Browsing by Author "Chen, Yi-Ju"

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A Numerical Study of Si-TMD Contact with n/p Type Operation and Interface Barrier Reduction for Sub-5 nm Monolayer MoS2 FET
(2016-01-01)
Tang, Ying-Tsan
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Li, Kai-Shin
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Li, Lain-Jong
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Li, Ming-Yang
;
Lin, Chang-Hsien
An atomic-scale numerical study of Si contact with transition metal dichalcogenides (TMD) semiconductor materials is proposed by first-principles simulation for the first time. The monolayer MoS2 channel can be operated as both of n- and p-type FET by properly doping Si S/D to adjust the TMD channel potential. The gradient MoSx junction of dichalcogenide vacancies enables Si-MoS2 contact resistance lower than 100 Omega-mu m for interface Schottky barrier height reduction. The compact Si-MoS2 interface study can potentially provide monolayer TMD contact design guideline for the sub-5 nm TMD FET fabrication technology.
An enzymatic approach to configurationally rare trans-androsteronyl--glucoside and Its potential anticancerapplication
(2017-01)
Chou, Feng-Pai
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Tsai, Chia-Tse
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Chiou, Ya-Sheng
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Chen, Yi-Ju
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Li, Meng-Erh
Enzymatic glycosylation of sterols/steroids with glycosyltransferase HP0421 shows protein plasticity on generation of configurationally rare steryl--glucosides. Investigation of trans-androsteronyl--glucoside on tamoxifen-treated MCF-7 breast cancer cells shows dose-dependent depression of cell viability and enhanced drug effectiveness, illustrating a new avenue for the production of novel steryl--glucosides with useful biological activities.
Bandgap engineering of Si1-xGex epitaxial tunnel layer for tunnel FETs
(2018-08-01)
Chen, Yi-Ju
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Tsui, Bing-Yue
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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 effects of the Si-1-xGe(x) epitaxial tunnel layer (ETL) scheme and ETL thickness on the ON-state current (l(ON)) of Si-1_Ge-x(x) ETL tunnel field-effect transistors (TFETs) are thoroughly studied in this work. Compared with using pure Ge as the ETL, implementing Si1-xGex with linearly changing Ge content degrades l(ON) markedly, whereas using Si1-xGex with stepwise changing Ge content degrades l(ON) slightly. Although changing the ETL material from Ge to Si1-xGex leads to l(ON) reduction, for practical implementation, it is anticipated that a better subthreshold swing (SS) can be obtained by ETL crystal quality improvement. The best Si1-xGex ETL scheme for application in complementary Si1-xGex ETL TFETs is 4-nm-thick Si1-xGex with stepwise decreasing bandgap (E-g).( )It is believed that this structure is more promising for implementation. (C) 2018 The Japan Society of Applied Physics.
Crystal Structure and Mutational Analysis of Aminoacylhistidine Dipeptidase from Vibrio alginolyticus Reveal a New Architecture of M20 Metallopeptidases
(2010-12-01)
Chang, Chin-Yuan
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Hsieh, Yin-Cheng
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Wang, Ting-Yi
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Chen, Yi-Chin
;
Wang, Yu-Kuo
Aminoacylhistidine dipeptidases (PepD, EC 3.4.13.3) belong to the family of M20 metallopeptidases from the metallopeptidase H clan that catalyze a broad range of dipeptide and tripeptide substrates, including L-carnosine and L-homocarnosine. Homocarnosine has been suggested as a precursor for the neurotransmitter gamma-aminobutyric acid (GABA) and may mediate the antiseizure effects of GABAergic therapies. Here, we report the crystal structure of PepD from Vibrio alginolyticus and the results of mutational analysis of substrate-binding residues in the C-terminal as well as substrate specificity of the PepD catalytic domain-alone truncated protein PepD(CAT). The structure of PepD was found to exist as a homodimer, in which each monomer comprises a catalytic domain containing two zinc ions at the active site center for its hydrolytic function and a lid domain utilizing hydrogen bonds between helices to form the dimer interface. Although the PepD is structurally similar to PepV, which exists as a monomer, putative substrate-binding residues reside in different topological regions of the polypeptide chain. In addition, the lid domain of the PepD contains an "extra" domain not observed in related M20 family metallopeptidases with a dimeric structure. Mutational assays confirmed both the putative di-zinc allocations and the architecture of substrate recognition. In addition, the catalytic domain-alone truncated PepD(CAT) exhibited substrate specificity to L-homocarnosine compared with that of the wild-type PepD, indicating a potential value in applications of PepD(CAT) for GABAergic therapies or neuroprotection.
