Browsing by Author "Chiu, KY"

Now showing 1 - 10 of 10

A study on the radiation hardness of flash cell with horn-shaped floating-gate
(1997-09-01)
Huang, TY
;
Jong, FC
;
Chao, TS
;
Lin, HC
;
Leu, LY
The effects of radiation on the characteristics of split-gate electrical erasable programmable read only memory (EEPROM)/flash cells with recently-proposed horn-shaped floating gates are studied in terms of cell read current; data retention, cycling endurance, program/erase efficiency, threshold voltage and junction leakage. Our results show that the cells appear to survive after 1 Mrad (Si) Co-60 irradiation. Moreover, the after-irradiation cell read current actually increases in the ''erase'' (i.e., low-threshold voltage, high-conducting) state (i.e., improves), albeit the cell read current also increases in the ''program'' (i.e., high-threshold voltage, low-conducting) state (i.e., a degradation). Our results also show that, despite an improvement in the initial read current in the ''erase'' state immediately after radiation, the write/erase cycling endurance of the flash cells is significantly impeded after irradiation, due to a much faster ''window closure'' rate in the ''erase'' state, although the cell read current is found to remain relatively stable in the ''program'' state after cycling.
A study on the radiation hardness of flash cell with horn-shaped floating-gate
(1997-09-01)
Huang, TY
;
Jong, FC
;
Chao, TS
;
Lin, HC
;
Leu, LY
The effects of radiation on the characteristics of split-gate electrical erasable programmable read only memory (EEPROM)/flash cells with recently-proposed horn-shaped floating gates are studied in terms of cell read current; data retention, cycling endurance, program/erase efficiency, threshold voltage and junction leakage. Our results show that the cells appear to survive after 1 Mrad (Si) Co-60 irradiation. Moreover, the after-irradiation cell read current actually increases in the ''erase'' (i.e., low-threshold voltage, high-conducting) state (i.e., improves), albeit the cell read current also increases in the ''program'' (i.e., high-threshold voltage, low-conducting) state (i.e., a degradation). Our results also show that, despite an improvement in the initial read current in the ''erase'' state immediately after radiation, the write/erase cycling endurance of the flash cells is significantly impeded after irradiation, due to a much faster ''window closure'' rate in the ''erase'' state, although the cell read current is found to remain relatively stable in the ''program'' state after cycling.
Bistable resistive switching of a sputter-deposited Cr-doped SrZrO3 memory film
(2005-06-01)
Liu, CY
;
Wu, PH
;
Wang, A
;
Jang, WY
;
Young, JC
Sputter-deposited Cr-doped SrZrO3-based metal-insulator-metal structures exhibited bistable resistive reversible switching as observed under bias voltage and voltage pulse. The ratio of resistance of the two leakage states (high-H, low-L) was about five orders of magnitude. The conduction of the L-state satisfied Frenkel-Poole emission and that of the H-state followed ohmic mechanism, causing the resistance ratio to decrease with increasing bias voltage. The transition time of H- to L-state was five orders of magnitude higher than that of L- to H-state. The transition from H- to L-state was the restricted part for reversible switching operation. The difference in transition time of the two states should be related to the respective conduction mechanisms.
Characterization and Modeling of on-chip spiral inductors for Si RFICs
(2002-02-01)
Chao, CJ
;
Wong, SC
;
Kao, CH
;
Chen, MJ
;
Leu, LY
The paper presents a complete characterization of on-chip inductors fabricated in BiCMOS technology. First, a study of the scaling effect of inductance on geometry and structure parameters is presented to provide a clear guideline on inductor scaling with suitable quality factors. The substrate noise analysis and noise reduction techniques are then investigated. It is shown that floating well can improve both quality factor and noise elimination by itself under 3 GHz and together with a guard ring above 3 GHz. Finally, for accurate circuit simulations, a new inductor model is developed for predicting the skin effect and eddy effect and associated quality factor and inductance.
Effects of floating-gate doping concentration on flash cell performance
(1997-08-01)
Huang, TY
;
Jong, FC
;
Lin, HC
;
Chao, TS
;
Leu, LY
In this paper we report the effects on flash cell performance of the doping concentration of the horn-shaped floating-gate. It is demonstrated that the Boating-gate doping concentration not only determines the work function of the floating-gate, but also affects the resultant interpoly oxide. As a result, the Bash cell performance is affected by the Boating-gate doping concentration, and should therefore be carefully designed. It is shown that a low doping level (e.g., <1.7x10(18) cm(-3)) on the Boating-gate results in a high threshold voltage of the flash cell, low cell read current, and degraded write/erase cycling endurance. Flash cells with a medium (e.g., 1.7 x 10(19) cm(-3)) doping level, on the other hand, depict the lowest threshold voltage, and the highest cell read current; while Bash cells with the highest doping level (1.7x10(20) cm(-3)) used in this study depict a medium threshold voltage. This could be ascribed to the fact that both medium and high doping levels result in a degenerate polysilicon floating-gate with a similar work function; however, a higher doping concentration results in a thicker interpoly oxide, and therefore a higher threshold voltage, and lower read current.
