Browsing by Author "Lin, JH"

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A new process-variation-immunity method for extracting capacitance coupling coefficients in flash memory cells
(2002-07-01)
Cho, CYS
;
Chen, MJ
;
Lin, JH
;
Chen, CF
;
電子工程學系及電子研究所
Overestimation of capacitance coupling coefficients in flash memory cells is encountered in the subthreshold slope method. By means of a two-parameters subthreshold current model I-D = I-o exp[q(V-GB - nV(SB))/nkT], a mathematical formulation of the subthreshold swing ratio in the subthreshold slope method is constructed to isolate the measurement errors caused by process variations from the errors traditionally caused by bulk capacitance coupling. To minimize the effect of process variations, a new method is developed based on the model. In this method, the control gate voltage shift due to weak body effect is measured in flash memory cells in subthreshold, while the corresponding slope factor n is adequately deduced from threshold voltage versus source-to-substrate bias measurement in dummy devices. The corrected capacitance coupling coefficients show large improvements compared to the design values, and the updated errors are found to be close to that caused solely by bulk capacitance coupling. The method is also fast since only a small source-to-substrate bias of 0.1 V is needed for implementation of weak body effect, and thereby it can be used as an in-line monitor of capacitance coupling coefficients.
A novel algal toxicity testing technique for assessing the toxicity of both metallic and organic toxicants
(2005-05-01)
Lin, JH
;
Kao, WC
;
Tsai, KP
;
Chen, CY
;
環境工程研究所
This study presents a closed-system algal toxicity test technique that is capable of detecting the effects of both organic and metallic toxicants. Toxicity testing was conducted by transferring adequate amounts of algal suspension, dilution water (with culture growth medium), and toxicants into 300-mL BOD bottles. The BOD bottles were completely filled up with no head-space left. The initial cell density and the exposure time were 15,000 cells/mL and 48 h, respectively. The performance of the above test method was evaluated using three heavy metals and six organic toxicants based on three different test endpoints, i.e., dissolved oxygen production, algal growth rate, and cell density. The proposed test revealed excellent test sensitivity and reproducibility. Currently, none of the existing algal toxicity test protocols is adequate for assessing the toxicity of organic chemicals. The closed-system algal toxicity tests developed by previous researchers also may not be ideal because the enlarged headspace and/or enriched bicarbonate buffer may result in either underestimations of the exposure concentrations or insensitive responses to both heavy metals and organic toxicants. Compared to the aforementioned algal toxicity test methods, the proposed technique in the present study has a more general applicability under conditions such as effluent samples containing both metals and organic toxicants or samples with unknown compositions. (c) 2005 Elsevier Ltd. All rights reserved.
A novel high-performance poly-silicon thin film transistor with a self-aligned thicker sub-gate oxide near the drain/source regions
(2001-10-01)
Chang, KM
;
Chung, YH
;
Lin, GM
;
Lin, JH
;
Deng, CG
In this letter, a novel high-performance poly-silicon thin-film transistor (poly-Si TFT) with a self-aligned thicker sub-gate oxide near the drain/source regions is proposed. Poly-Si TFTs with this new structure have been successfully fabricated and the results demonstrate a higher on-off current ratio of 5.9 x 10(6) and also shows the off-state leakage current 100 times lower than those of the conventional ones at V-GS = -15 V and V-DS = 10 V. Only four photo-masking steps are required and fully compatible with the conventional TFT fabrication processes. This novel structure is a good candidate for the further high-performance large-area device applications.
A study on seismic pounding probability of buildings in Taipei metropolitan area
(2002-03-01)
Lin, JH
;
Weng, CC
;
土木工程學系
;
Department of Civil Engineering
This study investigates the seismic pounding probability of buildings in the Taipei metropolitan area. Detailed procedures of the analytical method are presented. The results indicate that the building separation specified in the Seismic Provisions of the 1997 Taiwan Building Code (TBC'97) generally provides a relatively conservative estimate compared to that specified in the 19,94 Uniform Building Code (UBC'94) for the required distance to avoid pounding. This observation is demonstrated by comparing both the separation distance and/or the pounding probability of adjacent buildings based on the TBC'97 with those based on the UBC'94. The comparison results also reveal that the building separation distance specified by the TBC'97 is 1.6 times that specified by the UBC94 for the same building and site soil condition. If a reduction coefficient of 0.375 is adopted instead of the 0.6 specified in the TBC'97 to consider the effect of vibration phase difference of adjacent buildings, the critical pounding risk of the TBC'97 and the UBC'94 will be similar.