Crystal Structure and Mutational Analysis of Aminoacylhistidine Dipeptidase from Vibrio alginolyticus Reveal a New Architecture of M20 Metallopeptidases
(2010-12-01)
Chang, Chin-Yuan
;
Hsieh, Yin-Cheng
;
Wang, Ting-Yi
;
Chen, Yi-Chin
;
Wang, Yu-Kuo
Aminoacylhistidine dipeptidases (PepD, EC 3.4.13.3) belong to the family of M20 metallopeptidases from the metallopeptidase H clan that catalyze a broad range of dipeptide and tripeptide substrates, including L-carnosine and L-homocarnosine. Homocarnosine has been suggested as a precursor for the neurotransmitter gamma-aminobutyric acid (GABA) and may mediate the antiseizure effects of GABAergic therapies. Here, we report the crystal structure of PepD from Vibrio alginolyticus and the results of mutational analysis of substrate-binding residues in the C-terminal as well as substrate specificity of the PepD catalytic domain-alone truncated protein PepD(CAT). The structure of PepD was found to exist as a homodimer, in which each monomer comprises a catalytic domain containing two zinc ions at the active site center for its hydrolytic function and a lid domain utilizing hydrogen bonds between helices to form the dimer interface. Although the PepD is structurally similar to PepV, which exists as a monomer, putative substrate-binding residues reside in different topological regions of the polypeptide chain. In addition, the lid domain of the PepD contains an "extra" domain not observed in related M20 family metallopeptidases with a dimeric structure. Mutational assays confirmed both the putative di-zinc allocations and the architecture of substrate recognition. In addition, the catalytic domain-alone truncated PepD(CAT) exhibited substrate specificity to L-homocarnosine compared with that of the wild-type PepD, indicating a potential value in applications of PepD(CAT) for GABAergic therapies or neuroprotection.
dbPTM 3.0: an informative resource for investigating substrate site specificity and functional association of protein post-translational modifications
(2013-01-01)
Lu, Cheng-Tsung
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Huang, Kai-Yao
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Su, Min-Gang
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Lee, Tzong-Yi
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Bretana, Neil Arvin
Protein modification is an extremely important post-translational regulation that adjusts the physical and chemical properties, conformation, stability and activity of a protein; thus altering protein function. Due to the high throughput of mass spectrometry (MS)-based methods in identifying site-specific post-translational modifications (PTMs), dbPTM (http://dbPTM.mbc.nctu.edu.tw/) is updated to integrate experimental PTMs obtained from public resources as well as manually curated MS/MS peptides associated with PTMs from research articles. Version 3.0 of dbPTM aims to be an informative resource for investigating the substrate specificity of PTM sites and functional association of PTMs between substrates and their interacting proteins. In order to investigate the substrate specificity for modification sites, a newly developed statistical method has been applied to identify the significant substrate motifs for each type of PTMs containing sufficient experimental data. According to the data statistics in dbPTM, > 60% of PTM sites are located in the functional domains of proteins. It is known that most PTMs can create binding sites for specific protein-interaction domains that work together for cellular function. Thus, this update integrates protein-protein interaction and domain-domain interaction to determine the functional association of PTM sites located in protein-interacting domains. Additionally, the information of structural topologies on transmembrane (TM) proteins is integrated in dbPTM in order to delineate the structural correlation between the reported PTM sites and TM topologies. To facilitate the investigation of PTMs on TM proteins, the PTM substrate sites and the structural topology are graphically represented. Also, literature information related to PTMs, orthologous conservations and substrate motifs of PTMs are also provided in the resource. Finally, this version features an improved web interface to facilitate convenient access to the resource.