Improved flash cell performance by N2O annealing of interpoly oxide
(1997-07-01)
Jong, FC
;
Huang, TY
;
Chao, TS
;
Lin, HC
;
Leu, LY
In this letter, we report the effects of N2O annealing of interpoly oxide on flash cell performance. It is demonstrated that by adding an N2O anneal after interpoly oxide formation, improved cycling endurance is achieved, The program and erase efficiencies are also improved significantly, compared to the control cell without N2O anneal. The cells with N2O anneal show higher cell current (i.e., drain current), which can be ascribed to a lower threshold voltage and higher transconductance, compared to the control cell.
Improving radiation hardness of EEPROM/flash cell by N2O annealing
(1998-07-01)
Huang, TY
;
Jong, FC
;
Chao, TS
;
Lin, HC
;
Leu, LY
The effects of an N2O anneal on the radiation effects of a split-gate electrical erasable programmable read only memory (EEPROM)/flash cell with a recently-proposed horn-shaped floating gate were studied. We have found that although the cells appear to survive 1 Mrad(Si) Co-60 irradiation without data retention failure, the write/erase cycling endurance was severely impeded after irradiation. Specifically, the write/erase cycling endurance was degraded to 20 K from the pre-irradiation value of 50 K, However, by adding an N2O annealing step after the interpoly oxidation, the after-irradiation write/erase cycling endurance of the resultant cell can be significantly improved to over 45 K, N2O annealing also improves the after-irradiation program and erase efficiencies. The N2O annealing step therefore presents a potential method for enhancing the robustness of the horn-shaped floating-gate EEPROM/flash cells for radiation-hard applications.
Lane detection using color-based segmentation
(2005)
Chiu, KY
;
Lin, SF
;
電控工程研究所
;
Institute of Electrical and Control Engineering
Lane boundary detection is the problem of estimating the geometric structure of the lane boundaries of a road on the images captured by a camera. To be an intelligent vehicle, lane boundary is necessary information, so the system and the algorithm should be as simple and fast as possible. In this paper, we propose a new method based on color information and this method will be applicable in complex environment. In this system, we first choose a region of interest to find out a threshold using statistical method in a color image. The threshold then will be used to distinguish possible lane boundary from the road. We use color-based segmentation to find out the lane boundary and use a quadratic function to approach it. This system demands low computational power and memory requirements, and is robust in the presence of noise, shadows, pavement, and obstacles such like cars, motorcycles and pedestrians conditions. The result images can be used as pre-processed images for lane tracking, road following or obstacle detection.
Memory effect of sol-gel derived V-doped SrZrO3 thin films
(2006-01-03)
Liu, CY
;
Chuang, CC
;
Chen, JS
;
Wang, A
;
Jang, WY
V-doped SrZrO3 (SZO) thin films on LaNiO3/SiO2/Si substrate are synthesized by sol-gel method to form metal-insulator-metal (MIM) sandwich structure. The physical and electrical properties of the MIM device are studied. The structure and surface morphology of the SZO films are also characterized by X-ray diffraction and scanning electron microscopy. Such a device has the bistable switching properties of current-voltage characteristics. The resistive switching between high state and low state can also be operated with voltage pulses. The device with the properties of long retention time and non-destructive readout is expected to be suitable for nonvolatile memory application. (c) 2005 Elsevier B.V. All rights reserved.
New insights on RF CMOS stability related to bias, scaling, and temperature
(2000)
Su, JG
;
Wong, SC
;
Chang, CY
;
Chiu, KY
;
Huang, TY
The stability issues of CMOS devices for RF applications were studied. The stability factor of MOS devices based on the small-signal model (SSM) parameters was derived, for the first time. The results reveal some new insights on the effects of biasing, and scaling parameters on the stability; and were subsequently confirmed by our experimental results. Our results also show that unconditional stability of RF CMOS devices can be obtained with proper biasing and device geometries. Finally, the effects of temperature on stability were also: investigated. Our results suggest that careful attention needs to be paid for stable low temperature operation.