Makoto Shibusawa

Analysis of dynamic characteristics in a-Si TFT structures

Active-matrix LCDs (liquid crystal displays) addressed by a-Si (amorphous silicon) TFTs (thin-film transistors) are being developed for graphic displays such as computer terminals. Three types of TFTs, a back-channel-etched TFT, a trilayered TFT, and a self-aligned TFT, have been developed. The authors describe the dynamic characteristics of these TFTs, especially level shift in pixel voltage. First, the dependence of the level shift voltage both on drain voltage and on gate pulse delay is demonstrated. The difference of the level shift caused by the TFT structure is then clarified. Then these results are compared to those of SPICE simulation.<<ETX>>

Analysis of dynamic characteristics in a-Si TFT structures (for active-matrix LCD)

Active-matrix LCDs (liquid crystal displays) addressed by a-Si (amorphous silicon) TFTs (thin-film transistors) are being developed for graphic displays such as computer terminals. Three types of TFTs, a back-channel-etched TFT, a trilayered TFT, and a self-aligned TFT, have been developed. The authors describe the dynamic characteristics of these TFTs, especially level shift in pixel voltage. First, the dependence of the level shift voltage both on drain voltage and on gate pulse delay is demonstrated. The difference of the level shift caused by the TFT structure is then clarified. Then these results are compared to those of SPICE simulation. >

A completely self-aligned TFT-array process using five masks

Abstract— In this paper we present a five-mask process to make completely self-aligned inverted-staggered amorphous-silicon TFTs. The mask-count reduction from a conventional seven-mask process was accomplished by simultaneous patterning of pixel electrodes and signal lines and by the use of back-side laser annealing. A mobility value close to 1 cm2/V-s was obtained for TFTs fabricated using this process.