dbSNO: a database of cysteine S-nitrosylation
(2012-09-01)
Lee, Tzong-Yi
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Chen, Yi-Ju
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Lu, Cheng-Tsung
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Ching, Wei-Chieh
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Teng, Yu-Chuan
SUMMARY: S-nitrosylation (SNO), a selective and reversible protein post-translational modification that involves the covalent attachment of nitric oxide (NO) to the sulfur atom of cysteine, critically regulates protein activity, localization and stability. Due to its importance in regulating protein functions and cell signaling, a mass spectrometry-based proteomics method rapidly evolved to increase the dataset of experimentally determined SNO sites. However, there is currently no database dedicated to the integration of all experimentally verified S-nitrosylation sites with their structural or functional information. Thus, the dbSNO database is created to integrate all available datasets and to provide their structural analysis. Up to April 15, 2012, the dbSNO has manually accumulated >3000 experimentally verified S-nitrosylated peptides from 219 research articles using a text mining approach. To solve the heterogeneity among the data collected from different sources, the sequence identity of these reported S-nitrosylated peptides are mapped to the UniProtKB protein entries. To delineate the structural correlation and consensus motif of these SNO sites, the dbSNO database also provides structural and functional analyses, including the motifs of substrate sites, solvent accessibility, protein secondary and tertiary structures, protein domains and gene ontology.
Degradation Mechanism of Ge N+-P Shallow Junction With Thin GeSn Surface Layer
(2020-03-01)
Tsui, Bing-Yue
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Liao, Hsiu-Hsien
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Chen, Yi-Ju
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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
In this article, the degradation mechanism of the Ge N+-P junctions with a thin GeSn surface layer is investigated, aiming for source/drain (S/D) application in emerging field-effect transistors. GeSn is a promising channel material with high carrier mobility, which can offer a better performance of the field-effect transistors. By performing thermal annealing at different temperatures, the reverse-biased leakage current increases apparently when annealing temperature exceeds 550 degrees C. X-ray diffraction (XRD) analysis indicates most Sn atoms escape from lattice sites while secondary-ion mass spectroscopy (SIMS) analysis indicates enhanced Sn diffusion in Ge bulk after ion implantation. Therefore, a degradation model considering Sn-defects interaction is proposed to explain the degradation of junction leakage current and possible solution is proposed.
Design of a 0.5V 1.68mW Nose-on-a-Chip for Rapid Screen of Chronic Obstructive Pulmonary Disease
(2016-01-01)
Chou, Ting-I
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Chiu, Shih-Wen
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Chang, Kwuang-Han
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Chen, Yi-Ju
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Tang, Chen-Ting
Chronic obstructive pulmonary disease (COPD) still lacks a rapid diagnosis strategy. In this paper, we propose a low-power nose-on-a-chip for rapid COPD screening. This chip is designed for implementation in a personal handheld device that detects patient breath for COPD diagnosis. The chip has 36 on-chip sensors, a 36-channel adaptive interface with an integrated programmable amplifier, a four-channel frequency readout interface, one on-chip temperature sensor, a two-channel successive approximation analog-to-digital converter, a scalable learning kernel cluster, and a reduced instruction set computing core with low-voltage static random-access memory. This chip is fabricated in 90 nm CMOS and consumes 1.68 mW at 0.5 V. In simulation, the system distinguished between undiseased and diseased patients with 90.82% accuracy for a set of diseases including COPD and asthma and exhibited 92.31% accuracy for identifying patients with COPD or asthma. The system classified severity levels of COPD under four labels (normal, mild, moderate, and severe) with 92.00% accuracy. Accordingly, this work provides a promising solution for the unmet medical need of rapid COPD screening.
