Browsing by Author "Chen, Y. C."

Now showing 1 - 20 of 35

A FLEXIBLE, NON-INTRUSIVE POWER SENSOR TAG FOR THE ELECTRICITY MONITORING OF TWO-WIRE HOUSEHOLD APPLIANCES
(2012)
Chen, Y. C.
;
Hsu, W. H.
;
Cheng, S. H.
;
Cheng, Y. T.
;
交大名義發表
This paper presents a flexible non-intrusive power sensor tag with good proximity for accurate electric current and voltage sensing on a typical SPT-2 18AWG zip-cord power line of household appliances. The current and voltage sensors are simultaneously fabricated on a 100 mu m-thick flexible PET substrate. For the design of a 50-turns coil combing with two sensing electrodes in an area of 1.3x1cm(2), the sensor tag exhibits a sensitivity of 31.1 mu V/A and 98.9mV/115V for detecting 60Hz electric current and voltage, respectively.
A LOW-POWER MILLIWATT ELECTROMAGNETIC MICROSPEAKER USING A PDMS MEMBRANE FOR HEARING AIDS APPLICATION
(2011)
Chen, Y. C.
;
Cheng, Y. T.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper demonstrates a low-power electromagnetic microspeaker with a PDMS membrane for hearing aids application. For a 1.76mW power input, the speaker with a 3.5mm in diameter and 3.3 mu m thick membrane can generate a sound with the sound pressure level (SPL) of 106dB @1kHz in a 2c.c. coupler.
A novel AOI system for OLED panel inspection
(2005)
Perng, D. B.
;
Chen, Y. C.
;
Lee, M. K.
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
Organic light emitting diode (OLED) technology uses substances that emit red, green, blue or white light. An OLED panel consists of stacks of several thin layers of different materials, as such it is not easy to inspect the common OLED defects. In this paper, an auto-optical inspection (AOI) system which can detect such defects effectively and robustly was proposed and developed. The proposed system can also identify, in which layer the defect occurred. Meanwhile, a moving mechanism coupled with a lighting mechanism was proposed and implemented for gabbing clear images. The proposed AOI system would provide great help in improving the OLED production process and the quality control process.
A STUDY ON RFID AND AGENT BASED SERVICE PLATFORM
(2011)
Chen, Ruey-Shun
;
Yeh, K-C
;
Chen, C. C.
;
Chen, Y. C.
;
資訊管理與財務金融系註：原資管所+財金所
In order to prevent the monetary loss due to the information gap, we propose the "RFID and agent based service platform", which uses the agent as the framework to construct the integrated information system mechanism. We also use the radio frequency identification technology to realize the intelligent shelf for the retrieval of commodity message. At the same time, we develop the interactive information platform to provide the consultation and promotion service of goods. The framework will help enhance the performance of the sales outlets and improve the customer service, while addressing the time effect issue of the popular commodity.
Compact high-pulse-energy passively Q-switched Nd:YLF laser with an ultra-low-magnification unstable resonator: application for efficient optical parametric oscillator
(2013-01-28)
Cho, C. Y.
;
Huang, Y. P.
;
Huang, Y. J.
;
Chen, Y. C.
;
Su, K. W.
We exploit an ultra-low-magnification unstable resonator to develop a high-pulse-energy side-pumped passively Q-switched Nd:YLF/Cr4+:YAG laser with improving beam quality. A wedged laser crystal is employed in the cavity to control the emissions at 1047 nm and 1053 nm independently through the cavity alignment. The pulse energies at 1047 nm and 1053 nm are found to be 19 mJ and 23 mJ, respectively. The peak powers for both wavelengths are higher than 2 MW. Furthermore, the developed Nd:YLF lasers are employed to pump a monolithic optical parametric oscillator for confirming the applicability in nonlinear wavelength conversions. (C) 2013 Optical Society of America
Damage of light-emitting diodes induced by high reverse-bias stress
(2009-01-15)
Chen, N. C.
;
Wang, Y. N.
;
Wang, Y. S.
;
Lien, W. C.
;
Chen, Y. C.
The ability of a nitride light-emitting diode (LED) to withstand electrostatic discharge (ESD) is important because of the insulating property of the sapphire substrate. Therefore, damage caused by ESD to a nitride LED is a valuable subject. However, damage is caused by ESD in a very short period, so monitoring its evolution is very difficult. Accordingly, ESD experiments are performed and the effects of a high reverse Current (HRC) on devices are investigated. Damage caused by ESD and HRC and their other effects on devices are compared. Four distinct effects of the ESD on devices are illustrated. (c) 2008 Elsevier B.V. All rights reserved.
