Browsing by Author "Lin, GM"

Now showing 1 - 6 of 6

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.
Anomalous variations of OFF-state leakage current in poly-Si TFT under static stress
(2002-05-01)
Chang, KM
;
Chung, YH
;
Lin, GM
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
In this letter, we study the anomalous variations of the OFF-state leakage current (I-OFF) in n-channel poly-Si thin-film transistors (TFTs) under static stress. The dominant mechanisms for the anomalous I-OFF can be attributed to 1) I-OFF increases due to channel hot electrons trapping at the gate oxide/channel interface and silicon grain boundaries and 2) I-OFF decreases due to hot holes accumulated/trapped near the channel/bottom oxide interface near the source region. Under the stress of high drain bias, serious impact ionization effect will occur to generate hot electrons and hot holes near the drain region. Some of holes will be injected into the gate oxide due to the vertical field (similar to(V_stress - V_ - Dstress) /T-ox) near the drain and the others will be migrated from drain to source along the channel due to lateral electric field (similar toV_Dstress/L-CH).
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.
Hot carrier induced degradation in the low temperature processed polycrystalline silicon thin film transistors using the dynamic stress
(2002-04-01)
Chang, KM
;
Chung, YH
;
Lin, GM
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The dynamic stress on low-temperature processed polycrystalline silicon thin-film transistors (poly-Si TFTs) is studied under two different stress conditions. As compared to static stress. the enhanced degradation in poly-Si TFT can be observed in dynamic stress. The enhanced degradation in dynamic stress (V-g = 0-20 V, V-ds = 22 V) is due to (1) the impact ionization effect in the ON state (V-gs = 20 V, V-ds = 22 V), (2) the drain avalanche hot carrier effect in the OFF state (V-gs = 0 V, V-ds = 22 V), and (3) the transient current stressing effect (at the switching period), However, in the stress condition of V-gs = -20 V to 20 V, V-ds = 0 V. both the source and drain regions are equally damaged. As the falling time becomes shorter, the transient current will increase to cause more device degradation near drain. It is also found that the degradation is more serious in short channel device than that in long channel device. As the stress frequency increases, the degradation will be enhanced. Moreover, the reduced degradation under high stress temperature is clue to reduced hot carrier effect under high temperature stressing.
The development of a DSP-based active small amplitude vibration control system for flexible beams by using the LQG algorithms and intelligent materials
(1996-12-12)
Bai, MR
;
Lin, GM
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
An active vibration control system is proposed for suppressing the small amplitude random vibrations in flexible beams. Intelligent materials such as the piezoelectric ceramic PZT are used as the actuator and the piezoelectric plastic PVDF is used as the sensor. The characteristics of the physical system are identified by a parametric modelling technique. The linear quadratic Gaussian (LQG) algorithm is employed for the controller design. The controller is implemented on the basis of a floating-point digital signal processor. The experimental results obtained by using the active vibration control system show significant attenuation of white noise disturbance in the frequency range of approximately 100-800 Hz. (C) 1996 Academic Press Limited
The development of a DSP-based active small amplitude vibration control system for flexible beams by using the LQG algorithms and intelligent materials
(1996-12-12)
Bai, MR
;
Lin, GM
;
機械工程學系
;
Department of Mechanical Engineering
An active vibration control system is proposed for suppressing the small amplitude random vibrations in flexible beams. Intelligent materials such as the piezoelectric ceramic PZT are used as the actuator and the piezoelectric plastic PVDF is used as the sensor. The characteristics of the physical system are identified by a parametric modelling technique. The linear quadratic Gaussian (LQG) algorithm is employed for the controller design. The controller is implemented on the basis of a floating-point digital signal processor. The experimental results obtained by using the active vibration control system show significant attenuation of white noise disturbance in the frequency range of approximately 100-800 Hz. (C) 1996 Academic Press Limited