An alternative process for silicon nanowire fabrication with SPL and wet etching system
(2004)
Chang, KM
;
You, KS
;
Lin, JH
;
Sheu, JT
;
電子工程學系及電子研究所
Silicon nanowire fabrication of nanoscale dimensions on a single-crystal silicon surface by scanning probe lithography (SPL) and potassium hydroxide (KOH) aqueous wet etching system has proven to be adequate technological processes. Using SPL directly to define patterns on a single-crystal silicon surface showed that the linewidth of similar to50 nm can be further shrunk to similar to20 nm with KOH wet etching and orientation-dependent etching (ODE) processes on (110)-oriented silicon samples. In addition, this lithography technique also showed a great ability to define patterns on fluorocarbon mask layers. This method performed the fine linewidth of silicon nanowires around 20 nm by operating with lower applied voltages and higher scanning speeds (shorter exposure time) with SPL and ODE techniques and KOH wet etching on (100)-oriented silicon samples. These alternative processes provide the capability to fabricate nanoscale structures with high reliability and repeatablility for applications in the nanofields. (C) 2004 The Electrochemical Society.
Cavity configurations for soft-aperture Kerr-lens mode locking and multiple-period bifurcations in Ti : sapphire lasers
(2001-08-01)
Lin, JH
;
Wei, MD
;
Hsieh, WF
;
光電工程學系
;
Department of Photonics
We find that soft-aperture Kerr-lens mode locking (SAKLM) in a Ti:sapphire laser always takes place around certain discrete cavity configurations accompanied by peculiar beam patterns. By correlating the superposition of proper transverse modes to the observed beam patterns and fitting the beat frequencies to the resonance equation, we discovered that the patterns for SAKLM are formed by phase locking of the fundamental mode with specific degenerate transverse modes that occur near different degenerate cavity configurations. As predicted by the stability analysis, period-3 and period-2 SAKLM does occur around the 1/3- and 1/4-degenerate cavity configurations, which cannot be fully explained in terms of total mode locking of TEM00 and TEM01 modes. (C) 2001 Optical Society of America.
Characterization of the novel polysilicon TFT with a subgate coupling structure
(2002-04-01)
Chang, KM
;
Chung, YH
;
Deng, CG
;
Chung, YF
;
Lin, JH
We have proposed and fabricated a novel polysilicon thin film transistor (poly-Si TFT) with a subgate coupling structure that behaves as an offset gated structure in the OFF state while acting as a conventional nonoffset structure in the ON state. The OFF state leakage current of the new TFT is two orders of magnitude lower than that of the conventional nonoffset TFT, while the ON current of the new TFT is one order of magnitude higher than that of the offset TFT and is almost identical to that of the conventional non-offset TFT. The ON/OFF current ratio of the new TFT is greatly improved by two orders of magnitude. No additional photo-masking steps are required to fabricate the subgate of the new TFT and its fabrication process is fully the same as the conventional nonoffset TFTs.
Effect of carrier gas on the structure and electrical properties of low dielectric constant SiCOH film using trimethylsilane prepared by plasma enhanced chemical vapor deposition
(2004-12-22)
Cheng, YL
;
Wang, Y
;
Lan, JK
;
Chen, HC
;
Lin, JH
For a low dielectric constant inter-metal dielectric application, the low-k SiCOH film with a dielectric constant of 2.8-3.2 has been deposited by plasma-enhanced chemical vapor deposition (PE-CVD) with trimethylsilane (3MS), oxygen, and the carrier gas. In this work, we present the effects of the carrier gas on the characterizations of the low-k films, including reaction mechanism, the deposition rate, and the mechanical and electrical properties. According to the experimental results, the low-k film in Ar carrier gas exhibits the improvement in deposition rate, nonuniformity, leakage current, and hardness. In addition, the dielectric constant of the deposited low-k film is slightly sacrificed due to the decrease of micropores in the deposited films. (C) 2004 Elsevier B.V. All rights reserved.
Enhanced degradation in polycrystalline silicon thin-film transistors under dynamic hot-carrier stress
(2001-10-01)
Chang, KM
;
Chung, YH
;
Lin, GM
;
Deng, CG
;
Lin, JH
We address the mechanisms responsible for the enhanced degradation in the polysilicon thin-film transistors under dynamic hot-carrier stress. Unlike the monotonic decrease of maximum transconductance (G(m max)) in static stress, G(m max) in dynamic stress is initially increased due to the channel shortening effect by holes injected into the gate oxide near the drain region and then decreased due to tail states generation at the gate oxide/channel interface and grain boundaries. The threshold voltage variations are dominated by two degradation mechanisms: 1) breaking of weak bonds and 2) breaking of strong bonds to obey the power-time dependence law with a slope of 0.4. The degradation of the sub-threshold slope is attributed to intra-grain bulk states generation.
