Browsing by Author "Lin, J. C."

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Characteristics of Zinc Oxide Thin Film Transistors Fabricated by Location-Controlled Hydrothermal Method
(2010)
Yang, P. Y.
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Wang, J. L.
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Tsai, W. C.
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Wang, S. J.
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Chen, P. C.
In this paper, high-performance Zinc oxide (ZnO) thin-film transistors (TFTs) with bottom-gate (BG) structure and artificially location-controlled lateral grain growth have been prepared by low-temperature hydrothermal method. As the proper design of source/drain structure of ZnO/Ti/Pt thin films, the lateral grain growth can be artificially controlled in the desired location and the vertical grain boundary perpendicular to the current flow in the channel region can be reduced to single one. As compared with the conventional sputtered ZnO BG-TFTs, the proposed location-controlled hydrothermal ZnO BG-TFTs (W/L = 250 mu m/10 mu m) demonstrated the higher field-effect mobility of 6.09 cm(2)/V.s, lower threshold voltage of 3.67 V, larger on/off current ratio above 10(6), and superior current drivability, which can be attributed to the high-quality ZnO thin films with the reduced vertical grain boundaries in the channel region.
Enhancement-Mode GaN MIS-HEMTs with HfLaOx Gate Insulator
(2016)
Lin, Y. C.
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Lin, J. C.
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Lin, Y.
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Wu, C. H.
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Huang, Y. X.
Evaluation of GaN HEMT with Field Plate for Reliability Improvement
(2016)
Lin, Y. C.
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Lin, J. C.
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Lin, Y.
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Wu, C. H.
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Chin, P. C.
GaN p-i-n photodetectors with an LT-GaN interlayer
(2008-04-01)
Lin, J. C.
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Su, Y. K.
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Chang, S. J.
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Lan, W. H.
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Huang, K. C.
Nitride-based p-i-n ultraviolet (UV) photodetectors with a low-temperature (LT) GaN interlayer were proposed and fabricated. Compared with a conventional GaN p-i-n photodetector, it was found that both the dark current and ideality factor of the p-i-n photodetector with an LT-GaN interlayer became larger whereas the UV-to-visible rejection ratio became smaller because of the poor crystal quality of the LT-GaN interlayer. However, the responsivity of the GaN p-i-n photocletector with an LT-GaN interlayer was larger than that of the conventional GaN p-i-n photocletector under a high reverse bias because of the carrier multiplication effect and/or internal gain that originated from the defect levels.
GaN-based light-emitting diodes prepared on vicinal sapphire substrates
(2007-02-01)
Lin, J. C.
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Su, Y. K.
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Chang, S. J.
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Lan, W. H.
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Huang, K. C.
Thin InGaN epitaxial layers and GaN-based light-emitting diodes (LEDs) on conventional and vicinal cut sapphire substrates are prepared. It is found that indium atoms are distributed much more uniformly in the samples prepared on vicinal cut sapphire substrates. It is also found that stronger electroluminescence intensity can be achieved without the band-filling effect of localised states from the LEDs with vicinal cut sapphire substrate. With 20 mA current injection, it is found that 44% electroluminescence intensity enhancement can be achieved by using the 1 degrees tilted sapphire substrate.
Growth and optical properties of high-density InN nanodots
(2010-10-15)
Ke, W. C.
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Lee, S. J.
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Kao, C. Y.
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Chen, W. K.
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Chou, W. C.
High density InN/GaN nanodots were grown by pulsed mode (PM) metal-organic chemical vapor deposition (MOCVD). InN nanodots density of up to similar to 5 x 10(10) cm(-2) at a growth temperature of 550 degrees C was achieved. The high diffusion activation energy of 2.65 eV due to high NH(3) flow rate generated more reactive nitrogen adatoms on the growth surface, and is believed to be the main reason for the growth of high density InN nanodots. In addition, an anomalous temperature dependence of the PL peak energy was observed for high density InN nanodots. The high carrier concentration, due to high In vacancy (V(ln)) in the InN nanodots, thermally agitated to the conduction band. As the measurement temperature increased, the increase of Fermi energy resulted in blue-shifted PL peak energy. From the Arrhenius plot of integrated PL intensity, the thermal activation energy for the PM grown InN nanodots was estimated to be E(a)similar to 51 meV, indicating strong localization of carriers in the high density InN nanodots. (C) 2010 Elsevier B.V. All rights reserved.
High light output intensity of titanium dioxide textured light-emitting diodes
(2008-08-01)
Huang, K. C.
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Lan, W. H.
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Huang, K. F.
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Lin, J. C.
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Cheng, Y. C.
Higher light output intensity and wider polar radiation pattern of InGaN/GaN multiple quantum well (MQW) light-emitting diodes (LEDs) with a different nanoscale titanium dioxide (TiO2) textured densities film have been observed. The light output power values and external quantum efficiency of the conventional LEDs at an injection current of 20 mA are 6.34 mW and 11.7%, respectively. The light output power values and external quantum efficiency of the nanoscaled TiO2 textured LEDs at an injection current of 20 mA are 7.55 mW and 14%, respectively. The light output intensity and power values of the nanoscaled TiO2 textured LEDs is approximately 65% and 20% higher than that of the conventional LEDs, respectively. (C) 2008 Elsevier Ltd. All rights reserved.
