier tube (PMT) via an emission filter and a focusing lens. The focusing lens focuses the fluorescence light into a pinhole. A signal output of the PMT is processed and displayed.

  11. Elastomeric load sharing device

    NASA Technical Reports Server (NTRS)

    Isabelle, Charles J. (Inventor); Kish, Jules G. (Inventor); Stone, Robert A. (Inventor)

    1992-01-01

    An elastomeric load sharing device, interposed in combination between a driven gear and a central drive shaft to facilitate balanced torque distribution in split power transmission systems, includes a cylindrical elastomeric bearing and a plurality of elastomeric bearing pads. The elastomeric bearing and bearing pads comprise one or more layers, each layer including an elastomer having a metal backing strip secured thereto. The elastomeric bearing is configured to have a high radial stiffness and a low torsional stiffness and is operative to radially center the driven gear and to minimize torque transfer through the elastomeric bearing. The bearing pads are configured to have a low radial and torsional stiffness and a high axial stiffness and are operative to compressively transmit torque from the driven gear to the drive shaft. The elastomeric load sharing device has spring rates that compensate for mechanical deviations in the gear train assembly to provide balanced torque distribution between complementary load paths of split power transmission systems.

  12. Micro-Organ Devices

    NASA Technical Reports Server (NTRS)

    Gonda, Steven R.; Leslie, Julia; Chang, Robert C.; Starly, Binil; Sun, Wei; Culbertson, Christopher; Holtorf, Heidi

    2009-01-01

    Micro-organ devices (MODs) are being developed to satisfy an emerging need for small, lightweight, reproducible, biological-experimentati on apparatuses that are amenable to automated operation and that imp ose minimal demands for resources (principally, power and fluids). I n simplest terms, a MOD is a microfluidic device containing a variety of microstructures and assemblies of cells, all designed to mimic a complex in vivo microenvironment by replicating one or more in vivo micro-organ structures, the architectures and composition of the extr acellular matrices in the organs of interest, and the in vivo fluid flows. In addition to microscopic flow channels, a MOD contains one or more micro-organ wells containing cells residing in microscopic e xtracellular matrices and/or scaffolds, the shapes and compositions o f which enable replication of the corresponding in vivo cell assembl ies and flows.

  13. Cable shield connecting device

    DOEpatents

    Silva, Frank A.

    1979-01-01

    A cable shield connecting device for installation on a high voltage cable of the type having a metallic shield, the device including a relatively conformable, looped metal bar for placement around a bared portion of the metallic shield to extend circumferentially around a major portion of the circumference of the metallic shield while being spaced radially therefrom, a plurality of relatively flexible metallic fingers affixed to the bar, projecting from the bar in an axial direction and spaced circumferentially along the bar, each finger being attached to the metallic shield at a portion located remote from the bar to make electrical contact with the metallic shield, and a connecting conductor integral with the bar.

  14. Inertial energy storage device

    DOEpatents

    Knight, Jr., Charles E.; Kelly, James J.; Pollard, Roy E.

    1978-01-01

    The inertial energy storage device of the present invention comprises a composite ring formed of circumferentially wound resin-impregnated filament material, a flanged hollow metal hub concentrically disposed in the ring, and a plurality of discrete filament bandsets coupling the hub to the ring. Each bandset is formed of a pair of parallel bands affixed to the hub in a spaced apart relationship with the axis of rotation of the hub being disposed between the bands and with each band being in the configuration of a hoop extending about the ring along a chordal plane thereof. The bandsets are disposed in an angular relationship with one another so as to encircle the ring at spaced-apart circumferential locations while being disposed in an overlapping relationship on the flanges of the hub. The energy storage device of the present invention has the capability of substantial energy storage due to the relationship of the filament bands to the ring and the flanged hub.

  15. Support and maneuvering device

    DOEpatents

    Wood, Richard L.

    1988-01-01

    A support and maneuvering device includes an elongated flexible inflatable enclosure having a fixed end and a movable end. The movable end is collapsible toward the fixed end to a contracted position when the enclosure is in a noninflated condition. Upon inflation, the movable end is movable away from the fixed end to an extended position. The movable end includes means for mounting an article such as a solar reflector thereon. The device also includes a plurality of position controlling means disposed about the movable end to effect adjusting movement of portions thereof by predetermined amounts and for controlling an angle at which the article disposed at the movable end is oriented. The plurality of position controlling means limits a suitable number degrees of freedom of the movable end for transmitting a steering motion thereto and for controlling the position thereof.

  16. Particle capture device

    DOEpatents

    Jayne, John T.; Worsnop, Douglas R.

    2016-02-23

    In example embodiments, particle collection efficiency in aerosol analyzers and other particle measuring instruments is improved by a particle capture device that employs multiple collisions to decrease momentum of particles until the particles are collected (e.g., vaporized or come to rest). The particle collection device includes an aperture through which a focused particle beam enters. A collection enclosure is coupled to the aperture and has one or more internal surfaces against which particles of the focused beam collide. One or more features are employed in the collection enclosure to promote particles to collide multiple times within the enclosure, and thereby be vaporized or come to rest, rather than escape through the aperture.

  17. Anti-gravity device

    NASA Technical Reports Server (NTRS)

    Palsingh, S. (Inventor)

    1975-01-01

    An educational toy useful in demonstrating fundamental concepts regarding the laws of gravity is described. The device comprises a sphere 10 of radius r resting on top of sphere 12 of radius R. The center of gravity of sphere 10 is displaced from its geometrical center by distance D. The dimensions are so related that D((R+r)/r) is greater than r. With the center of gravity of sphere 10 lying on a vertical line, the device is in equilibrium. When sphere 10 is rolled on the surface of sphere 12 it will return to its equilibrium position upon release. This creates an illusion that sphere 10 is defying the laws of gravity. In reality, due to the above noted relationship of D, R, and r, the center of gravity of sphere 10 rises from its equilibrium position as it rolls a short distance up or down the surface of sphere 12.

  18. Microelectromechanical safe arm device

    DOEpatents

    Roesler, Alexander W [Tijeras, NM

    2012-06-05

    Microelectromechanical (MEM) apparatus and methods for operating, for preventing unintentional detonation of energetic components comprising pyrotechnic and explosive materials, such as air bag deployment systems, munitions and pyrotechnics. The MEM apparatus comprises an interrupting member that can be moved to block (interrupt) or complete (uninterrupt) an explosive train that is part of an energetic component. One or more latching members are provided that engage and prevent the movement of the interrupting member, until the one or more latching members are disengaged from the interrupting member. The MEM apparatus can be utilized as a safe and arm device (SAD) and electronic safe and arm device (ESAD) in preventing unintentional detonations. Methods for operating the MEM apparatus include independently applying drive signals to the actuators coupled to the latching members, and an actuator coupled to the interrupting member.

  19. Tire deflation device

    DOEpatents

    Barker, Stacey G [Idaho Falls, ID

    2010-01-05

    A tire deflation device includes (1) a component having a plurality of bores, (2) a plurality of spikes removably insertable into the plurality of bores and (3) a keeper within each among the plurality of bores, the keeper being configured to contact a sidewall surface of a spike among the plurality of spikes and to exert force upon the sidewall surface. In an embodiment, the tire deflation device includes (a) a component including a bore in a material, the bore including a receiving region, a sidewall surface and a base surface, (b) a channel extending from the sidewall surface into the material, (c) a keeper having a first section housed within the channel and a second section which extends past the sidewall surface into the receiving region, and (d) a spike removably insertable into the bore.

  20. Support and maneuvering device

    DOEpatents

    Wood, R.L.

    1987-03-23

    A support and maneuvering device includes an elongated flexible inflatable enclosure having a fixed end and a movable end. The movable end is collapsible toward the fixed end to a contracted position when the enclosure is in a noninflated condition. Upon inflation, the movable end is movable away from the fixed end to an extended position. The movable end includes means for mounting an article such as a solar reflector thereon. The device also includes a plurality of position controlling means disposed about the movable end to effect adjusting movement of portions thereof by predetermined amounts and for controlling an angle at which the article disposed at the movable end is oriented. The plurality of position controlling means limits a suitable number degrees of freedom of the movable end for transmitting a steering motion thereto and for controlling the position thereof. 9 figs.

  1. Organic photosensitive devices

    DOEpatents

    Peumans, Peter; Forrest, Stephen R.

    2013-01-22

    A photoactive device is provided. The device includes a first electrode, a second electrode, and a photoactive region disposed between and electrically connected to the first and second electrodes. The photoactive region further includes an organic donor layer and an organic acceptor layer that form a donor-acceptor heterojunction. The mobility of holes in the organic donor region and the mobility of electrons in the organic acceptor region are different by a factor of at least 100, and more preferably a factor of at least 1000. At least one of the mobility of holes in the organic donor region and the mobility of electrons in the organic acceptor region is greater than 0.001 cm.sup.2/V-sec, and more preferably greater than 1 cm.sup.2/V-sec. The heterojunction may be of various types, including a planar heterojunction, a bulk heterojunction, a mixed heterojunction, and a hybrid planar-mixed heterojunction.

  2. GAS DISCHARGE DEVICES

    DOEpatents

    Jefferson, S.

    1958-11-11

    An apparatus utilized in introducing tritium gas into envelope of a gas discharge device for the purpose f maintaining the discharge path in ionized condition is described. ln addition to the cathode and anode, the ischarge device contains a zirconium or tantalum ilament arranged for external excitation and a metallic seed containing tritium, and also arranged to have a current passed through it. Initially, the zirconium or tantalum filament is vaporized to deposit its material adjacent the main discharge region. Then the tritium gas is released and, due to its affinity for the first released material, it deposits in the region of the main discharge where it is most effective in maintaining the discharge path in an ionized condition.

  3. Urine collection device

    NASA Technical Reports Server (NTRS)

    Michaud, R. B. (Inventor)

    1981-01-01

    A urine collection device for females is described. It is comprised of a collection element defining a urine collection chamber and an inlet opening into the chamber and is adapted to be disposed in surrounding relation to the urethral opening of the user. A drainage conduit is connected to the collection element in communication with the chamber whereby the chamber and conduit together comprise a urine flow pathway for carrying urine generally away from the inlet. A first body of wicking material is mounted adjacent the collection element and extends at least partially into the flow pathway. The device preferably also comprise a vaginal insert element including a seal portion for preventing the entry of urine into the vagina.