Design and fabrication of a microplatform for the proximity effect study of localized ELF-EMF on the growth of in vitro HeLa and PC-12 cells
(2010-12-01)
Chen, Y. C.
;
Chen, C. C.
;
Tu, W.
;
Cheng, Y. T.
;
Tseng, F. G.
This paper presents a platform technology with experimental results that show the scientists and biologists a way to rapidly investigate and analyze the biological effects of localized extremely low frequency (ELF) electromagnetic field (EMF) on living cells. The proximity effect of the localized ELF-EMF on living cells is revealed using the bio-compatible microplatform on which an on-glass inductive coil array, the source of the localized ELF-EMF in micro scale, is designed, fabricated and operated with a field strength of 1.2 +/- 0.1 mT at 60 Hz for cell culturing study. After a 72 h ELF-EMF exposure, HeLa (human cervical cancer) and PC-12 (rat pheochromocytoma) cells exhibit about 18.4% and 12.9% cell proliferation rate reduction, respectively. Furthermore, according to the presented dynamic model, the reduction of the proliferation can be attributed to the interference of signal transduction processes due to the tangential currents induced around the cells.
Design and fabrication of a microplatform for the proximity effect study of localized ELF-EMF on the growth of in vitro HeLa and PC-12 cells
(2010-12-01)
Chen, Y. C.
;
Chen, C. C.
;
Tu, W.
;
Cheng, Y. T.
;
Tseng, F. G.
This paper presents a platform technology with experimental results that show the scientists and biologists a way to rapidly investigate and analyze the biological effects of localized extremely low frequency (ELF) electromagnetic field (EMF) on living cells. The proximity effect of the localized ELF-EMF on living cells is revealed using the bio-compatible microplatform on which an on-glass inductive coil array, the source of the localized ELF-EMF in micro scale, is designed, fabricated and operated with a field strength of 1.2 +/- 0.1 mT at 60 Hz for cell culturing study. After a 72 h ELF-EMF exposure, HeLa (human cervical cancer) and PC-12 (rat pheochromocytoma) cells exhibit about 18.4% and 12.9% cell proliferation rate reduction, respectively. Furthermore, according to the presented dynamic model, the reduction of the proliferation can be attributed to the interference of signal transduction processes due to the tangential currents induced around the cells.
Designer germanium quantum dot phototransistor for near infrared optical detection and amplification
(2015-02-06)
Kuo, M. H.
;
Lai, W. T.
;
Hsu, T. M.
;
Chen, Y. C.
;
Chang, C. W.
We demonstrated a unique CMOS approach for the production of a high-performance germanium (Ge) quantum dot (QD) metal-oxide-semiconductor phototransistor. In the darkness, low off-state leakage (I-off similar to 0.27 pA mu m(-2)), a high on-off current ratio (I-on/I-off similar to 10(6)), and good switching behaviors (subthreshold swing of 175 mV/dec) were measured on our Ge-QD phototransistor at 300 K, indicating good hetero-interfacial quality of the Ge-on-Si. Illumination makes a significant enhancement in the drain current of Ge QD phototransistors when biased at both the on-and off-states, which is a great benefit from Ge QD-mediated photoconductive and photovoltaic effects. The measured photocurrent-to-dark-current ratio (I-photo/I-dark) and the photoresponsivities from the Ge QD phototransistor are as high as 4.1 x 10(6) and 1.7 AW(-1), respectively, under an incident power of 0.9mW at 850 nm illumination. A superior external quantum efficiency of 240% and a very fast temporal response time of 1.4 ns suggest that our Ge QD MOS phototransistor offers great promise as optical switches and transducers for Si-based optical interconnects.
Direct observation of ferroelectric polarization-modulated band bending at oxide interfaces
(2012-03-19)
Huang, B. C.
;
Chen, Y. T.
;
Chiu, Y. P.
;
Huang, Y. C.
;
Yang, J. C.
This study presents a direct visualization of the influences of ferroelectric polarization on the electronic properties of the Schottky contact at the Nb-SrTiO3/BiFeO3 hetero-interface using scanning tunneling microscopy and spectroscopy (STM/S). The evolution of the local density of states across the Nb-SrTiO3/BiFeO3 interface reveals the interfacial band alignment and the characteristic quantities of the metal/ferroelectric contact. The unique combination of STM and STS in this study delivers an approach to obtain critical information on the interfacial electronic configurations of ferroelectric oxide interfaces and also their variation with ferroelectric polarization switching. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3691615]
Domain growth dynamics in single-domain-like BiFeO(3) thin films
(2009-03-23)
Chen, Y. C.