Designable Spectrometer-Free Index Sensing Using Plasmonic Doppler Gratings
(2019-08-06)
Lin, Fan-Cheng
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See, Kel-Meng
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Ouyang, Lei
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Huang, You-Xin
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Chen, Yi-Ju
Typical nanoparticle-based plasmonic index sensors detect the spectral shift of localized surface plasmon resonance (LSPR) upon the change of the environmental index. Therefore, they require broadband illumination and spectrometers. The sensitivity and flexibility of nanoparticle-based index sensors are usually limited because LSPR peaks are usually broad and the spectral position cannot be freely designed. Here, we present a fully designable index sensing platform using plasmonic Doppler gratings (PDGs), which provide broadband and azimuthal angle dependent grating periodicity. Different from LSPR sensors, PDG index sensors are based on the momentum matching between photons and surface plasmons via the lattice momentum of the grating. Therefore, the index change is translated into the variation of the in-plane azimuthal angle for photon-to-plasmon coupling, which manifests as directly observable dark bands in the reflection image. The PDG can be freely designed to optimally match the range of index variation for specific applications. In this work, we demonstrate PDG index sensors for large (n = 1.00-1.52) and small index variations (n = 1.3330-1.3650). The tiny and nonlinear index change of the water-ethanol mixture has been clearly observed and accurately quantified. Since the PDG is a dispersive device, it enables on-site and single-color index sensing without a spectrometer and provides a promising spectroscopic platform for on-chip analytical applications.
Detachment and transfer of ordered TiO(2) nanotube arrays for front-illuminated dye-sensitized solar cells
(2011-09-01)
Li, Lu-Lin
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Chen, Yi-Ju
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Wu, Hui-Ping
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Wang, Niann S.
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Diau, Eric Wei-Guang
We report a method of detachment and transfer of one-dimensional TiO(2) nanotube (NT) arrays to fabricate dye-sensitized solar cells (DSSCs) with illumination from the front side. The ordered NT arrays (tube length 20 mm) were detached from the NT-Ti substrate, as annealed, by means of a second anodization at 20 V for 4 h and then transferred, inverted, onto a transparent substrate of conducting oxide (TCO) with an interface of TiO(2) nanoparticles of thickness similar to 2 mu m. Dry etching of the NT surface in a highly dense plasma reactor under BCl(3)/Cl(2) for 90 s opened previously closed ends of the tubes. The inverted (bottom-up) NT-TCO substrate was fabricated into a DSSC device that shows a cell performance (eta = 6.24%) significantly improved over those of a front-illuminated counterpart with an upright (face-up) structure (eta = 4.84%) and of a conventional back-illuminated device (eta = 4.61%). Electrochemical impedance spectra (EIS) of the devices under one-sun irradiation were measured to rationalize the cell performances that are consistent with the corresponding interfacial impedances between the NT arrays and the electrode for collection of electrons.
Detachment and transfer of ordered TiO2 nanotube arrays for front-illuminated dye-sensitized solar cells
(2011-09-01)
Li, Lu-Lin
;
Chen, Yi-Ju
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Wu, Hui-Ping
;
Wang, Niann S.
;
Diau, Eric Wei-Guang
We report a method of detachment and transfer of one-dimensional TiO2 nanotube (NT) arrays to fabricate dye-sensitized solar cells (DSSCs) with illumination from the front side. The ordered NT arrays (tube length 20 mm) were detached from the NT-Ti substrate, as annealed, by means of a second anodization at 20 V for 4 h and then transferred, inverted, onto a transparent substrate of conducting oxide (TCO) with an interface of TiO2 nanoparticles of thickness similar to 2 mu m. Dry etching of the NT surface in a highly dense plasma reactor under BCl3/Cl-2 for 90 s opened previously closed ends of the tubes. The inverted (bottom-up) NT-TCO substrate was fabricated into a DSSC device that shows a cell performance (eta = 6.24%) significantly improved over those of a front-illuminated counterpart with an upright (face-up) structure (eta = 4.84%) and of a conventional back-illuminated device (eta = 4.61%). Electrochemical impedance spectra (EIS) of the devices under one-sun irradiation were measured to rationalize the cell performances that are consistent with the corresponding interfacial impedances between the NT arrays and the electrode for collection of electrons.
Effects of Vanadium Incorporation on the Electron Schottky Barrier Height Reduction of NiGe/Ge
(2017-01-01)
Chen, Yi-Ju
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Tsui, Bing-Yue
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Effects of vanadium incorporation on the electron Schottky barrier height reduction of NiGe/Ge is investigated. The best results achieved in this work is 70 meV electron Schottky barrier height reduction by depositing vanadium layer followed by Ar ion bombardment.