  4. Nuclear reactor safety device

    DOEpatents

    Hutter, Ernest

    1986-01-01

    A safety device is disclosed for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of an upward thermal excursion. Such safety device comprises a laminated helical ribbon configured as a tube-like helical coil having contiguous helical turns with slidably abutting edges. The helical coil is disclosed as a portion of a drive member connected axially to the control rod. The laminated ribbon is formed of outer and inner laminae. The material of the outer lamina has a greater thermal coefficient of expansion than the material of the inner lamina. In the event of an upward thermal excursion, the laminated helical coil curls inwardly to a smaller diameter. Such inward curling causes the total length of the helical coil to increase by a substantial increment, so that the control rod is axially repositioned by a corresponding amount to reduce the power output of the reactor.

  5. Fabrication of high-performance InGaZnOx thin film transistors based on control of oxidation using a low-temperature plasma

    NASA Astrophysics Data System (ADS)

    Takenaka, Kosuke; Endo, Masashi; Uchida, Giichiro; Setsuhara, Yuichi

    2018-04-01

    This work demonstrated the low-temperature control of the oxidation of Amorphous InGaZnOx (a-IGZO) films using inductively coupled plasma as a means of precisely tuning the properties of thin film transistors (TFTs) and as an alternative to post-deposition annealing at high temperatures. The effects of the plasma treatment of the as-deposited a-IGZO films were investigated by assessing the electrical properties of TFTs incorporating these films. A TFT fabricated using an a-IGZO film exposed to an Ar-H2-O2 plasma at substrate temperatures as low as 300 °C exhibited the best performance, with a field effect mobility as high as 42.2 cm2 V-1 s-1, a subthreshold gate voltage swing of 1.2 V decade-1, and a threshold voltage of 2.8 V. The improved transfer characteristics of TFTs fabricated with a-IGZO thin films treated using an Ar-H2-O2 plasma are attributed to the termination of oxygen vacancies around Ga and Zn atoms by OH radicals in the gas phase.

  6. Periodically pulsed wet annealing approach for low-temperature processable amorphous InGaZnO thin film transistors with high electrical performance and ultrathin thickness

    PubMed Central

    Kim, Ye Kyun; Ahn, Cheol Hyoun; Yun, Myeong Gu; Cho, Sung Woon; Kang, Won Jun; Cho, Hyung Koun

    2016-01-01

    In this paper, a simple and controllable “wet pulse annealing” technique for the fabrication of flexible amorphous InGaZnO thin film transistors (a-IGZO TFTs) processed at low temperature (150 °C) by using scalable vacuum deposition is proposed. This method entailed the quick injection of water vapor for 0.1 s and purge treatment in dry ambient in one cycle; the supply content of water vapor was simply controlled by the number of pulse repetitions. The electrical transport characteristics revealed a remarkable performance of the a-IGZO TFTs prepared at the maximum process temperature of 150 °C (field-effect mobility of 13.3 cm2 V−1 s−1; Ion/Ioff ratio ≈ 108; reduced I-V hysteresis), comparable to that of a-IGZO TFTs annealed at 350 °C in dry ambient. Upon analysis of the angle-resolved x-ray photoelectron spectroscopy, the good performance was attributed to the effective suppression of the formation of hydroxide and oxygen-related defects. Finally, by using the wet pulse annealing process, we fabricated, on a plastic substrate, an ultrathin flexible a-IGZO TFT with good electrical and bending performances. PMID:27198067

  7. Periodically pulsed wet annealing approach for low-temperature processable amorphous InGaZnO thin film transistors with high electrical performance and ultrathin thickness.

    PubMed

    Kim, Ye Kyun; Ahn, Cheol Hyoun; Yun, Myeong Gu; Cho, Sung Woon; Kang, Won Jun; Cho, Hyung Koun

    2016-05-20

    In this paper, a simple and controllable "wet pulse annealing" technique for the fabrication of flexible amorphous InGaZnO thin film transistors (a-IGZO TFTs) processed at low temperature (150 °C) by using scalable vacuum deposition is proposed. This method entailed the quick injection of water vapor for 0.1 s and purge treatment in dry ambient in one cycle; the supply content of water vapor was simply controlled by the number of pulse repetitions. The electrical transport characteristics revealed a remarkable performance of the a-IGZO TFTs prepared at the maximum process temperature of 150 °C (field-effect mobility of 13.3 cm(2) V(-1) s(-1); Ion/Ioff ratio ≈ 10(8); reduced I-V hysteresis), comparable to that of a-IGZO TFTs annealed at 350 °C in dry ambient. Upon analysis of the angle-resolved x-ray photoelectron spectroscopy, the good performance was attributed to the effective suppression of the formation of hydroxide and oxygen-related defects. Finally, by using the wet pulse annealing process, we fabricated, on a plastic substrate, an ultrathin flexible a-IGZO TFT with good electrical and bending performances.

  8. Microneedle Device Prototype

    DTIC Science & Technology

    2014-05-01

    Defense Threat Reduction Agency Research and Development Counter WMD Technologies Test Support Division 1680 Texas Street SE Kirtland AFB, NM...Device Prototype Final Report iv | List of Figures List of Figures Figure 3-1. Print screen of the STL file of a hollow microneedle design in Alibre...electrochemical characterization of gold electrode (n = 8) array with oxide dielectric defined working electrodes with 1 mM [Fe(CN)6] 3- in 0.1 M potassium

  9. Temperature measuring device

    SciTech Connect

    Lauf, R.J.; Bible, D.W.; Sohns, C.W.

    1999-10-19

    Systems and methods are described for a wireless instrumented silicon wafer that can measure temperatures at various points and transmit those temperature readings to an external receiver. The device has particular utility in the processing of semiconductor wafers, where it can be used to map thermal uniformity on hot plates, cold plates, spin bowl chucks, etc. without the inconvenience of wires or the inevitable thermal perturbations attendant with them.

  10. Temperature measuring device

    DOEpatents

    Lauf, Robert J.; Bible, Don W.; Sohns, Carl W.

    1999-01-01

    Systems and methods are described for a wireless instrumented silicon wafer that can measure temperatures at various points and transmit those temperature readings to an external receiver. The device has particular utility in the processing of semiconductor wafers, where it can be used to map thermal uniformity on hot plates, cold plates, spin bowl chucks, etc. without the inconvenience of wires or the inevitable thermal perturbations attendant with them.

  11. Fiber optic monitoring device

    DOEpatents

    Samborsky, James K.

    1993-01-01

    A device for the purpose of monitoring light transmissions in optical fibers comprises a fiber optic tap that optically diverts a fraction of a transmitted optical signal without disrupting the integrity of the signal. The diverted signal is carried, preferably by the fiber optic tap, to a lens or lens system that disperses the light over a solid angle that facilitates viewing. The dispersed light indicates whether or not the monitored optical fiber or system of optical fibers is currently transmitting optical information.

  12. Alignment reference device

    DOEpatents

    Patton, Gail Y.; Torgerson, Darrel D.

    1987-01-01

    An alignment reference device provides a collimated laser beam that minimizes angular deviations therein. A laser beam source outputs the beam into a single mode optical fiber. The output end of the optical fiber acts as a source of radiant energy and is positioned at the focal point of a lens system where the focal point is positioned within the lens. The output beam reflects off a mirror back to the lens that produces a collimated beam.

  13. Thermal Remote Anemometer Device

    NASA Technical Reports Server (NTRS)

    Heyman, Joseph S.; Heath, D. Michele; Winfree, William P.; Miller, William E.; Welch, Christopher S.

    1988-01-01

    Thermal Remote Anemometer Device developed for remote, noncontacting, passive measurement of thermal properties of sample. Model heated locally by scanning laser beam and cooled by wind in tunnel. Thermal image of model analyzed to deduce pattern of airflow around model. For materials applications, system used for evaluation of thin films and determination of thermal diffusivity and adhesive-layer contact. For medical applications, measures perfusion through skin to characterize blood flow and used to determine viabilities of grafts and to characterize tissues.

  14. Millimeter Wave Nonreciprocal Devices.

    DTIC Science & Technology

    1983-01-03

    measures microwave magnetic field patterns of magnetostatic waves in LPE -YIG thin films has been developed. The probe’s sensing element is either a...Morgenthaler, "Workshop on Application of Garnet and Ferrite Thin Films to Microwave Devices," Session FC, Third Joint Intermag - Magnetism and...thin films Li... millimeter waves magnetostati c waves i A TRAC" =CmE4 F*91040 eEp y mnenu -d Dfenvely by Noek n.m--) The Microwave and Quantum

  15. Biomolecular detection device

    DOEpatents

    Huo, Qisheng [Albuquerque, NM; Liu, Jun [Albuquerque, NM

    2008-10-21

    A device for detecting and measuring the concentration of biomolecules in solution, utilizing a conducting electrode in contact with a solution containing target biomolecules, with a film with controllable pore size distribution characteristics applied to at least one surface of the conducting electrode. The film is functionalized with probe molecules that chemically interact with the target biomolecules at the film surface, blocking indicator molecules present in solution from diffusing from the solution to the electrode, thereby changing the electrochemical response of the electrode.

  16. Functional Epitaxial Oxide Devices

    DTIC Science & Technology

    2010-04-12

    complex oxides , epitaxial growth, antennas, varactors 16. SECURITY CLASSIFICATION OF: REPORT U b. ABSTRACT u c. THIS PAGE u 17. LIMITATION OF...Technical Report DATES COVERED (From - To) 17-06-2008-31-12-2009 4. TITLE AND SUBTITLE Functional Epitaxial Oxide Devices 5a. CONTRACT NUMBER NA...This research effort addresses the need for high performance radio frequency (RF) components, specifically varactors and miniaturized, high gain

  17. Residual gas analysis device

    DOEpatents

    Thornberg, Steven M [Peralta, NM

    2012-07-31

    A system is provided for testing the hermeticity of a package, such as a microelectromechanical systems package containing a sealed gas volume, with a sampling device that has the capability to isolate the package and breach the gas seal connected to a pulse valve that can controllably transmit small volumes down to 2 nanoliters to a gas chamber for analysis using gas chromatography/mass spectroscopy diagnostics.