;
Lin, Q. R.
;
Chu, Y. H.
;
材料科學與工程學系
;
Department of Materials Science and Engineering
We present a quantitative study of 180 degrees domain wall motion in epitaxial BiFeO(3) (111) films, which can be treated as a nearly ideal single-domain environment. The domains were dynamically written by applying voltage pulses and examined by the piezoresponse force microscope technique. A transition of domain growth behaviors from the activated type to the nonactivated type was observed when increasing the pulse voltages. The obtained activation field was close to the ideally thermodynamic switching field of BiFeO(3). The asymmetry of activated fields showed the preference of the downward polarization in the BiFeO(3)/SrRuO(3) films.
Domain growth dynamics in single-domain-like BiFeO3 thin films
(2009-03-23)
Chen, Y. C.
;
Lin, Q. R.
;
Chu, Y. H.
;
材料科學與工程學系
;
Department of Materials Science and Engineering
We present a quantitative study of 180 degrees domain wall motion in epitaxial BiFeO3 (111) films, which can be treated as a nearly ideal single-domain environment. The domains were dynamically written by applying voltage pulses and examined by the piezoresponse force microscope technique. A transition of domain growth behaviors from the activated type to the nonactivated type was observed when increasing the pulse voltages. The obtained activation field was close to the ideally thermodynamic switching field of BiFeO3. The asymmetry of activated fields showed the preference of the downward polarization in the BiFeO3/SrRuO3 films.
Effective surface treatments for selective epitaxial SiGe growth in locally strained pMOSFETs
(2007-01-01)
Cheng, P. L.
;
Liao, C. I.
;
Wu, H. R.
;
Chen, Y. C.
;
Chien, C. C.
Several dry and wet surface treatment methods are explored for a selective SiGe epitaxial film used to fabricate embedded SiGe pMOSFETs. Pre-clean conditions for the device wafers used in this study were limited by a realistic CMOS process window with tight thermal and chemical budgets due to dopant diffusion and hardmask erosion concerns. The effectiveness of these pre-clean methods is evaluated by SiGe epitaxial film quality and SIMS profiles of key residual contaminants such as C and O at the SiGe-Si substrate interface. As an effective low-temperature dry surface treatment, chemical bake in HCl/H-2 at temperature below 800 degrees C is found to reduce interface C and O peak concentrations by an order of magnitude. Wet clean in multiple cycles of DIW-O-3 (ozonated water), SC1 and diluted HF (DHF) is also presented to prepare epitaxial growth surfaces with accumulated damage and chemical residues from previous process steps. SiGe epitaxial film morphology is also observed to improve by increasing DHF clean time. For further improvement of film quality on the most difficult surfaces, Si seed layer was employed to initiate SiGe film nucleation and yield smooth film growth.
Enhanced light harvesting of Si solar cells via luminescent down-shifting using YVO4:Bi3+, Eu3+ nanophosphors
(2013-11-01)
Huang, C. K.
;
Chen, Y. C.
;
Hung, W. B.
;
Chen, T. M.
;
Sun, K. W.
The colloids of YVO4 nanoparticles on microtextured Si surface are demonstrated to have promising potential for efficient solar spectrum utilization in crystalline Si solar cells. The solar cells showed an enhancement of 4% in short-circuit current density and approximately 0.7% in power conversion efficiency when coated with YVO4 nanoparticles. The properties of cells integrated with YVO4 nanoparticles were characterized to identify the role of YVO4 in improved light harvesting. The current experiments conclude that the colloids of YVO4 nanoparticles not only act as luminescent down-shifting centers in the ultraviolet region but also serve as an antireflection coating for enhancing the light absorption in the measured spectral regime. Copyright (c) 2012 John Wiley & Sons, Ltd.
From symmetry to entropy: Crystal entropy difference strongly affects early stage phase transformation
(2019-12-23)
Hu, C. H.
;
Chen, Y. C.
;
Yu, P. J.
;
Fung, K. Y.
;
Hsueh, Y. C.
Although the connection between symmetry and entropy is not clear, researchers calculate configurational entropy with an ideal gas mixing model all along regardless of which structure they are considering. However, it is obvious that crystalline structures have symmetry, while an ideal gas does not. Therefore, the same ideal gas mixing value should not be assigned to other structures, such as face-centered-cubic (fcc) and hexagonal-close-packed (hcp) structures. Here, we offer a precise definition for determining the configurational entropy of crystals. We calculate the difference in configurational entropy between fcc and hcp structures based on Burnside's lemma in combinatorial mathematics and crystallographic rotation-point groups.
