Title :
Analysis and design of a-Si TFT/LCD panels with a pixel model
Author :
Kaneko, Yoshiyuki ; Sasano, Akira ; Tsukada, Toshihisa
Author_Institution :
Hitachi Ltd., Tokyo, Japan
fDate :
12/1/1989 12:00:00 AM
Abstract :
The design of a-Si thin-film-transistor/liquid-crystal-display (TFT/LCD) panels using a pixel model which consists of an equivalent electrical circuit and includes parasitic capacitance and the actual structure of deposited layers is discussed. The model´s validity is first confirmed by comparing calculations with experimental results on a-Si TFT switching characteristics and TFT/LCD electrooptical characteristics. The gradual-channel approximation of an MOS transistor is applied to the static I-V characteristic of a-Si TFTs. This approximation is successfully used to obtain an analytical expression for pixel electrode voltage during the TFT turn-on time. The calculated dependence of the LCD panel transmittance on signal voltage is shown to reproduce the experimental results. On the basis of the analysis, a TFT-addressed 5-in.-diagonal liquid-crystal color TV has been developed which exhibits excellent display quality
Keywords :
amorphous semiconductors; elemental semiconductors; equivalent circuits; flat panel displays; insulated gate field effect transistors; liquid crystal displays; semiconductor device models; silicon; thin film transistors; 5 in; LCD panel transmittance; MOS transistor; Si thin film transistor; TFT switching characteristics; TFT/LCD electrooptical characteristics; TFT/LCD panel design; amorphous semiconductors; analytical expression; display quality; equivalent electrical circuit; flat panel display; gradual-channel approximation; liquid-crystal color TV; parasitic capacitance; pixel electrode voltage; pixel model; static I-V characteristic; thin film transistor-liquid crystal display panel; Electrodes; Glass; Laboratories; Liquid crystal displays; Parasitic capacitance; Silicon compounds; Substrates; TV; Thin film transistors; Voltage;
Journal_Title :
Electron Devices, IEEE Transactions on