  18. Hybrid electroluminescent devices

    DOEpatents

    Shiang, Joseph John; Duggal, Anil Raj; Michael, Joseph Darryl

    2010-08-03

    A hybrid electroluminescent (EL) device comprises at least one inorganic diode element and at least one organic EL element that are electrically connected in series. The absolute value of the breakdown voltage of the inorganic diode element is greater than the absolute value of the maximum reverse bias voltage across the series. The inorganic diode element can be a power diode, a Schottky barrier diode, or a light-emitting diode.

  19. Mechanical devices: A compilation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A collection of new technology items that should be of interest to mechanical engineers, machinists, and others who design or work with mechanical devices was described. Section 1 contains articles on several new or modified tools, Section 2 describes a number of specialized mechanical systems, and the last section is devoted to valves, bearings, and other parts that might be used with larger systems. The last patent information available is also given.

  20. Relativistic electron beam device

    DOEpatents

    Freeman, J.R.; Poukey, J.W.; Shope, S.L.; Yonas, G.

    1975-07-01

    A design is given for an electron beam device for irradiating spherical hydrogen isotope bearing targets. The accelerator, which includes hollow cathodes facing each other, injects an anode plasma between the cathodes and produces an approximately 10 nanosecond, megajoule pulse between the anode plasma and the cathodes. Targets may be repetitively positioned within the plasma between the cathodes, and accelerator diode arrangement permits materials to survive operation in a fusion power source. (auth)

  1. Liquid level sensing device

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    A liquid level sensing device comprising a load cell supporting a column or stack of segments freely resting on one another. The density of each element is substantially identical to that of the surrounding liquid. The elements are freely guided within a surrounding tube. As each element is exposed above the liquid level, its weight will be impressed through the column to the load cell, thereby providing a signal at the load cell directly proportional to the liquid level elevation.

  2. Sectional device handling tool

    DOEpatents

    Candee, Clark B.

    1988-07-12

    Apparatus for remotely handling a device in an irradiated underwater environment includes a plurality of tubular sections interconnected end-to-end to form a handling structure, the bottom section being adapted for connection to the device. A support section is connected to the top tubular section and is adapted to be suspended from an overhead crane. Each section is flanged at its opposite ends. Axially retractable bolts in each bottom flange are threadedly engageable with holes in the top flange of an adjacent section, each bolt being biased to its retracted position and retained in place on the bottom flange. Guide pins on each top flange cooperate with mating holes on adjacent bottom flanges to guide movement of the parts to the proper interconnection orientation. Each section carries two hydraulic line segments provided with quick-connect/disconnect fittings at their opposite ends for connection to the segments of adjacent tubular sections upon interconnection thereof to form control lines which are connectable to the device and to an associated control console.

  3. Plasma jet ignition device

    DOEpatents

    McIlwain, Michael E.; Grant, Jonathan F.; Golenko, Zsolt; Wittstein, Alan D.

    1985-01-15

    An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity insert containing a plurality of spaced, metal rings. The rings act as secondary spark gap electrodes reducing the voltage needed to maintain the initial arc in the cavity.

  4. Non- contacting capacitive diagnostic device

    DOEpatents

    Ellison, Timothy

    2005-07-12

    A non-contacting capacitive diagnostic device includes a pulsed light source for producing an electric field in a semiconductor or photovoltaic device or material to be evaluated and a circuit responsive to the electric field. The circuit is not in physical contact with the device or material being evaluated and produces an electrical signal characteristic of the electric field produced in the device or material. The diagnostic device permits quality control and evaluation of semiconductor or photovoltaic device properties in continuous manufacturing processes.

  5. Packaging of solid state devices

    DOEpatents

    Glidden, Steven C.; Sanders, Howard D.

    2006-01-03

    A package for one or more solid state devices in a single module that allows for operation at high voltage, high current, or both high voltage and high current. Low thermal resistance between the solid state devices and an exterior of the package and matched coefficient of thermal expansion between the solid state devices and the materials used in packaging enables high power operation. The solid state devices are soldered between two layers of ceramic with metal traces that interconnect the devices and external contacts. This approach provides a simple method for assembling and encapsulating high power solid state devices.

  6. Interfacial Chemistry-Induced Modulation of Schottky Barrier Heights: In Situ Measurements of the Pt-Amorphous Indium Gallium Zinc Oxide Interface Using X-ray Photoelectron Spectroscopy

    SciTech Connect

    Flynn, Brendan T.; Oleksak, Richard P.; Thevuthasan, Suntharampillai

    A method to modulate the Schottky barrier heights for platinum and amorphous indium gallium zinc oxide (a-IGZO) interfaces is demonstrated through thermal processing and background ambient pressure control. The interfacial chemistries that modulate barrier heights for the Pt/a-IGZO system were investigated using in-situ X-ray photoelectron spectroscopy. A significant reduction of indium, from In3+ to In0, occurs during deposition of Pt on to the a-IGZO surface in ultra-high vacuum. Post-annealing and controlling the background ambient O2 pressure allows tuning the degree of indium reduction and the corresponding Schottky barrier height between 0.17 to 0.77 eV. Understanding the detailed interfacial chemistries atmore » Pt/a-IGZO interfaces may allow for improved electronic device performance, including Schottky diodes, memristors, and metalsemiconductor field-effect transistors.« less

  7. Interfacial Chemistry-Induced Modulation of Schottky Barrier Heights: In Situ Measurements of the Pt–Amorphous Indium Gallium Zinc Oxide Interface Using X-ray Photoelectron Spectroscopy

    SciTech Connect

    Flynn, Brendan T.; Oleksak, Richard P.; Thevuthasan, Suntharampillai

    A method to modulate the Schottky barrier heights for platinum and amorphous indium gallium zinc oxide (a-IGZO) interfaces is demonstrated through thermal processing and background ambient pressure control. The interfacial chemistries that modulate barrier heights for the Pt/a-IGZO system were investigated using in-situ X-ray photoelectron spectroscopy. A significant reduction of indium, from In 3+ to In 0, occurs during deposition of Pt on to the a-IGZO surface in ultra-high vacuum. Post-annealing and controlling the background ambient O 2 pressure allows tuning the degree of indium reduction and the corresponding Schottky barrier height between 0.17 to 0.77 eV. Understanding the detailedmore » interfacial chemistries at Pt/a-IGZO interfaces may allow for improved electronic device performance, including Schottky diodes, memristors, and metalsemiconductor field-effect transistors.« less

  8. Photoemission-based microelectronic devices

    PubMed Central

    Forati, Ebrahim; Dill, Tyler J.; Tao, Andrea R.; Sievenpiper, Dan

    2016-01-01

    The vast majority of modern microelectronic devices rely on carriers within semiconductors due to their integrability. Therefore, the performance of these devices is limited due to natural semiconductor properties such as band gap and electron velocity. Replacing the semiconductor channel in conventional microelectronic devices with a gas or vacuum channel may scale their speed, wavelength and power beyond what is available today. However, liberating electrons into gas/vacuum in a practical microelectronic device is quite challenging. It often requires heating, applying high voltages, or using lasers with short wavelengths or high powers. Here, we show that the interaction between an engineered resonant surface and a low-power infrared laser can cause enough photoemission via electron tunnelling to implement feasible microelectronic devices such as transistors, switches and modulators. The proposed photoemission-based devices benefit from the advantages of gas-plasma/vacuum electronic devices while preserving the integrability of semiconductor-based devices. PMID:27811946

  9. Nonimaging radiant energy direction device

    DOEpatents

    Winston, Roland

    1980-01-01

    A raidant energy nonimaging light direction device is provided. The device includes an energy transducer and a reflective wall whose contour is particularly determined with respect to the geometrical vector flux of a field associated with the transducer.

  10. Case outsourcing medical device reprocessing.

    PubMed

    Haley, Deborah

    2004-04-01

    IN THE INTEREST OF SAVING MONEY, many hospitals are considering extending the life of some single-use medical devices by using medical device reprocessing programs. FACILITIES OFTEN LACK the resources required to meet the US Food and Drug Administration's tough quality assurance standards. BY OUTSOURCING, hospitals can reap the benefits of medical device reprocessing without assuming additional staffing and compliance burdens. OUTSOURCING enables hospitals to implement a medical device reprocessing program quickly, with no capital investment and minimal effort.

  11. Impact of repeated uniaxial mechanical strain on flexible a-IGZO thin film transistors with symmetric and asymmetric structures

    NASA Astrophysics Data System (ADS)

    Liao, Po-Yung; Chang, Ting-Chang; Su, Wan-Ching; Chen, Bo-Wei; Chen, Li-Hui; Hsieh, Tien-Yu; Yang, Chung-Yi; Chang, Kuan-Chang; Zhang, Sheng-Dong; Huang, Yen-Yu; Chang, Hsi-Ming; Chiang, Shin-Chuan

    2017-06-01

    This letter investigates repeated uniaxial mechanical stress-induced degradation behavior in flexible amorphous In-Ga-Zn-O thin-film transistors (TFTs) of different geometric structures. Two types of via-contact structure TFTs are investigated: symmetrical and UI structure (TFTs with I- and U-shaped asymmetric electrodes). After repeated mechanical stress, I-V curves for the symmetrical structure show a significant negative threshold voltage (VT) shift, due to mechanical stress-induced oxygen vacancy generation. However, degradation in the UI structure TFTs after stress is a negative VT shift along with the parasitic transistor characteristic in the forward-operation mode, with this hump not evident in the reverse-operation mode. This asymmetrical degradation is clarified by the mechanical strain simulation of the UI TFTs.

  12. Abnormal hump in capacitance-voltage measurements induced by ultraviolet light in a-IGZO thin-film transistors

    NASA Astrophysics Data System (ADS)

    Tsao, Yu-Ching; Chang, Ting-Chang; Chen, Hua-Mao; Chen, Bo-Wei; Chiang, Hsiao-Cheng; Chen, Guan-Fu; Chien, Yu-Chieh; Tai, Ya-Hsiang; Hung, Yu-Ju; Huang, Shin-Ping; Yang, Chung-Yi; Chou, Wu-Ching

    2017-01-01

    This work demonstrates the generation of abnormal capacitance for amorphous indium-gallium-zinc oxide (a-InGaZnO4) thin-film transistors after being subjected to negative bias stress under ultraviolet light illumination stress (NBIS). At various operation frequencies, there are two-step tendencies in their capacitance-voltage curves. When gate bias is smaller than threshold voltage, the measured capacitance is dominated by interface defects. Conversely, the measured capacitance is dominated by oxygen vacancies when gate bias is larger than threshold voltage. The impact of these interface defects and oxygen vacancies on capacitance-voltage curves is verified by TCAD simulation software.