Genetically closely related azole-resistant Candida tropicalis in environments can be a threat to healthcare
(2018-06-01)
Zhou, Z. L.
;
Tsai, J. N.
;
Tseng, M. N.
;
Liu, H. L.
;
Lin, C. C.
High-density nano-pillar SiOx-based resistive switching memory using nano-sphere lithography to fabricate a one diode - one resistor (1D-1R) architecture
(2014-01-01)
Chang, Y. F.
;
Ji, L.
;
Chen, Y. C.
;
Zhou, F.
;
Tsai, T. M.
A highly compact, one diode - one resistor (1D-1R) nano-pillar device architecture has been demonstrated using nano-sphere lithography (NSL) to fabricate SiOx-based resistive switching (RS) memory. The intrinsic SiOx-based resistive switching element and Si-based PN diode are self-aligned on the epitaxial silicon wafer using NSL and a deep-Si-etch process without using conventional photolithography. The DC electrical performance, an AC pulse response in the 50 ns regime, capability for multi-bit operation, and high readout margin immunity for sneak path issue demonstrate good potential for high-speed nonvolatile memory (NVM). The NSL fabrication process is an efficient, economical approach to enable large-scale patterning of 1D-1R architectures while providing excellent NVM performance for future applications.
High-repetition-rate quasi-CW side-pumped mJ eye-safe laser with a monolithic KTP crystal for intracavity optical parametric oscillator
(2014-04-07)
Cho, C. Y.
;
Chen, Y. C.
;
Huang, Y. P.
;
Huang, Y. J.
;
Su, K. W.
We demonstrate a high-repetition-rate millijoule passively Q-switched eye-safe Nd:YVO4 laser pumped by a quasi-CW diode stack. A theoretical analysis has been explored for the design criteria of generating TEMn,0 mode in the diode-stack directly side-pumping configuration. We successfully generate TEMn,0 modes at 1064 nm by adjusting the gain medium with respected to the laser axis. We further observe the spatial cleaning ability for generating an nearly TEM0,0 mode output at 1573 nm with a monolithic OPO cavity. At the repetition rate up to 200 Hz, the output pulse energy reaches 1.21 mJ with the threshold pump energy of 17.9 mJ. (C) 2014 Optical Society of America
Improved fuzzy feedback linearization and Sinswat-transformation control of inverted pendulum
(2010)
Chien, T. L.
;
Chen, C. C.
;
Chen, Y. C.
;
Wu, S. L.
;
材料科學與工程學系
This paper studies the output tracking and almost disturbance decoupling problem of nonlinear control systems with uncertainties via fuzzy logic control and feedback linearization approach. The main contribution of this study is to construct a controller, under appropriate conditions, such that the resulting closed-loop system enjoys for any initial condition and bounded tracking signal the following characteristics: input-to-state stability with respect to disturbance inputs and almost disturbance decoupling, i.e., the influence of disturbances on the L(2) norm of the output tracking error can be arbitrarily attenuated by increasing some adjustable parameters. The underlying theoretical approaches are the differential geometry approach and the composite Lyapunov approach. One example, which cannot be solved by the approach from the first paper (Marino et al., 1989) on the almost disturbance decoupling problem, is proposed in this paper to exploit the fact that the almost disturbance decoupling and the convergence rate performances are easily achieved by virtue of our approach. In order to demonstrate the practical applicability, the paper takes up the study of an inverted pendulum control system.
Improved performances in low-voltage-driven InGaZnO thin film transistors using a SiO2 buffer layer insertion
(2014-06-01)
Zheng, Z. W.
;
Chen, Y. C.
;
光電系統研究所
;
Institute of Photonic System
In this paper, we report the device characteristics of indium gallium zinc oxide (IGZO) thin film transistors (TFTs) with high-kappa lanthanum aluminate (LaAlO3) based gate insulators. The IGZO TFT with single LaAlO3 gate insulator has an operation voltage as low as 1.5 V but suffers a low on-off-state drive current ratio (I (on)/I (off)) of 1x10(3), a large subthreshold swing (SS) of 0.405 V/dec and a small field effect mobility (mu (FE)) of 0.84 cm(2)/V sec. Inserting a SiO2 buffer layer between IGZO active channel layer and LaAlO3 gate insulator results in a reduced effective dielectric constant but with significant improved characteristics including a high I (on)/I (off) of 6.2x10(4), a small SS of 0.113 V/dec and a large mu (FE) of 5.2 cm(2)/V sec. Such good performances can be attributed to the lowered gate leakage and reduced interface trap issue owing to the smooth SiO2 buffer layer insertion.