Evaluation of dynamic vehicle load on bridge decks
(2004-09-01)
Lin, JH
;
Weng, CC
;
土木工程學系
;
Department of Civil Engineering
Developed herein is a spectral approach for evaluating the dynamic vehicle load due to the passage of a vehicle moving at constant speed along a rough bridge surface. Based on the approach, a simple closed-form solution for predicting the variation of dynamic vehicle load on a bridge deck is derived. Numerical examples of the application of the solution to a simply-supported bridge are presented. Four different classes of pavement roughness (including: very good, good, average, and poor pavements) and three different vehicle speeds (speeds of 60, 100, and 140 km/h) are used in numerical analysis. The Dynamic Load Coefficient (DLC), a parameter used to characterize the magnitude of dynamic vehicle load, is estimated. The effects of vehicle speed and pavement roughness on the variation of dynamic vehicle load are investigated. It is concluded that if the effect of engine motion on vehicle vibration is disregarded, both the DLC and standard deviation of dynamic vehicle load are proportional to the square root of the pavement roughness coefficient S(no) for a specified vehicle speed.
Generation of wavelength-tunable optical pulses using a linear-cavity fiber laser scheme with a Fabry-Perot laser diode
(2004-04-01)
Peng, PC
;
Lin, JH
;
Chi, S
;
光電工程學系
;
Department of Photonics
A wavelength-tunable mode-locked linear-cavity fiber laser was demonstrated using a Fabry-Perot laser diode. By adding a tunable bandpass filter within the linear cavity, the wavelength-tunable fiber laser was easy to be tuned dynamically. This linear-cavity fiber laser output exhibited a good performance having the optical sidemode suppression ratio over 30 dB and the wavelength-tuning range up to 27 nm. Furthermore, this fiber laser generated pulses with pulsewidth between 53.2 and 80.4 ps at a repetition frequency of 908.39 MHz.
Generation of wavelength-tunable optical pulses using EDFA as external-injection light source and amplifier for Fabry-Perot laser diode
(2004-11-01)
Peng, PC
;
Peng, WR
;
Lin, JH
;
Lin, WP
;
Chi, S
We propose and experimentally demonstrate a system for the generation of wavelength-tunable pulses using a gain-switched Fabry-Perot laser diode (FPLD) and an erbium-doped fiber amplifier (EDFA). The EDFA is used as both an external-injection light source and an amplifier for the FPLD. The wavelength tuning is achieved by a tunable filter. The optical sidemode suppression ratio of this system is better than 32 dB over the wavelength-tunable range of 34.5 nm. Moreover, the repetition frequency is 2000 MHz, and the pulsewidth is between 49.3 and 65.3 ps. The whole system is simple and can be easily constructed.
Harmonic mode locking and multiple pulsing in a soft-aperture Kerr-lens mode-locked Ti : sapphire laser
(2002-10-15)
Lin, JH
;
Hsieh, WF
;
Wu, HH
;
光電工程學系
;
Department of Photonics
We report the observation of harmonic mode locking and multiple pulse operations in a soft-aperture Kerr-lens mode-locked Ti:sapphire laser by varying the total intra-cavity dispersion. Second, third, and fourth order harmonic mode locking as well as multiple pulsing with interpulse separation ranging from femtosecond to nanosecond are observed. The laser is characterized in these regimes in terms of wavelength, bandwidth, pulsewidth, average and peak powers as functions of group velocity dispersion. By introducing a loss difference term into gain dynamic analysis, we conclude that gain depletion and recovery mechanisms are responsible for the underlying physics of current observations. (C) 2002 Elsevier Science B.V. All rights reserved.
Hierarchical floorplan design on the Internet
(1999)
Lin, JH
;
Jou, JY
;
Jiang, HR
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
With the proliferation of transistor count in VLSI design, more and more design groups try to figure out a way to efficiently combine their designs. The Internet features distributed computing and resource sharing. Consequently, a hierarchical floorplan design can be adequately solved bl the Internet environment. In this paper, we address the problem of area minimization floorplan design in the Internet environment. We propose a novel algorithm, RMG algorithm. Taking advantage of the Internet, RMG algorithm reduces the computing time by shortening the critical path in the floorplan tl ee. With creating floorplan design in the Internet environment, it cart be seen that the Internet advantages Electronic Design Automation (EDA).
Improving contour accuracy by fuzzy-logic enhanced cross-coupled precompensation method
(2004-02-01)
Chin, JH
;
Cheng, YM
;
Lin, JH
;
機械工程學系
;
Department of Mechanical Engineering
Contour accuracy is obtained by efforts in algorithms. Most motion control algorithms reduce either position error or contour error to gain accuracy. In this paper, we investigate the idea of constructing a Fuzzy-logic controller to a proven algorithm, the cross-coupled precompensation method (CCPM), and using both position and contour error to generate compensation term. Simulation comparison with known methods and experimental comparisons among the uncoupled system, the cross-coupled system, the original CCPM and the proposed method were given. It was shown that the performance of the original CCPM was further enhanced. The proposed method also showed a better performance when subjected to external load. (C) 2003 Elsevier Ltd. All rights reserved.