  13. 77 FR 58576 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-21

    ... Devices, Portable Music and Data Processing Devices, Computers, and Components Thereof; Institution of... communication devices, portable music and data processing devices, computers, and components thereof by reason... certain wireless communication devices, portable music and data processing devices, computers, and...

  14. 78 FR 34669 - Certain Electronic Devices, Including Wireless Communication Devices, Portable Music and Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-10

    ..., Including Wireless Communication Devices, Portable Music and Data Processing Devices, and Tablet Computers... importing wireless communication devices, portable music and data processing devices, and tablet computers... certain electronic devices, including wireless communication devices, portable music and data processing...

  15. Portable source identification device

    NASA Astrophysics Data System (ADS)

    Andersen, Eric S.; Samuel, Todd J.; Gervais, Kevin L.

    2005-05-01

    U.S. Customs and Border Protection (CBP) is the primary enforcement agency protecting the nation"s ports of entry. CBP is enhancing its capability to interdict the illicit import of nuclear and radiological materials and devices that may be used by terrorists. Pacific Northwest National Laboratory (PNNL) is providing scientific and technical support to CBP in their goal to enable rapid deployment of nuclear and radiation detection systems at U. S. ports of entry to monitor 100% of the incoming international traffic and cargo while not adversely impacting the operations or throughput of the ports. As the deployment of radiation detection systems proceeds, there is a need to adapt the baseline radiation portal monitor (RPM) system technology to operations at these diverse ports of entry. When screening produces an alarm in the primary inspection RPM, the alarming vehicle is removed from the flow of commerce and the alarm is typically confirmed in a secondary inspection RPM. The portable source identification device (PSID) is a radiation sensor panel (RSP), based on thallium-doped sodium iodide (NaI(Tl)) scintillation detector and gamma spectroscopic analysis hardware and software, mounted on a scissor lift on a small truck. The lift supports a box containing a commercial off-the-shelf (COTS) sodium iodide detector that provides real-time isotopic identification, including neutron detectors to interdict Weapons of Mass Destruction (WMD) and radiation dispersion devices (RDD). The scissor lift will lower the detectors to within a foot off the ground and raise them to approximately 24 feet (7.3 m) in the air, allowing a wide vertical scanning range.

  16. Nanotube resonator devices

    DOEpatents

    Jensen, Kenneth J; Zettl, Alexander K; Weldon, Jeffrey A

    2014-05-06

    A fully-functional radio receiver fabricated from a single nanotube is being disclosed. Simultaneously, a single nanotube can perform the functions of all major components of a radio: antenna, tunable band-pass filter, amplifier, and demodulator. A DC voltage source, as supplied by a battery, can power the radio. Using carrier waves in the commercially relevant 40-400 MHz range and both frequency and amplitude modulation techniques, successful music and voice reception has been demonstrated. Also disclosed are a radio transmitter and a mass sensor using a nanotube resonator device.

  17. Resistive Exercise Device

    NASA Technical Reports Server (NTRS)

    Smith, Damon C. (Inventor)

    2005-01-01

    An exercise device 10 is particularly well suited for use in low gravity environments, and includes a frame 12 with plurality of resistance elements 30,82 supported in parallel on the frame. A load transfer member 20 is moveable relative to the frame for transferring the applied force to the free end of each captured resistance element. Load selection template 14 is removably secured both to the load transfer member, and a plurality of capture mechanisms engage the free end of corresponding resistance elements. The force applying mechanism 53 may be a handle, harness or other user interface for applying a force to move the load transfer member.

  18. Portable hand hold device

    NASA Technical Reports Server (NTRS)

    Redmon, Jr., John W. (Inventor); McQueen, Donald H. (Inventor); Sanders, Fred G. (Inventor)

    1990-01-01

    A hand hold device (A) includes a housing (10) having a hand hold (14) and clamping brackets (32,34) for grasping and handling an object. A drive includes drive lever (23), spur gear (22), and rack gears (24,26) carried on rods (24a, 26a) for moving the clamping brackets. A lock includes ratchet gear (40) and pawl (42) biased between lock and unlock positions by a cantilever spring (46,48) and moved by handle (54). Compliant grip pads (32b, 34b) provide compliance to lock, unlock, and hold an object between the clamp brackets.

  19. Detached rock evaluation device

    DOEpatents

    Hanson, David R.

    1986-01-01

    A rock detachment evaluation device (10) having an energy transducer unit 1) for sensing vibrations imparted to a subject rock (172) for converting the sensed vibrations into electrical signals, a low band pass filter unit (12) for receiving the electrical signal and transmitting only a low frequency segment thereof, a high band pass filter unit (13) for receiving the electrical signals and for transmitting only a high frequency segment thereof, a comparison unit (14) for receiving the low frequency and high frequency signals and for determining the difference in power between the signals, and a display unit (16) for displaying indicia of the difference, which provides a quantitative measure of rock detachment.

  20. Micro environmental sensing device

    DOEpatents

    Polosky, Marc A.; Lukens, Laurance L.

    2006-05-02

    A microelectromechanical (MEM) acceleration switch is disclosed which includes a proof mass flexibly connected to a substrate, with the proof mass being moveable in a direction substantially perpendicular to the substrate in response to a sensed acceleration. An electrode on the proof mass contacts one or more electrodes located below the proof mass to provide a switch closure in response to the sensed acceleration. Electrical latching of the switch in the closed position is possible with an optional latching electrode. The MEM acceleration switch, which has applications for use as an environmental sensing device, can be fabricated using micromachining.

  1. RADIATION MEASURING DEVICES

    DOEpatents

    Bouricius, G.M.B.; Rusch, G.K.

    1960-03-22

    A radiation-measuring device is described having an a-c output. The apparatus has a high-energy particle source responsive to radiation flux disposed within a housing having a pair of collector plates. A potential gradient between the source and collector plates causes ions to flow to the plates. By means of electrostatic or magnetic deflection elements connected to an alternating potential, the ions are caused to flow alternately to each of the collector plates causing an a-c signal thereon.

  2. Advanced Resistive Exercise Device

    NASA Technical Reports Server (NTRS)

    Raboin, Jasen; Niebuhr, Jason; Cruz, Santana; Lamoreaux, chris

    2007-01-01

    The advanced resistive exercise device (ARED), now at the prototype stage of development, is a versatile machine that can be used to perform different customized exercises for which, heretofore, it has been necessary to use different machines. Conceived as a means of helping astronauts and others to maintain muscle and bone strength and endurance in low-gravity environments, the ARED could also prove advantageous in terrestrial settings (e.g., health clubs and military training facilities) in which many users are exercising simultaneously and there is heavy demand for use of exercise machines.

  3. Drop foot corrective device

    NASA Technical Reports Server (NTRS)

    Deis, B. C. (Inventor)

    1986-01-01

    A light weight, economical device to alleviate a plurality of difficulties encountered in walking by a victim suffering from a drop foot condition is discussed. A legband girdles the leg below the knee and above the calf providing an anchor point for the upper end of a ligament having its lower end attached to a toe of a shoe or a toe on the foot. The ligament is of such length that the foot is supported thereby and retained in a normal position during walking.

  4. Heat transfer device

    NASA Technical Reports Server (NTRS)

    Kalkbrenner, R. W. (Inventor)

    1974-01-01

    A heat transfer device is characterized by an hermetically sealed tubular housing including a tubular shell terminating in spaced end plates, and a tubular mesh wick concentrically arranged and operatively supported within said housing. The invention provides an improved wicking restraint formed as an elongated and radially expanded tubular helix concentrically related to the wick and adapted to be axially foreshortened and radially expanded into engagement with the wick in response to an axially applied compressive load. The wick is continuously supported in a contiguous relationship with the internal surfaces of the shell.

  5. Nanochanneled Device and Related Methods

    NASA Technical Reports Server (NTRS)

    Goodall, Randy (Inventor); Hosali, Sharath (Inventor); Grattoni, Alessandro (Inventor); Fine, Daniel (Inventor); Hudson, Lee (Inventor); Ferrari, Mauro (Inventor); Liu, Xuewu (Inventor); Medema, Ryan (Inventor)

    2013-01-01

    A nanochannel delivery device and method of manufacturing and use. The nanochannel delivery device comprises an inlet, an outlet, and a nanochannel. The nanochannel may be oriented parallel to the primary plane of the nanochannel delivery device. The inlet and outlet may be in direct fluid communication with the nanochannel.

  6. Evaluating transdermal alcohol measuring devices

    DOT National Transportation Integrated Search

    2007-11-01

    This report is an evaluation study of two types of transdermal devices that detect alcohol at the skin surface representing two types of electrochemical sensing technology. The AMS SCRAM ankle device and the Giner WrisTAS wrist device were worn...

  7. FDA's perspectives on cardiovascular devices.

    PubMed

    Chen, Eric A; Patel-Raman, Sonna M; O'Callaghan, Kathryn; Hillebrenner, Matthew G

    2009-06-01

    The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug & Cosmetic Act, Section 903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 http://www.fda.gov/opacom/laws/fdcact/fdctoc.htm). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA's review of extensive preclinical bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular device in a U.S. clinical trial.

  8. Graphene device and method of using graphene device

    DOEpatents

    Bouchiat, Vincent; Girit, Caglar; Kessler, Brian; Zettl, Alexander K.

    2015-08-11

    An embodiment of a graphene device includes a layered structure, first and second electrodes, and a dopant island. The layered structure includes a conductive layer, an insulating layer, and a graphene layer. The electrodes are coupled to the graphene layer. The dopant island is coupled to an exposed surface of the graphene layer between the electrodes. An embodiment of a method of using a graphene device includes providing the graphene device. A voltage is applied to the conductive layer of the graphene device. Another embodiment of a method of using a graphene device includes providing the graphene device without the dopant island. A dopant island is placed on an exposed surface of the graphene layer between the electrodes. A voltage is applied to the conductive layer of the graphene device. A response of the dopant island to the voltage is observed.

