Browsing by Author "Huang, Yu-Ching"

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A Latchup-Immune and Robust SCR Device for ESD Protection in 0.25-mu m 5-V CMOS Process
(2013-05-01)
Huang, Yu-Ching
;
Ker, Ming-Dou
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
Based on good electrostatic discharge (ESD) robustness, silicon-controlled rectifier (SCR) device is used for on-chip ESD protection. The major concern of SCR is the latch-up issue, because of its low holding voltage. Previous papers tried to design latchup-immune SCR devices; however, those devices would cause lower ESD robustness. In this letter, a new latchup-immune and robust SCR device for ESD protection is proposed and verified in a 0.25-mu m 5-V CMOS process. Through inserting one additional parasitic bipolar junction transistor into SCR device structure, this new proposed SCR can increase the holding voltage without causing degradation on its ESD robustness.
Application of m-CNTs/NaClO4/Ppy to a fast response, room working temperature ethanol sensor
(2008-08-28)
Wu, Ren-Jang
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Huang, Yu-Ching
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Yu, Ming-Ru
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Lin, Tzu Hsuan
;
Hung, Shih-Lin
A new blended material, m-CNTs/NaClO4/Ppy, was developed as a gas sensor to detect ethanol concentrations at room temperature. The sensing material polypyrrole (Ppy) was synthesized in situ by UV-photo-polymerization. The multiwall carbon nanotubes (m-CNTs) added enhanced the short-term repeatability of the Ppy-sensing material. The relative resistance variation (R-ethanol/R-air) of mCNTs/NaClO4/Ppy was 1.193 when exposed to ethanol of 30,000 ppm. The sensor response and recovery times (both 20s) were very short to this concentration. An unstable baseline of the sensor was explained by theoretical calculation of molecular dynamics made for ethanol adsorption on polypyrrole, which revealed formation of a new bond, N-H center dot center dot center dot O. Adsorption energy decreased with increasing the number of ethanol molecules adsorbed and was 0.8 kcal/mol at eight adsorbed molecules. Sensor responses of three different Ppy samples were measured to ethanol concentrations of 18,000-40,000 ppm. (C) 2008 Elsevier B.V. All rights reserved.
Cofacial Versus Coplanar Arrangement in Centrosymmetric Packing Dimers of Dipolar Small Molecules: Structural Effects on the Crystallization Behaviors and Optoelectronic Characteristics
(2016-07-20)
Chou, Shu-Hua
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Kang, Hao-Wei
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Chang, Shu-Ting
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Wu, Kuan-Yi
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Bazan, Guillermo C.
Two D-pi-A-A molecules (MIDTP and TIDTP) composed of an electron-rich ditolylamino group (D) and an electron-deficient 5-dicyanovinylenylpyrimidine (A-A) fragment bridged together with indeno[1,2-b]thiophene (IDT) were synthesized. These molecules provide an opportunity to examine in-depth the impact of side-chain variations (methyl vs p-tolyl) on the crystallization behaviors, solid-state morphology, physical properties, and optoelectronic characteristics relevant for practical applications. X-ray analyses on single-crystal structures indicate that methyl-substituted MIDTP forms coplanar antiparallel dimers via C-H center dot center dot center dot S interactions and organizes into an ordered slip-staircase arrays. In contrast, p-tolyl-bearing TIDTP shows cofacial centrosymmetric dimers via pi-pi interactions and packs into a less-ordered layered structures. The X-ray diffraction analyses upon thermal treatment are consistent with a superior crystallinity of MIDTP, as compared to that of TIDTP. This difference indicates a greater propensity to organization by introduction of the smaller methyl group versus the bulkier p-tolyl group. The increased propensity for order by MIDTP facilitates the crystallization of MIDTP in both solution-processed and vacuum-deposited thin films. MIDTP forms solution-processed single-crystal arrays that deliver OFET hole mobility of 6.56 x 10(-4) cm(2) V-1 s(-1), whereas TIDTP only forms amorhpous films that gave lower hole mobility of 1.34 x 10(-5) cm(2) V-1 s(-1). MIDTP and TIDTP were utilized to serve as donors together with C-70 as acceptor in the fabrication of small-molecule organic solar cells (SMOSCs) with planar heterojunction (PHJ) or planar-mixed heterojunction (PMHJ) device architectures. OPV devices based on higher crystalline MIDTP delivered power conversion efficiencies (PCEs) of 2.5% and 4.3% for PHJ and PMHJ device, respectively, which are higher than those of TIDTP-based cells. The improved PCEs of MIDTP-based devices are attributed to better hole-transport character.