Estimating the Detection Stability of a Si Nanowire Sensor Using an Additional Charging Electrode
(2013)
Chen, Min-Cheng
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Chen, Hsiao-Chien
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Lee, Ta-Hsien
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Lin, Yu-Hsien
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Shih, Jyun-Hung
This paper proposes a sensing stability estimation method that involves using an additional forcing electrode to simulate the surface charge coupling effect for bottom gate nanowire sensors. The alteration of the Si nanowire can be observed by using the charging electrode without any complex surface treatment and micro-channel setup. The nanowire sensor has a distinct charge-sensitive slope (V-th shift > 60 mV/10(-16)C) with a wire-width scaling of 35 nm. The proposed estimation technique simplifies the charge sensing operation.
High Performance Poly Si Junctionless Transistors with Sub-5nm Conformally Doped Layers by Molecular Monolayer Doping and Microwave Incorporating CO2 Laser Annealing for 3D Stacked ICs Applications
(2015)
Lee, Yao-Jen
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Cho, Ta-Chun
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Sung, Po-Jung
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Kao, Kuo-Hsing
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Hsueh, Fu-Kuo
A junctionless (JL) fin thin film transistor (FinTFT) with a novel shell doping profile (SDP) formed by a damage-free conformal molecular monolayer doping (MLD) method and a combination of microwave annealing (MWA) and CO2 laser spike annealing (COLSA) is demonstrated and studied. MWA drives in and partially activates the MLD dopants; the resultant SDP features an ultra-shallow depth (< 5nm) and an abrupt steepness (< 0.8 nm/dec). The dopant activation of the devices experienced MLD and MWA is further enhanced by the nonmelting COLSA without dopant diffusion, and which can also avoid fin deformation and recover surface defects left by fin patterning. Thanks to the enhanced dopant activation by COLSA, the SDP-FinTFTs overall exhibit better performance than the SDP-FinTFTs without COLSA and the conventional implanted (imp) FinTFTs in terms of subthreshold swing (S.S.), on-currents (I-on by 160% compared to the SDP-FinTFTs without COLSA) and on/off current ratio (I-on/I-off > 10(7)) for 3D stacked ICs applications. Our results reveal the potential of the proposed SDP formed by MLD, MWA and COLSA enabling a JLFinTFT showing excellent performance.
Hybrid Si/TMD 2D Electronic Double Channels Fabricated Using Solid CVD Few-Layer-MoS2 Stacking for V-th Matching and CMOS-Compatible 3DFETs
(2014)
Chen, Min-Cheng
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Lin, Chia-Yi
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Li, Kai-Hsin
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Li, Lain-Jong
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Chen, Chang-Hsiao
Stackable 3DFETs such as FinFET using hybrid Si/MoS 2 channels were developed using a fully CMOS-compatible process. Adding several molecular layers (3-16 layers) of the transition-metal dichalcogenide (TMD), MoS2 to Si fin and nanowire resulted in improved (+25%) I-on,I-n of the FinFET and nanowire FET (NWFET). The PFETs also operated effectively and the N/P device V-th are low and matched perfectly. The proposed heterogeneous Si/TMD 3DFETs can be useful in future electronics.
iTop-Q: an Intelligent Tool for Top-down Proteomics Quantitation Using DYAMOND Algorithm
(2017-12-19)
Chang, Hui-Yin
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Chen, Ching-Tai
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Ko, Chu-Ling
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Chen, Yi-Ju
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Chen, Yu-Ju
Top-down proteomics using liquid chromatogram coupled with mass spectrometry has been increasingly applied for analyzing intact proteins to study genetic variation, alternative splicing, and post-translational modifications (PTMs) of the proteins (proteoforms). However, only a few tools have been developed for charge state deconvolution, monoisotopic/average molecular weight determination and quantitation of proteoforms from LC-MS1 spectra. Though Decon2LS and MASH Suite Pro have been available to provide intraspectrum charge state deconvolution and quantitation, manual processing is still required to quantify proteoforms across multiple MS1 spectra. An automated tool for interspectrum quantitation is a pressing need. Thus, in this paper, we present a user-friendly tool, called iTop-Q (intelligent Top-down Proteomics Quantitation), that automatically performs large-scale proteoform quantitation based on interspectrum abundance in top-down proteomics. Instead of utilizing single spectrum for proteoform quantitation, iTop-Q constructs extracted ion chromatograms (XICs) of possible proteoform peaks across adjacent MS' spectra to calculate abundances for accurate quantitation. Notably, iTop-Q is implemented with a newly proposed algorithm, called DYAMOND, using dynamic programming for charge state deconvolution. In addition, iTop-Qperforms proteoform alignment to support quantitation analysis across replicates/samples. The performance evaluations on an in-house standard data set and a public large-scale yeast lysate data set show that iTop-Q achieves highly accurate quantitation, more consistent quantitation than using intraspectrum quantitation. Furthermore, the DYAMOND algorithm is suitable for high charge state deconvolution and can distinguish shared peaks in coeluting proteoforms. iTop-Qis publicly available for download at http://ms.iis.sinica.edu.tw/COmics/Software_iTop-Q.