  9. Clamp-mount device

    NASA Technical Reports Server (NTRS)

    Clark, K. H. (Inventor)

    1983-01-01

    A clamp-mount device is disclosed for mounting equipment to an associated I-beam and the like structural member of the type having oppositely extending flanges wherein the device comprises a base and a pair of oppositely facing clamping members carried diagonally on the base clamping flanges therebetween and having flange receiving openings facing one another. Lock means are carried diagonally by the base opposite the clamping members locking the flanges in the clamping members. A resilient hub is carried centrally of the base engaging and biasing a back side of the flanges maintaining tightly clamped and facilitating use on vertical as well as horizontal members. The base turns about the hub to receive the flanges within the clamping members. Equipment may be secured to the base by any suitable means such as bolts in openings. Slidable gate latches secure the hinged locks in an upright locking position. The resilient hub includes a recess opening formed in the base and a rubber-like pad carried in this opening being depressably and rotatably carried therein.

  10. Thermoplastic tape compaction device

    DOEpatents

    Campbell, V.W.

    1994-12-27

    A device is disclosed for bonding a thermoplastic tape to a substrate to form a fully consolidated composite. This device has an endless chain associated with a frame so as to rotate in a plane that is perpendicular to a long dimension of the tape, the chain having pivotally connected chain links with each of the links carrying a flexible foot member that extends outwardly from the chain. A selected number of the foot members contact the tape, after the heating thereof, to cause the heated tape to bond to the substrate. The foot members are each a thin band of metal oriented transversely to the chain, with a flexibility and width and length to contact the tape so as to cause the tape to conform to the substrate to achieve consolidation of the tape and the substrate. A biased leaf-type spring within the frame bears against an inner surface of the chain to provide the compliant pressure necessary to bond the tape to the substrate. The chain is supported by sprockets on shafts rotatably supported in the frame and, in one embodiment, one of the shafts has a drive unit to produce rotation such that the foot members in contact with the tape move at the same speed as the tape. Cooling jets are positioned along the frame to cool the resultant consolidated composite. 5 figures.

  11. Thermoplastic tape compaction device

    DOEpatents

    Campbell, Vincent W.

    1994-01-01

    A device for bonding a thermoplastic tape to a substrate to form a fully consolidated composite. This device has an endless chain associated with a frame so as to rotate in a plane that is perpendicular to a long dimension of the tape, the chain having pivotally connected chain links with each of the links carrying a flexible foot member that extends outwardly from the chain. A selected number of the foot members contact the tape, after the heating thereof, to cause the heated tape to bond to the substrate. The foot members are each a thin band of metal oriented transversely to the chain, with a flexibility and width and length to contact the tape so as to cause the tape to conform to the substrate to achieve consolidation of the tape and the substrate. A biased leaf-type spring within the frame bears against an inner surface of the chain to provide the compliant pressure necessary to bond the tape to the substrate. The chain is supported by sprockets on shafts rotatably supported in the frame and, in one embodiment, one of the shafts has a drive unit to produce rotation such that the foot members in contact with the tape move at the same speed as the tape. Cooling jets are positioned along the frame to cool the resultant consolidated composite.

  12. Neuroelectric Virtual Devices

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin; Jorgensen, Charles

    2000-01-01

    This paper presents recent results in neuroelectric pattern recognition of electromyographic (EMG) signals used to control virtual computer input devices. The devices are designed to substitute for the functions of both a traditional joystick and keyboard entry method. We demonstrate recognition accuracy through neuroelectric control of a 757 class simulation aircraft landing at San Francisco International Airport using a virtual joystick as shown. This is accomplished by a pilot closing his fist in empty air and performing control movements that are captured by a dry electrode array on the arm which are then analyzed and routed through a flight director permitting full pilot outer loop control of the simulation. We then demonstrate finer grain motor pattern recognition through a virtual keyboard by having a typist tap his traders on a typical desk in a touch typist position. The EMG signals are then translated to keyboard presses and displayed. The paper describes the bioelectric pattern recognition methodology common to both examples. Figure 2 depicts raw EMG data from typing, the numeral '8' and the numeral '9'. These two gestures are very close in appearance and statistical properties yet are distinguishable by our hidden Kharkov model algorithms. Extensions of this work to NASA emissions and robotic control are considered.

  13. Thermoplastic tape compaction device

    SciTech Connect

    Campbell, V.W.

    1994-12-27

    A device is disclosed for bonding a thermoplastic tape to a substrate to form a fully consolidated composite. This device has an endless chain associated with a frame so as to rotate in a plane that is perpendicular to a long dimension of the tape, the chain having pivotally connected chain links with each of the links carrying a flexible foot member that extends outwardly from the chain. A selected number of the foot members contact the tape, after the heating thereof, to cause the heated tape to bond to the substrate. The foot members are each a thin bandmore » of metal oriented transversely to the chain, with a flexibility and width and length to contact the tape so as to cause the tape to conform to the substrate to achieve consolidation of the tape and the substrate. A biased leaf-type spring within the frame bears against an inner surface of the chain to provide the compliant pressure necessary to bond the tape to the substrate. The chain is supported by sprockets on shafts rotatably supported in the frame and, in one embodiment, one of the shafts has a drive unit to produce rotation such that the foot members in contact with the tape move at the same speed as the tape. Cooling jets are positioned along the frame to cool the resultant consolidated composite. 5 figures.« less

  14. Devices as destination therapy.

    PubMed

    Kukuy, Eugene L; Oz, Mehmet C; Rose, Eric A; Naka, Yoshifumi

    2003-02-01

    The use of circulatory support as destination therapy has been a goal for the treatment of endstage heart failure for several decades. Current investigations are evaluating several circulatory pumps with that particular objective. With continued modification of design, the current and future pumps will become more reliable and provide improved quality of life to patients in need of mechanical circulatory assistance. The new pumps on the horizon specifically address reliability, size, and cost, and are based on the centrifugal system. These devices use the Maglev (Magnetic Levitation) concept that allows for frictionless pumping, low thrombogenicity, minimal noise, and increased durability. Further research with this goal in mind and support from the federal government will be the key to the future use of circulatory assistance as destination therapy for heart failure patients. In addition, the cost-effectiveness of these devices will need to be maintained as the technology improves, as in any new technology that confronts a more intuitive option like the native heart.

  15. Preface: Heterostructure terahertz devices

    NASA Astrophysics Data System (ADS)

    Ryzhii, Victor

    2008-08-01

    The terahertz (THz) range of frequencies is borderline between microwave electronics and photonics. It corresponds to the frequency bands of molecular and lattice vibrations in gases, fluids, and solids. The importance of the THz range is in part due to numerous potential and emerging applications which include imaging and characterization, detection of hazardous substances, environmental monitoring, radio astronomy, covert inter-satellite communications, as well as biological and medical applications. During the last decades marked progress has been achieved in the development, fabrication, and practical implementation of THz devices and systems. This is primarily owing to the utilization of gaseous and free electron lasers and frequency converters using nonlinear optical phenomena as sources of THz radiation. However, such devices and hence the systems based on them are fairly cumbersome. This continuously stimulates an extensive search for new compact and efficient THz sources based on semiconductor heterostructures. Despite tremendous efforts lasting several decades, the so-called THz gap unbridged by semiconductor heterostructure electron and optoelectron devices still exists providing appropriate levels of power of the generated THz radiation. The invention and realization of quantum cascade lasers made of multiple quantum-well heterostructures already resulted in the partial solution of the problem in question, namely, in the successful coverage of the high-frequency portion of the THz gap (2-3 THz and higher). Further advancement to lower frequencies meets, perhaps, fundamental difficulties. All this necessitates further extensive theoretical and experimental studies of more or less traditional and novel semiconductor heterostructures as a basis for sources of THz radiation. This special issue includes 11 excellent original papers submitted by several research teams representing 14 institutions in Europe, America, and Asia. Several device concepts which

  16. Fluid flow monitoring device

    DOEpatents

    McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.

    1993-11-30

    A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.

  17. Charge coupled devices

    NASA Technical Reports Server (NTRS)

    Walker, J. W.; Hornbeck, L. J.; Stubbs, D. P.

    1977-01-01

    The results are presented of a program to design, fabricate, and test CCD arrays suitable for operation in an electron-bombarded mode. These intensified charge coupled devices have potential application to astronomy as photon-counting arrays. The objectives of this program were to deliver arrays of 250 lines of 400 pixels each and some associated electronics. Some arrays were delivered on tube-compatible headers and some were delivered after incorporation in vacuum tubes. Delivery of these devices required considerable improvements to be made in the processing associated with intensified operation. These improvements resulted in a high yield in the thinning process, reproducible results in the accumulation process, elimination of a dark current source in the accumulation process, solution of a number of header related problems, and the identification of a remaining major source of dark current. Two systematic failure modes were identified and protective measures established. The effects of tube processing on the arrays in the delivered ICCDs were determined and are reported along with the characterization data on the arrays.

  18. Micro-Organ Device

    NASA Technical Reports Server (NTRS)

    Sun, Wei (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Holtorf, Heidi L. (Inventor); Leslie, Julia (Inventor); Culbertson, Christopher (Inventor); Gonda, Steve R. (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  19. Micro-organ device

    NASA Technical Reports Server (NTRS)

    von Gustedt-Gonda, legal representative, Iris (Inventor); Holtorf, Heidi L. (Inventor); Gonda, Steve R. (Inventor); Leslie, Julia (Inventor); Chang, Robert C. (Inventor); Sun, Wei (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  20. EDITORIAL: Photonic Crystal Devices

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Pallab K.