High responsivity of GaN p-i-n photodiode by using low-temperature interlayer
(2007-10-22)
Lin, J. C.
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Su, Y. K.
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Chang, S. J.
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Lan, W. H.
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Huang, K. C.
Gallium nitride p-i-n ultraviolet photodiodes with low- temperature (LT)- GaN interlayer have been fabricated. It was found that the dark current of photodiode with LT- GaN interlayer is as small as 143 pA at 5 V reverse bias. It was also found that the responsivity of the photodiode with LT- GaN interlayer can be enhanced at a small electric field (similar to 0.4 MV/cm) due to the carrier multiplication effect. The UV photocurrent gain of 13 and large ionization coefficient (alpha = 3.1 X 10(5) cm(-1)) were also observed in the detector with LT- GaN interlayer. Furthermore, we can achieve a large peak responsivity of 2.27 A/W from the photodiode with LT- GaN interlayer. (C) 2007 American Institute of Physics.
Improved external quantum efficiency of GaN p-i-n photodiodes with a TiO2 roughened surface
(2008-01-01)
Lin, J. C.
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Su, Y. K.
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Chang, S. J.
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Lan, W. H.
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Huang, K. C.
Gallium nitride p-i-n ultraviolet photodiodes (PDs) with a titanium dioxide (TiO2) nano-particles roughened surface have been fabricated. It was found that the responsivity and external quantum efficiency can be improved 60% on the surface roughened PDs. It was also found that light absorption can be enhanced from various incident angles by the TiO2 roughened surface. Furthermore, the high detectivity of 9.2 x 10(1.3) cm.Hz(1/2).W-1 can be achieved from the PD with a rough surface.
In0.11Ga0.89N-based p-i-n photodetector
(2009)
Su, Y. K.
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Lee, H. C.
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Lin, J. C.
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Huang, K. C.
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Lin, W. J.
The InGaN photodetector with a In composition of i-In0.11Ga0.89N active layer have been fabricated by MOCVD system. From the photoluminescence measurement, the FWHM of InGaN epitaxial layer was only 13.8 nm. The strong luminescence peak was located at wavelength of 399 nm. We also found that the FWHM of X-ray diffraction of GaN and InGan layer were 218 and 350 arcsec, respectively. Clear photo-responses are also observed in InGaN photodetector with 11% content at responsivity measurement. The cut-off range of spectral responsivity was occurred at 400 nm. The highest spectral responsivity of photodetector was 0.206 A/W at wavelength of 380 nm. The rejection ratio was approached to 103. The external quantum efficiency was about 67%. The current density-voltage (J-V) characteristic of i-InGaN p-i-n photodetector was measured. The dark and photo current density were 1.77x10(-4) A/cm(2) and 4.5x10(-2) A/cm(2) when biased at -3 V, respectively. At photovoltaic characteristics, the V-oc and J(sc) of the i-InGaN photodetector are 1.63 V and 3.1x10(-2) A/cm(2), respectively. The fill factor of i-InGaN p-i-n photodetector was about 37%. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Levosimendan shortens action potential duration, decreases alternans threshold and prevents ventricular arrhythmia during therapeutic hypothermia in isolated rabbit hearts
(2019-10-01)
Hsieh, Y. C.
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Li, C. H.
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Liao, Y. C.
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Lin, J. C.
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Weng, C. J.
Low dark current GaN p-i-n photodetectors with a low-temperature AIN interlayer
(2008-07-01)
Lin, J. C.
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Su, Y. K.
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Chang, S. J.
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Lan, W. H.
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Chen, W. R.
GaN p-i-n ultraviolet (UV) photodetectors (PDs) with a low-temperature (LT)-AIN interlayer were proposed and fabricated. It was found that the dark current of such detectors is as small as 28pA even at a high reverse bias of 40 V. Although the high potential barrier at the AIN-GaN interface would slightly reduce the responsivity of PD under low reverse biases, the high UV-to-visible rejection ratio of the PD with an LT-AIN interlayer could be achieved under high reverse biases due to its very low dark current. The rejection ratio of the PD with the LT-AIN interlayer is as large as 735 at the reverse bias of 40 V.
Middleware based inpatient healthcare information system
(2007)
Hsieh, S. H.
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Hsieh, S. L.
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Weng, Y. C.
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Yang, T. H.
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Lai, Feipei
The paper presents a multi-tier, integrated, distributed Inpatient Healthcare Information System based on Service Oriented Architecture (SOA) NET environment in National Taiwan University Hospital (NTUH). The architecture and outcomes of the newly developed Inpatient Information System (IIS) platform are discussed in details. We also present mechanisms of integration as well as interoperability among the components and multi-database in IIS via Health Level Seven (HL7) Middleware layer. The preliminary performance of the current operating IIS is evaluated and analyzed to verify the efficiency and effectiveness of the architecture we designed.