Inhibition of p38 MAPK-dependent MutS homologue-2 (MSH2) expression by metformin enhances gefitinib-induced cytotoxicity in human squamous lung cancer cells
(2013-12-01)
Ko, Jen-Chung
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Chiu, Hsien-Chun
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Wo, Ting-Yu
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Huang, Yi-Jhen
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Tseng, Sheng-Chieh
Objectives: Gefitinib, a quinazoline-derived tyrosine kinase inhibitor, has anti-tumor activity in vivo and in vitro. Human MutS homologue-2 (MSH2) plays a central role in promoting genetic stability by correcting DNA replication errors. The present study investigated the effects of p38 mitogen-activated protein kinase (MAPK) signal on gefitinib-induced MSH2 expression in two human non-small cell lung squamous cancer cell lines. Materials and methods: After the gefitinib treatment, the expressions of MSH2 mRNA were determined by real-time PCR and RT-PCR analysis. Protein levels of MSH2, phospho-MKK3/6, phospho-p38 MAPK were determined by Western blot analysis. We used specific MSH2, and p38 MAPK small interfering RNA to examine the role of p38 MAPK-MSH2 signal in regulating the chemosensitivity of gefitinib. Cell viability was assessed by MTS assay, trypan blue exclusion, and colony-forming ability assay. Results: Exposure of gefitinib increased MSH2 protein and mRNA levels, which was accompanied by MKK3/6-p38 MAPK activation in H520 and H1703 cells. Moreover, blocking p38 MAPK activation by SB202190 significantly decreased gefitinib-induced MSH2 expression by increasing mRNA and protein instability. In contrast, enhancing p38 activation using constitutively active MKK6 (MKK6E) increased MSH2 protein and mRNA levels. Specific inhibition of MSH2 expression by siRNA enhanced gefitinib-induced cytotoxicity. Metformin, an anti-diabetic drug, might reduce cancer risk. In human lung squamous cancer cells, metformin decreased gefitinib-induced MSH2 expression and augmented the cytotoxic effect and growth inhibition by gefitinib. Transient expression of MKK6E or HA-p38 MAPK vector could abrogate metformin and gefitinib-induced synergistic cytotoxic effect in H520 and H1703 cells. Conclusion: Together, down-regulation of MSH2 expression can be a possible strategy to enhance the sensitivity of gefitinib to human lung squamous cancer cells. (C) 2013 Elsevier Ireland Ltd. All rights reserved.
LMMSE-Based Sidelink Channel Estimation for LTE Communication Systems
(2019-01-01)
Huang, Yu-Ching
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Lin, David W.
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
The 3GPP LTE series of standards have made provisions for device-to-device (D2D) and vehicle-to-everything (V2X) communication in recent releases. The interface accommodating such communication is termed the sidelink (SL), which reuses some physical layer specifications originally defined for the uplink, such as single-carrier frequency-division multiple access (SC-FDMA), with some modifications. One modification is the use of doubly dense demodulation reference signals (DMRS) in the V2X setting to assist channel estimation. An SC-FDMA channel estimator typically starts with a least-squares (LS) estimation of the channel frequency response (CFR) at the DMRS. It then obtains CFR estimates for the data subcarriers by some time-frequency filtering. This work considers SL channel estimation techniques. The proposed method employs a novel linear minimum mean-square error (LMMSE) filtering mechanism in the frequency domain to reduce the noise in the LS CFR estimates and then, depending on the DMRS density, uses particularly designed LMMSE filtering or polynomial interpolation in the time domain to obtain the desired CFR estimates for the data subcarriers. Simulation results show that the method can yield superior performance over a wide range of channel conditions.