Intelligent call admission control for differentiated QoS provisioning in wideband CDMA cellular systems
(2000)
Chang, CJ
;
Shen, S
;
Lin, JH
;
Ren, FC
;
電信工程研究所
In this paper, we propose intelligent call admission control for wideband CDMA cellular systems to support differentiated QoS requirements. The intelligent call admission controller (ICAC) adopts fuzzy and neural network techniques to make admission decision for a new call request by considering the QoS measures of all service types, predicted next-step existing-call interference, and estimated new-call interference. It contains a fuzzy call admission processor, a pipeline recurrent neural network (PRNN) interference predictor, and a fuzzy equivalent interference estimator. Simulation results indicate that ICAC attains better performance in keeping QoS guaranteed, blocking probability and admitted number of users. Furthermore, ICAC is more adaptive and stable than SIR-based CAC in wideband CDMA cellular systems.
Intensity and wavelength-division multiplexing FBG sensor system using a tunable multiport fiber ring laser
(2004-01-01)
Peng, PC
;
Lin, JH
;
Tseng, HY
;
Chi, S
;
光電工程學系
We propose an intensity and wavelength-division multiplexing (IWDM) fiber Bragg grating (FBG) sensor system using a tunable multiport fiber ring laser. The different output powers of a multiport fiber laser are used to address the information reflected from the sensing FBGs, even if the Bragg wavelengths of the FBGs connected at different laser output ports are identical. We describe the operation principle and experimentally demonstrate a three-port fiber sensor. For the IWDM technique, our proposed fiber grating sensor system can enhance the sensing capacity, signal-to-noise ratio, and sensing resolution.
Interfacial mechanism studies of electroless plated Cu films on a-Ta : N layers catalyzed by PIII
(2002-05-01)
Lin, JH
;
Lee, TL
;
Hsieh, WJ
;
Lin, CC
;
Kou, CS
This study evaluated the interface reaction and crystallography of the electroless plated copper film (similar to0.2 mum thick) catalyzed by plasma immersion ion implanted (PIII) Pd on the 150-Angstrom-thick amorphous tantalum nitride (a-Ta:N) barrier layer. The copper plated specimens were annealed at various temperatures in an ambient atmosphere of 90% nitrogen + 10% hydrogen mixed gases. Sheet resistivity, Auger electron spectroscopy (AES) analyses showed that the PIII Pd atoms were diffused into the copper layer from the interface of a-Ta:N and copper layers after 500 degreesC annealing for 1 h. Results based on x-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) showed a phase transformation from a-Ta:N into crystallized Ta2N phase at annealing. The Cu(111) texture was strengthened at 300degreesC annealing for I h because of the relaxation of the residual stress and recovery of the copper film. The texture was reduced at the 500 degreesC annealing for I h because of the copper grain growth. The adhesion strength of copper films on a-Ta:N barrier layer was enhanced by the annealing because of the interdiffusion of copper layer, Pd clusters and a-Ta:N barrier layer. The annealing temperatures lower than 300 degreesC help to reduce the electric resistivity of copper film, to strengthen the Cu(111) preferred orientation. and to enhance the adhesion strength of copper films on a-Ta:N layer. However, the specimen annealed at 500 'C manifested the diffusion of Pd atoms into the copper film and resulted in a significant increase of the electric resistivity of copper film. (C) 2002 American Vacuum Society.
Internet-based hierarchical floorplan design
(1999-11-01)
Lin, JH
;
Jou, JY
;
Jiang, IHR
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
With the proliferation of the transistor count in VLSI design, more and more design groups try to figure out an efficient way to combine their designs. The Internet features distributed computing and resource sharing. Consequently, a hierarchical design can adequately be solved in the Internet environment. In this paper, we demonstrate the facilitation of the Internet environment by solving the area minimization floorplan problem. We propose the RMG algorithm taking advantage of the Internet. Based on the model of transfer latencies, the RMG algorithm reduces the computing time by shortening the critical path in the floorplan tree. Our experimental results show that the Internet is suitable for Electronic Design Automation (EDA).
Low threshold and high power output of a diode-pumped nonlinear mirror mode-locked Nd : GdVO4 laser
(2005-08-22)
Lin, JH
;
Yang, WH
;
Hsieh, WF
;
Lin, KH
;
光電工程學系
We demonstrated nonlinear mirror mode-locking of a diode-pumped Nd:GdVO4 laser by using a 10 mm long KTP crystal. The stable CW mode locking can be reached with the relative low threshold pump power as low as 2.3W. The highest output power of 2.65W at the 10W pump powers are generated with the 121-MHz repetition rate of pulses. It confirms the excellent laser performance of the Nd: GdVO4 for high-peak power of the pulse operation. (c) 2005 Optical Society of America.