    2007-05-01

    The engineering of electromagnetic modes at optical frequencies in artificial dielectric structures with periodic and random variation of the refractive index, enabling control of the radiative properties of the materials and photon localization, was first proposed independently by Yablonovitch and John in 1987. It is possible to control the flow of light in the periodic dielectric structures, known as photonic crystals (PC). As light waves scatter within the photonic crystal, destructive interference cancels out light of certain wavelengths, thereby forming a photonic bandgap, similar to the energy bandgap for electron waves in a semiconductor. Photons whose energies lie within the gap cannot propagate through the periodic structure. This property can be used to make a low-loss cavity. If a point defect, such as one or more missing periods, is introduced into the periodic structure a region is obtained within which the otherwise forbidden wavelengths can be locally trapped. This property can be used to realize photonic microcavities. Similarly, a line of defects can serve as a waveguide. While the realization of three-dimensional (3D) photonic crystals received considerable attention initially, planar two-dimensional (2D) structures are currently favoured because of their relative ease of fabrication. 2D photonic crystal structures provide most of the functionality of 3D structures. These attributes have generated worldwide research and development of sub-μm and μm size active and passive photonic devices such as single-mode and non- classical light sources, guided wave devices, resonant cavity detection, and components for optical communication. More recently, photonic crystal guided wave devices are being investigated for application in microfludic and biochemical sensing. Photonic crystal devices have been realized with bulk, quantum well and quantum dot active regions. The Cluster of articles in this issue of Journal of Physics D: Applied Physics provides a

  1. Stretchable and foldable electronic devices

    DOEpatents

    Rogers, John A; Huang, Yonggang; Ko, Heung Cho; Stoykovich, Mark; Choi, Won Mook; Song, Jizhou; Ahn, Jong Hyun; Kim, Dae Hyeong

    2013-10-08

    Disclosed herein are stretchable, foldable and optionally printable, processes for making devices and devices such as semiconductors, electronic circuits and components thereof that are capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Strain isolation layers provide good strain isolation to functional device layers. Multilayer devices are constructed to position a neutral mechanical surface coincident or proximate to a functional layer having a material that is susceptible to strain-induced failure. Neutral mechanical surfaces are positioned by one or more layers having a property that is spatially inhomogeneous, such as by patterning any of the layers of the multilayer device.

  2. Stretchable and foldable electronic devices

    DOEpatents

    Rogers, John A; Huang, Yonggang; Ko, Heung Cho; Stoykovich, Mark; Choi, Won Mook; Song, Jizhou; Ahn, Jong Hyun; Kim, Dae Hyeong

    2014-12-09

    Disclosed herein are stretchable, foldable and optionally printable, processes for making devices and devices such as semiconductors, electronic circuits and components thereof that are capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Strain isolation layers provide good strain isolation to functional device layers. Multilayer devices are constructed to position a neutral mechanical surface coincident or proximate to a functional layer having a material that is susceptible to strain-induced failure. Neutral mechanical surfaces are positioned by one or more layers having a property that is spatially inhomogeneous, such as by patterning any of the layers of the multilayer device.

  3. An All Oxide-Based Imperceptible Thin-Film Transistor with Humidity Sensing Properties

    PubMed Central

    Kim, Kyung Su; Ahn, Cheol Hyoun; Kang, Won Jun; Cho, Sung Woon; Jung, Sung Hyeon; Yoon, Dae Ho; Cho, Hyung Koun

    2017-01-01

    We have examined the effects of oxygen content and thickness in sputtered InSnO (ITO) electrodes, especially for the application of imperceptible amorphous-InGaZnO (a-IGZO) thin-film transistors (TFTs) in humidity sensors. The imperceptible a-IGZO TFT with 50-nm ITO electrodes deposited at Ar:O2 = 29:0.3 exhibited good electrical performances with Vth of −0.23 V, SS of 0.34 V/dec, µFE of 7.86 cm2/V∙s, on/off ratio of 8.8 × 107, and has no degradation for bending stress up to a 3.5-mm curvature. The imperceptible oxide TFT sensors showed the highest sensitivity for the low and wide gate bias of −1~2 V under a wide range of relative humidity (40–90%) at drain voltage 1 V, resulting in low power consumption by the sensors. Exposure to water vapor led to a negative shift in the threshold voltage (or current enhancement), and an increase in relative humidity induced continuous threshold voltage shift. In particular, compared to conventional resistor-type sensors, the imperceptible oxide TFT sensors exhibited extremely high sensitivity from a current amplification of >103. PMID:28772888

  4. An All Oxide-Based Imperceptible Thin-Film Transistor with Humidity Sensing Properties.

    PubMed

    Kim, Kyung Su; Ahn, Cheol Hyoun; Kang, Won Jun; Cho, Sung Woon; Jung, Sung Hyeon; Yoon, Dae Ho; Cho, Hyung Koun

    2017-05-13

    We have examined the effects of oxygen content and thickness in sputtered InSnO (ITO) electrodes, especially for the application of imperceptible amorphous-InGaZnO ( a -IGZO) thin-film transistors (TFTs) in humidity sensors. The imperceptible a -IGZO TFT with 50-nm ITO electrodes deposited at Ar:O₂ = 29:0.3 exhibited good electrical performances with V th of -0.23 V, SS of 0.34 V/dec, µ FE of 7.86 cm²/V∙s, on/off ratio of 8.8 × 10⁷, and has no degradation for bending stress up to a 3.5-mm curvature. The imperceptible oxide TFT sensors showed the highest sensitivity for the low and wide gate bias of -1~2 V under a wide range of relative humidity (40-90%) at drain voltage 1 V, resulting in low power consumption by the sensors. Exposure to water vapor led to a negative shift in the threshold voltage (or current enhancement), and an increase in relative humidity induced continuous threshold voltage shift. In particular, compared to conventional resistor-type sensors, the imperceptible oxide TFT sensors exhibited extremely high sensitivity from a current amplification of >10³.

  5. Cybersecurity for Connected Diabetes Devices

    PubMed Central

    Klonoff, David C.

    2015-01-01

    Diabetes devices are increasingly connected wirelessly to each other and to data-displaying reader devices. Threats to the accurate flow of information and commands may compromise the function of these devices and put their users at risk of health complications. Sound cybersecurity of connected diabetes devices is necessary to maintain confidentiality, integrity, and availability of the data and commands. Diabetes devices can be hacked by unauthorized agents and also by patients themselves to extract data that are not automatically provided by product software. Unauthorized access to connected diabetes devices has been simulated and could happen in reality. A cybersecurity standard designed specifically for connected diabetes devices will improve the safety of these products and increase confidence of users that the products will be secure. PMID:25883162

  6. Flexible packaging for microelectronic devices

    SciTech Connect

    Anderson, Benjamin John; Nielson, Gregory N.; Cruz-Campa, Jose Luis

    An apparatus, method, and system, the apparatus and system including a flexible microsystems enabled microelectronic device package including a microelectronic device positioned on a substrate; an encapsulation layer encapsulating the microelectronic device and the substrate; a protective layer positioned around the encapsulating layer; and a reinforcing layer coupled to the protective layer, wherein the substrate, encapsulation layer, protective layer and reinforcing layer form a flexible and optically transparent package around the microelectronic device. The method including encapsulating a microelectronic device positioned on a substrate within an encapsulation layer; sealing the encapsulated microelectronic device within a protective layer; and coupling themore » protective layer to a reinforcing layer, wherein the substrate, encapsulation layer, protective layer and reinforcing layer form a flexible and optically transparent package around the microelectronic device.« less

  7. Cybersecurity for Connected Diabetes Devices.

    PubMed

    Klonoff, David C

    2015-04-16

    Diabetes devices are increasingly connected wirelessly to each other and to data-displaying reader devices. Threats to the accurate flow of information and commands may compromise the function of these devices and put their users at risk of health complications. Sound cybersecurity of connected diabetes devices is necessary to maintain confidentiality, integrity, and availability of the data and commands. Diabetes devices can be hacked by unauthorized agents and also by patients themselves to extract data that are not automatically provided by product software. Unauthorized access to connected diabetes devices has been simulated and could happen in reality. A cybersecurity standard designed specifically for connected diabetes devices will improve the safety of these products and increase confidence of users that the products will be secure. © 2015 Diabetes Technology Society.

  8. Optical Indoor Positioning System Based on TFT Technology.

    PubMed

    Gőzse, István

    2015-12-24

    A novel indoor positioning system is presented in the paper. Similarly to the camera-based solutions, it is based on visual detection, but it conceptually differs from the classical approaches. First, the objects are marked by LEDs, and second, a special sensing unit is applied, instead of a camera, to track the motion of the markers. This sensing unit realizes a modified pinhole camera model, where the light-sensing area is fixed and consists of a small number of sensing elements (photodiodes), and it is the hole that can be moved. The markers are tracked by controlling the motion of the hole, such that the light of the LEDs always hits the photodiodes. The proposed concept has several advantages: Apart from its low computational demands, it is insensitive to the disturbing ambient light. Moreover, as every component of the system can be realized by simple and inexpensive elements, the overall cost of the system can be kept low.

  9. Optical Indoor Positioning System Based on TFT Technology

    PubMed Central

    Gőzse, István

    2015-01-01

    A novel indoor positioning system is presented in the paper. Similarly to the camera-based solutions, it is based on visual detection, but it conceptually differs from the classical approaches. First, the objects are marked by LEDs, and second, a special sensing unit is applied, instead of a camera, to track the motion of the markers. This sensing unit realizes a modified pinhole camera model, where the light-sensing area is fixed and consists of a small number of sensing elements (photodiodes), and it is the hole that can be moved. The markers are tracked by controlling the motion of the hole, such that the light of the LEDs always hits the photodiodes. The proposed concept has several advantages: Apart from its low computational demands, it is insensitive to the disturbing ambient light. Moreover, as every component of the system can be realized by simple and inexpensive elements, the overall cost of the system can be kept low. PMID:26712753

  10. Monitored separation device

    NASA Technical Reports Server (NTRS)

    Fox, George Edward (Inventor); Jackson, George William (Inventor); Willson, Richard Coale (Inventor)

    2011-01-01

    A device for separating and purifying useful quantities of particles comprises: a. an anolyte reservoir connected to an anode, the anolyte reservoir containing an electrophoresis buffer; b. a catholyte reservoir connected to a cathode, the catholyte reservoir also containing the electrophoresis buffer; c. a power supply connected to the anode and to the cathode; d. a column having a first end inserted into the anolyte reservoir, a second end inserted into the catholyte reservoir, and containing a separation medium; e. a light source; f. a first optical fiber having a first fiber end inserted into the separation medium, and having a second fiber end connected to the light source; g. a photo detector; h. a second optical fiber having a third fiber end inserted into the separation medium, and having a fourth fiber end connected to the photo detector; and i. an ion-exchange membrane in the anolyte reservoir.