Local CDM ESD Protection Circuits for Cross-Power Domains in 3D IC Applications
(2014-06-01)
Chen, Shih-Hung
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Linten, Dimitri
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Scholz, Mirko
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Huang, Yu-Ching
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Hellings, Geert
CDM ESD events can be a potential threat to SoC designs or heterogeneous 3D ICs with multiple power domains. Inter-layer ( or interface) circuits may need a local CDM ESD clamp that can prevent the unexpected failure under CDM ESD stress. In this letter, two local CDM ESD clamp circuits are proposed. They show better clamping efficiency under 2-ns vfTLP stress.
New sensing technology for detection of the common inhalational anesthetic agent sevoflurane using conducting polypyrrole films
(2007-10-01)
Wu, Ren-Jang
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Huang, Yu-Ching
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Chavali, Murthy
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Lin, Tzu Hsuan
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Hung, Shih-Lin
A new type of gas sensor to measure resistance was developed to detect sevoflurane concentrations at room temperature. The measured FTIR spectrum of sevoflurane vapor was given. The sensing material polypyrrole was synthesized in situ by UV-photopolymerization. The relative resistance variation was 3.9 for a sevoflurane concentration of 1.2%. The sensor response time (60 s) and recovery time (20 s) were very short. Molecular dynamic calculations made for sevoflurane adsorption on polypyrrole revealed formation of a new bond, N-H-F. The bond length was predicted to be in the range of 0.2-0.4 nm. The bond energy was about 7.2 kcal/mol. Sensor responses to the concentrations 0. 1-10% were 1.57-5.9, respectively. (C) 2007 Elsevier B.V. All rights reserved.
Pemetrexed downregulates ERCC1 expression and enhances cytotoxicity effected by resveratrol in human nonsmall cell lung cancer cells
(2013-12-01)
Chen, Ruey-Shyang
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Ko, Jen-Chung
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Chiu, Hsien-Chun
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Wo, Ting-Yu
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Huang, Yi-Jhen
The multitargeted antifolate pemetrexed has demonstrated certain clinical activities against nonsmall cell lung cancer (NSCLC). Resveratrol (3,5,4-trihydroxy-trans-stilbene) is a polyphenol found in grapes and other plants and has great potential as a preventative and therapeutic agent due to its anticarcinogenic activity. The efficacy of adding resveratrol to pemetrexed to prolong the survival of patients with NSCLC still remains unclear. The excision repair cross-complementation 1 (ERCC1) is a DNA repair gene coding 5' endonuclease in nucleotide excision repair and is overexpressed in chemo- or radioresistant carcinomas. In this study, resveratrol (10-50 mu M) inhibited cell survival in two NSCLC cells, H520 and H1975. Treatment with resveratrol increased ERCC1 messenger RNA and protein levels in a MKK3/6-p38 MAPK signal activation-dependent manner. Furthermore, blocking p38 MAPK activation by SB202190 or knocking down ERCC1 expression by transfection with small interfering RNA of ERCC1 enhanced the cytotoxicity of resveratrol. Combining resveratrol with pemetrexed resulted in a synergistic cytotoxic effect, accompanied with the reduction of phospho-p38 MAPK and ERCC1 protein levels, and a DNA repair capacity. Expression of constitutively active MKK6 (MKK6E) or HA-p38 MAPK vectors significantly rescued the decreased p38 MAPK activity, and restored ERCC1 protein levels and cell survival in resveratrol and pemetrexed cotreated NSCLC cells. In this study, for the first time, we have demonstrated the synergistic effect of combined treatment with resveratrol and pemetrexed in human NSCLC cells through downregulation of the MKK3/6-p38 MAPK-ERCC1 signal, suggesting a potential benefit of combining resveratrol and pemetrexed to treat lung cancer in the future.