MOS2 U-shape MOSFET with 10 nm Channel Length and Poly-Si Source/Drain Serving as Seed for Full Wafer CVD MOS2 Availability
(2016)
Li, Kai-Shin
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Wu, Bo-Wei
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Li, Lain-Jong
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Li, Ming-Yang
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Cheng, Chia-Chin Kevin
A U-shape MOS2 pMOSFET with 10nm channel and poly-Si source/drain is demonstrated. The fabrication process is simple. Because the Si S/D serves as the nucleation seed for CVD MOS2 deposition, thin MOS2 is well deposited in the channel region any where over the fully scale oxide coated Si wafer. This is a big step forward toward a low cost multi-layer stacked TMD IC technology.
Negative-Capacitance FinFET Inverter, Ring Oscillator, SRAM Cell, and Ft
(2018-01-01)
Li, Kai-Shin
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Wei, Yun-Jie
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Chen, Yi-Ju
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Chiu, Wen-Cheng
;
Chen, Hsiu-Chih
In this work, we use thermal-ALD to prepare ferroelectric HfZrO2 (HZO) thin film with thickness from 3 to 7 nm for the NC-FinFET's gate stack. The subthreshold swing (SS) was as low as 5 mV/dec (SSmin) over 4 orders of I-D. Lower thermal budget process, CO2 far-infrared laser activation and 400 degrees C Ni silicide are employed in the 2-level metal backend integration for maintaining the orthorhombic phase in HZO thin film and minimizing the hysteresis in IV. NC-FinFET inverter has 77% higher voltage gain compared to FinFET-inverter employing HfO2 gate dielectric. NC-FinFET ring oscillator exhibit small speed and power advantages over FinFET oscillator. For the first time, NC-FET cut-off frequency (F-t) frequency is measured, 23.1 GHz or 23% higher than the control FET Ft. NC-FinFET SRAM was observed to exhibit large noise margin.
Proteogenomics of Non-smoking Lung Cancer in East Asia Delineates Molecular Signatures of Pathogenesis and Progression
(2020-07-09)
Chen, Yi-Ju
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Roumeliotis, Theodoros, I
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Chang, Ya-Hsuan
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Chen, Ching-Tai
;
Han, Chia-Li
Lung cancer in East Asia is characterized by a high percentage of never-smokers, early onset and predominant EGFR mutations. To illuminate the molecular phenotype of this demographically distinct disease, we performed a deep comprehensive proteogenomic study on a prospectively collected cohort in Taiwan, representing early stage, predominantly female, non-smoking lung adenocarcinoma. Integrated genomic, proteomic, and phosphoproteomic analysis delineated the demographically distinct molecular attributes and hallmarks of tumor progression. Mutational signature analysis revealed age- and gender-related mutagenesis mechanisms, characterized by high prevalence of APOBEC mutational signature in younger females and over-representation of environmental carcinogen-like mutational signatures in older females. A proteomics-informed classification distinguished the clinical characteristics of early stage patients with EGFR mutations. Furthermore, integrated protein network analysis revealed the cellular remodeling underpinning clinical trajectories and nominated candidate biomarkers for patient stratification and therapeutic intervention. This multi-omic molecular architecture may help develop strategies for management of early stage never-smoker lung adenocarcinoma.