  11. Tunable surface plasmon devices

    DOEpatents

    Shaner, Eric A [Rio Rancho, NM; Wasserman, Daniel [Lowell, MA

    2011-08-30

    A tunable extraordinary optical transmission (EOT) device wherein the tunability derives from controlled variation of the dielectric constant of a semiconducting material (semiconductor) in evanescent-field contact with a metallic array of sub-wavelength apertures. The surface plasmon resonance wavelength can be changed by changing the dielectric constant of the dielectric material. In embodiments of this invention, the dielectric material is a semiconducting material. The dielectric constant of the semiconducting material in the metal/semiconductor interfacial region is controllably adjusted by adjusting one or more of the semiconductor plasma frequency, the concentration and effective mass of free carriers, and the background high-frequency dielectric constant in the interfacial region. Thermal heating and/or voltage-gated carrier-concentration changes may be used to variably adjust the value of the semiconductor dielectric constant.

  12. CUSP-PINCH DEVICE

    DOEpatents

    Baker, W.R.; Watteau, J.P.H.

    1962-06-01

    An ion-electron plasma heating device of the pinch tube class is designed with novel means for counteracting the instabilities of an ordinary linear pinch discharge. A plasma-forming discharge is created between two spacedapart coaxial electiodes through a gas such as deuterium. A pair of spaced coaxial magnetic field coils encircle the discharge and carry opposing currents so that a magnetic field having a cuspate configuration is created around the plasma, the field being formed after the plasma has been established but before significant instability arises. Thus, containment time is increased and intensified heating is obtained. In addition to the pinch compression heating additional heating is obtained by high-frequency magnetic field modulation. (AEC)

  13. Value contamination avoidance devices

    NASA Technical Reports Server (NTRS)

    Endicott, D. L.

    1975-01-01

    Mechanical redesign methods were used to minimize contamination damage of conventional fluid components and a contamination separator device was developed for long term reusable space vehicles. These were incorporated into an existing 50.8 mm poppet valve and tested for damage tolerance in a full size open loop flow system with gaseous and liquid nitrogen. Cyclic and steady flow conditions were tested with particles of 125 to 420 micrometers aluminum oxide dispersed in the test fluids. Nonflow life tests (100,000 cycles) were made with two valve configurations in gaseous hydrogen. The redesigned valve had an acceptable cycle life and improved tolerance to contamination damage when the primary sealing surfaces were coated with thin coatings of hard plastic (Teflon S and Kynar). Analytical studies and flow testing were completed of four different versions of the separator. overall separation efficiencies in the 55-90% range were measured with these non-optimum configurations.

  14. Tube coupling device

    NASA Technical Reports Server (NTRS)

    Myers, William N. (Inventor); Hein, Leopold A. (Inventor)

    1987-01-01

    A first annular ring of a tube coupling device has a keyed opening sized to fit around the nut region of a male coupling, and a second annular ring has a keyed opening sized to fit around the nut of a female coupling. Each ring has mating ratchet teeth and these rings are biased together, thereby engaging these teeth and preventing rotation of these rings. This in turn prevents the rotation of the male nut region with respect to the female nut. For tube-to-bulkhead locking, one facet of one ring is notched, and a pin is pressed into an opening in the bulkhead. This pin is sized to fit within one of the notches in the ring, thereby preventing rotation of this ring with respect to the bulkhead.

  15. Capacitance measuring device

    DOEpatents

    Andrews, W.H. Jr.

    1984-08-01

    A capacitance measuring circuit is provided in which an unknown capacitance is measured by comparing the charge stored in the unknown capacitor with that stored in a known capacitance. Equal and opposite voltages are repetitively simultaneously switched onto the capacitors through an electronic switch driven by a pulse generator to charge the capacitors during the ''on'' portion of the cycle. The stored charge is compared by summing discharge currents flowing through matched resistors at the input of a current sensor during the ''off'' portion of the switching cycle. The net current measured is thus proportional to the difference in value of the two capacitances. The circuit is capable of providing much needed accuracy and stability to a great variety of capacitance-based measurement devices at a relatively low cost.

  16. Materials for optoelectronic devices

    DOEpatents

    Shiang, Joseph John; Smigelski, Jr., Paul Michael

    2015-01-27

    Energy efficient optoelectronic devices include an electroluminescent layer containing a polymer made up of structural units of formula I and II; ##STR00001## wherein R.sup.1 and R.sup.2 are independently C.sub.22-44 hydrocarbyl, C.sub.22-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, oxaalkylaryl, or a combination thereof; R.sup.3 and R.sup.4 are independently H, C.sub.1-44 hydrocarbyl or C.sub.1-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, or R.sup.3 and R.sup.4, taken together, form a C.sub.2-10 monocyclic or bicyclic ring containing up to three S, N, O, P, or Si heteroatoms; and X is S, Se, or a combination thereof.

  17. Tool setting device

    DOEpatents

    Brown, Raymond J.

    1977-01-01

    The present invention relates to a tool setting device for use with numerically controlled machine tools, such as lathes and milling machines. A reference position of the machine tool relative to the workpiece along both the X and Y axes is utilized by the control circuit for driving the tool through its program. This reference position is determined for both axes by displacing a single linear variable displacement transducer (LVDT) with the machine tool through a T-shaped pivotal bar. The use of the T-shaped bar allows the cutting tool to be moved sequentially in the X or Y direction for indicating the actual position of the machine tool relative to the predetermined desired position in the numerical control circuit by using a single LVDT.

  18. Electrical safety device

    DOEpatents

    White, David B.

    1991-01-01

    An electrical safety device for use in power tools that is designed to automatically discontinue operation of the power tool upon physical contact of the tool with a concealed conductive material. A step down transformer is used to supply the operating power for a disconnect relay and a reset relay. When physical contact is made between the power tool and the conductive material, an electrical circuit through the disconnect relay is completed and the operation of the power tool is automatically interrupted. Once the contact between the tool and conductive material is broken, the power tool can be quickly and easily reactivated by a reset push button activating the reset relay. A remote reset is provided for convenience and efficiency of operation.

  19. Multichannel optical sensing device

    DOEpatents

    Selkowitz, S.E.

    1985-08-16

    A multichannel optical sensing device is disclosed, for measuring the outdoor sky luminance or illuminance or the luminance or illuminance distribution in a room, comprising a plurality of light receptors, an optical shutter matrix including a plurality of liquid crystal optical shutter elements operable by electrical control signals between light transmitting and light stopping conditions, fiber optical elements connected between the receptors and the shutter elements, a microprocessor based programmable control unit for selectively supplying control signals to the optical shutter elements in a programmable sequence, a photodetector including an optical integrating spherical chamber having an input port for receiving the light from the shutter matrix and at least one detector element in the spherical chamber for producing output signals corresponding to the light, and output units for utilizing the output signals including a storage unit having a control connection to the microprocessor based programmable control unit for storing the output signals under the sequence control of the programmable control unit.

  20. Multichannel optical sensing device

    DOEpatents

    Selkowitz, Stephen E.

    1990-01-01

    A multichannel optical sensing device is disclosed, for measuring the outr sky luminance or illuminance or the luminance or illuminance distribution in a room, comprising a plurality of light receptors, an optical shutter matrix including a plurality of liquid crystal optical shutter elements operable by electrical control signals between light transmitting and light stopping conditions, fiber optic elements connected between the receptors and the shutter elements, a microprocessor based programmable control unit for selectively supplying control signals to the optical shutter elements in a programmable sequence, a photodetector including an optical integrating spherical chamber having an input port for receiving the light from the shutter matrix and at least one detector element in the spherical chamber for producing output signals corresponding to the light, and output units for utilizing the output signals including a storage unit having a control connection to the microprocessor based programmable control unit for storing the output signals under the sequence control of the programmable control unit.

  1. Personal annunciation device

    DOEpatents

    Angelo, Peter [Oak Ridge, TN; Younkin, James [Oak Ridge, TN; DeMint, Paul [Kingston, TN

    2011-01-25

    A personal annunciation device (PAD) providing, in an area of interest, compensatory annunciation of the presence of an abnormal condition in a hazardous area and accountability of the user of the PAD. Compensatory annunciation supplements primary annunciation provided by an emergency notification system (ENS). A detection system detects an abnormal condition, and a wireless transmission system transmits a wireless transmission to the PAD. The PAD has a housing enclosing the components of the PAD including a communication module for receiving the wireless transmission, a power supply, processor, memory, annunciation system, and RFID module. The RFID module has an RFID receiver that listens for an RFID transmission from an RFID reader disposed in a portal of an area of interest. The PAD identifies the transmission and changes its operating state based on the transmission. The RFID readers recognize, record, and transmit the state of the PAD to a base station providing accountability of the wearer.

  2. Efficient thermoelectric device

    NASA Technical Reports Server (NTRS)

    Ila, Daryush (Inventor)

    2010-01-01

    A high efficiency thermo electric device comprising a multi nanolayer structure of alternating insulator and insulator/metal material that is irradiated across the plane of the layer structure with ionizing radiation. The ionizing radiation produces nanocrystals in the layered structure that increase the electrical conductivity and decrease the thermal conductivity thereby increasing the thermoelectric figure of merit. Figures of merit as high as 2.5 have been achieved using layers of co-deposited gold and silicon dioxide interspersed with layers of silicon dioxide. The gold to silicon dioxide ratio was 0.04. 5 MeV silicon ions were used to irradiate the structure. Other metals and insulators may be substituted. Other ionizing radiation sources may be used. The structure tolerates a wide range of metal to insulator ratio.

  3. Light emitting ceramic device

    DOEpatents

    Valentine, Paul; Edwards, Doreen D.; Walker, Jr., William John; Slack, Lyle H.; Brown, Wayne Douglas; Osborne, Cathy; Norton, Michael; Begley, Richard

    2010-05-18

    A light-emitting ceramic based panel, hereafter termed "electroceramescent" panel, is herein claimed. The electroceramescent panel is formed on a substrate providing mechanical support as well as serving as the base electrode for the device. One or more semiconductive ceramic layers directly overlay the substrate, and electrical conductivity and ionic diffusion are controlled. Light emitting regions overlay the semiconductive ceramic layers, and said regions consist sequentially of a layer of a ceramic insulation layer and an electroluminescent layer, comprised of doped phosphors or the equivalent. One or more conductive top electrode layers having optically transmissive areas overlay the light emitting regions, and a multi-layered top barrier cover comprising one or more optically transmissive non-combustible insulation layers overlay said top electrode regions.