Performance Characterization of Dye-Sensitized Photovoltaics under Indoor Lighting
(2017-04-20)
Chen, Chia-Yuan
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Jian, Zih-Hong
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Huang, Shih-Han
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Lee, Kun-Mu
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Kao, Ming-Hsuan
Indoor utilization of emerging photovoltaics is promising; however, efficiency characterization under room lighting is challenging. We report the first round-robin interlaboratory study of performance measurement for dye-sensitized photovoltaics (cells and mini-modules) and one silicon solar cell under a fluorescent dim light. Among 15 research groups, the relative deviation in power conversion efficiency (PCE) of the samples reaches an unprecedented 152%. On the basis of the comprehensive results, the gap between photometry and radiometry measurements and the response of devices to the dim illumination are identified as critical obstacles to the correct PCE. Therefore, we use an illuminometer as a prime standard with a spectroradiometer to quantify the intensity of indoor lighting and adopt the reverse-biased current voltage (I-V) characteristics as an indicator to qualify the I-V sampling time for dye-sensitized photovoltaics. The recommendations can brighten the prospects of emerging photovoltaics for indoor applications.
Quantitative Characterization and Mechanism of Formation of Multilength-scale Bulk Heterojunction Structures in Highly Efficient Solution-Processed Small-Molecule Organic Solar Cells
(2015-07-23)
Huang, Yu-Ching
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Tsao, Cheng-Si
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Huang, Tzu-Yen
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Cha, Hou-Chin
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Patra, Dhananjaya
In this study we used simultaneous grazing-incidence small- and wide-angle X-ray scattering (GISAXS and GIWAXS, respectively) to probe the multilength-scale structures of thin active layers comprising the linear A-D-A-type pi-conjugated donor molecule TBDTCNR and the fullerene acceptor molecule PC61BM for use in solution-processed small-molecule-based organic solar cells (SMOSCs). We found that the pseudo-two-dimensional fractal-like networks in the bulk heterojunction (BHJ) structure were determined by mutual interactions between the small-molecule (SM) crystallites and the nanoscale PC61BM clusters during their formation and phase separation, and deduced quantitatively, at multiple length scales, the BHJ structures comprising these SM crystallites and PC61BM clusters. We also conducted in situ GIWAXS measurements to study the temporal behavior and kinetics of SM crystallization from solution to the solid film state. Our GISAXS/GIWAXS study revealed that the multilength-scale BHJ structures in the thin films could be tuned effectively by varying the amount of incorporated PC61BM and the annealing temperature. This study provides fundamental information relating to the mechanism of formation of hierarchical BHJ structures through relatively rapid crystallization of a highly crystalline SM, as well as the relationships among the hierarchical structure, the photovoltaic performance, and the mechanism of formation, thereby allowing greater control over BHJ structures in SMOSCs with optimized fabrication and performance.
Self-Protected LDMOS Output Device with Embedded SCR to Improve ESD Robustness in 0.25-mu m 60-V BCD Process
(2013)
Huang, Yu-Ching
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Dai, Chia-Tsen
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Ker, Ming-Dou
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
For high-voltage output driver, the lateral DMOS (LDMOS) is often used for both output function operation and self-protection against electrostatic discharge (ESD) events. In this work, a new structure of LDMOS output device with embedded SCR has been proposed and verified in a 0.25-mu m 60-V BCD process. This new structure, with additional p(+) and n(+) implantation regions added between the drain contact and poly-gate of LDMOS, can keep it stably in the high-current holding region after snapback. By using this structure, the LDMOS can provide high enough self-protected ESD robustness for applications in the high-voltage output drivers.