  4. Capillary interconnect device

    DOEpatents

    Renzi, Ronald F.

    2007-12-25

    A manifold for connecting external capillaries to the inlet and/or outlet ports of a microfluidic device for high pressure applications is provided. The fluid connector for coupling at least one fluid conduit to a corresponding port of a substrate that includes: (i) a manifold comprising one or more channels extending therethrough wherein each channel is at least partially threaded, (ii) one or more threaded ferrules each defining a bore extending therethrough with each ferrule supporting a fluid conduit wherein each ferrule is threaded into a channel of the manifold, (iii) a substrate having one or more ports on its upper surface wherein the substrate is positioned below the manifold so that the one or more ports is aligned with the one or more channels of the manifold, and (iv) means for applying an axial compressive force to the substrate to couple the one or more ports of the substrate to a corresponding proximal end of a fluid conduit.

  5. Module isolation devices

    DOEpatents

    Carolan, Michael Francis; Cooke, John Albert; Buzinski, Michael David

    2010-04-27

    A gas flow isolation device includes a gas flow isolation valve movable from an opened condition to a closed condition. The module isolation valve in one embodiment includes a rupture disk in flow communication with a flow of gas when the module isolation valve is in an opened condition. The rupture disk ruptures when a predetermined pressure differential occurs across it causing the isolation valve to close. In one embodiment the valve is mechanically linked to the rupture disk to maintain the valve in an opened condition when the rupture disk is intact, and which permits the valve to move into a closed condition when the rupture disk ruptures. In another embodiment a crushable member maintains the valve in an open condition, and the flow of gas passed the valve upon rupturing of the rupture disk compresses the crushable member to close the isolation valve.

  6. Programmable logic devices

    NASA Astrophysics Data System (ADS)

    Jacobs, J. L.

    1993-04-01

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

  7. Air bag restraint device

    DOEpatents

    Marts, D.J.; Richardson, J.G.

    1995-10-17

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle`s rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump. 8 figs.

  8. Air bag restraint device

    DOEpatents

    Marts, Donna J.; Richardson, John G.

    1995-01-01

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle's rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump.

  9. False color viewing device

    DOEpatents

    Kronberg, J.W.

    1992-10-20

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage. 7 figs.

  10. False color viewing device

    DOEpatents

    Kronberg, James W.

    1992-01-01

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.

  11. False color viewing device

    DOEpatents

    Kronberg, J.W.

    1991-05-08

    This invention consists of a viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching, the user`s eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.

  12. Polarization Perception Device

    NASA Technical Reports Server (NTRS)

    Whitehead, Victor S. (Inventor); Coulson, Kinsell L. (Inventor)

    1997-01-01

    A polarization perception device comprises a base and a polarizing filter having opposite broad sides and a centerline perpendicular thereto. The filter is mounted on the base for relative rotation and with a major portion of the area of the filter substantially unobstructed on either side. A motor on the base automatically moves the filter angularly about its centerline at a speed slow enough to permit changes in light transmission by virtue of such movement to be perceived as light-dark pulses by a human observer, but fast enough so that the light phase of each such pulse occurs prior to fading of the light phase image of the preceding pulse from the observer's retina. In addition to an observer viewing a scene in real time through the filter while it is so angularly moved, or instead of such observation, the scene can be photographed, filmed or taped by a camera whose lens is positioned behind the filter.

  13. Polarization perception device

    NASA Technical Reports Server (NTRS)

    Whitehead, Victor S. (Inventor); Coulson, Kinsel L. (Inventor)

    1992-01-01

    A polarization perception device comprises a base and a polarizing filter having opposite broad sides and a centerline perpendicular thereto. The filter is mounted on the base for relative rotation and with a major portion of the area of the filter substantially unobstructed on either side. A motor on the base automatically moves the filter angularly about its centerline at a speed slow enough to permit changes in light transmission by virtue of such movement to be perceived as light-dark pulses by a human observer, but fast enough so that the light phase of each such pulse occurs prior to fading of the light phase image of the preceding pulse from the observer's retina. In addition to an observer viewing a scene in real time through the filter while it is so angularly moved, or instead of such observation, the scene can be photographed, filmed or taped by a camera whose lens is positioned behind the filter.

  14. TWO-SPEED DEVICE

    DOEpatents

    Brunson, G.S. Jr.

    1961-04-01

    A two-speed device is described comprising a two-part stop engageable with a follower. The two-pant stop comprises first and second members in threaded engagement with each other. The first member is restrained against rotation but is free to move longitudinally, and the second member is free to move arially and rotatively. Means are provided to impart rotation to the second member. The follower is engageable first with an end of one member and then with the corresponding end of the other member after some relative longitudinal movement of the members with respect to one another due to the rotation of the second member and the holding of the first member against rotation.

  15. Cathodochromic storage device

    NASA Technical Reports Server (NTRS)

    Bosomworth, D. R.; Moles, W. H.

    1969-01-01

    A memory and display device has been developed by combing a fast phosphor layer with a cathodochromic layer in a cathode ray tube. Images are stored as patterns of electron beam induced optical density in the cathodo-chromic material. The stored information is recovered by exciting the backing, fast phosphor layer with a constant current electron beam and detecting the emitted radiation which is modulated by absorption in the cathodochromic layer. The storage can be accomplished in one or more TV frames (1/30 sec each). More than 500 TV line resolution and close to 2:1 contrast ratio are possible. The information storage time in a dark environment is approximately 24 hours. A reconstituted (readout) electronic video signal can be generated continuously for times in excess of 10 minutes or periodically for several hours.

  16. Linear encoding device

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B. (Inventor)

    1993-01-01

    A Linear Motion Encoding device for measuring the linear motion of a moving object is disclosed in which a light source is mounted on the moving object and a position sensitive detector such as an array photodetector is mounted on a nearby stationary object. The light source emits a light beam directed towards the array photodetector such that a light spot is created on the array. An analog-to-digital converter, connected to the array photodetector is used for reading the position of the spot on the array photodetector. A microprocessor and memory is connected to the analog-to-digital converter to hold and manipulate data provided by the analog-to-digital converter on the position of the spot and to compute the linear displacement of the moving object based upon the data from the analog-to-digital converter.

  17. Rotary encoding device

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B. (Inventor)

    1993-01-01

    A device for position encoding of a rotating shaft in which a polygonal mirror having a number of facets is mounted to the shaft and a light beam is directed towards the facets is presented. The facets of the polygonal mirror reflect the light beam such that a light spot is created on a linear array detector. An analog-to-digital converter is connected to the linear array detector for reading the position of the spot on the linear array detector. A microprocessor with memory is connected to the analog-to-digital converter to hold and manipulate the data provided by the analog-to-digital converter on the position of the spot and to compute the position of the shaft based upon the data from the analog-to-digital converter.

  18. METAL RESISTIVITY MEASURING DEVICE

    DOEpatents

    Renken, J. Jr.; Myers, R.G.

    1960-12-20

    An eddy current device is offered for detecting discontinuities in metal samples. Alternate short and long duration pulses are inductively applied to a metal sample via the outer coil of a probe. The long pulses give a resultant signal from the metal sample responsive to probe-tosample spacing and discontinuities within the sample and the shont pulses give a resultant signal responsive only to probe -to-sample spacing. The inner coil of the probe detects the two resultant signals and transmits them to a separation network where the two signals are separated. The two separated signals are then transmitted to a compensation network where the detected signals due to the short pulses are used to compensate for variations due to probe-to-sample spacing contained in the detected signals from the long pulses. Thus, a resultant signal is obtained responsive to discontinuities within the sample and independent of probe-to- sample spacing.

  19. Metal Resistivity Measuring Device

    DOEpatents

    Renken, Jr, C. J.; Myers, R. G.

    1960-12-20

    An eddy current device is designed for detecting discontinuities in metal samples. Alternate short and long duration pulses are inductively applied to a metal sample via the outer coil of a probe. The lorg pulses give a resultant signal from the metal sample responsive to probe-tosample spacing and discontinuities with the sample, and the short pulses give a resultant signal responsive only to probe-to-sample spacing. The inner coil of the probe detects the two resultant signals and transmits them to a separation network where the two signals are separated. The two separated signals are then transmitted to a compensation network where the detected signals due to the short pulses are used to compensate for variations due to probeto-sample spacing contained in the detected signals from the long pulses. Thus a resultant signal is obtained responsive to discontinuities within the sample and independent of probe-to- sample spacing.

  20. Pressure Relief Devices

    NASA Astrophysics Data System (ADS)

    Manha, William D.

    2010-09-01

    Pressure relief devices are used in pressure systems and on pressure vessels to prevent catastrophic rupture or explosion from excessive pressure. Pressure systems and pressure vessels have manufacturers maximum rated operating pressures or maximum design pressures(MDP) for which there are relatively high safety factors and minimum risk of rupture or explosion. Pressure systems and pressure vessels that have a potential to exceed the MDP by being connected to another higher pressure source, a compressor, or heat to water(boiler) are required to have over-pressure protecting devices. Such devices can be relief valves and/or burst discs to safely relieve potentially excessive pressure and prevent unacceptable ruptures and explosions which result in fail-safe pressure systems and pressure vessels. Common aerospace relief valve and burst disc requirements and standards will be presented. This will include the NASA PSRP Interpretation Letter TA-88-074 Fault Tolerance of Systems Using Specially Certified Burst Disks that dictates burst disc requirements for payloads on Shuttle. Two recent undesirable manned space payloads pressure relief devices and practices will be discussed, as well as why these practices should not be continued. One example for discussion is the use of three burst discs that have been placed in series to comply with safety requirements of three controls to prevent a catastrophic hazard of the over-pressurization and rupture of pressure system and/or vessels. The cavities between the burst discs are evacuated and are the reference pressures for activating the two upstream burst discs. If the upstream burst disc leaks into the reference cavity, the reference pressure increases and it can increase the burst disc activating pressure and potentially result in the burst disc assembly being ineffective for over pressure protection. The three burst discs-in-series assembly was found acceptable because the burst discs are designed for minimum risk(DFMR) of