Title :
A new a-Si TFT with SiO2/SiN/sub x/ gate insulator for 10.4-inch LCDs
Author :
Ibaraki, N. ; Shimano, T. ; Fukuda, K. ; Matsumura, K. ; Suzuki, K. ; Toeda, H. ; Takikawa, O.
Author_Institution :
Toshiba Corp., Yokohama, Japan
Abstract :
A novel a-Si TFT (thin-film transistor) with a composite gate insulator of CVD (chemical-vapor-deposited) SiO/sub 2//PE-CVD (plasma-enhanced CVD) SiN/sub x/ has been developed. This TFT has been applied to 10.4-in-diagonal LCDs (liquid crystal displays). Because of the high quality of CVD SiO/sub 2/, Vth drift, which was often observed after prolonged application of gate bias, was remarkably reduced compared to PE-CVD SiO/sub x/N/sub y/. Also, the degradation of subthreshold characteristics on a-Si TFT (often observed after long-term operation of LCDs at high temperature) was improved. Selective etching technologies of SiN/sub x/ against SiO/sub 2/, which is one of key issues in connection with obtaining high production yield, have been developed.<>
Keywords :
amorphous semiconductors; elemental semiconductors; etching; insulated gate field effect transistors; insulating thin films; liquid crystal displays; plasma CVD coatings; semiconductor technology; silicon; silicon compounds; thin film transistors; 10.4 inch; Si-SiO/sub 2/-SiN/sub x/; Vth drift; composite gate insulator; degradation; etching; liquid crystal displays; plasma-enhanced CVD; production yield; subthreshold characteristics; thin-film transistor; Chemical vapor deposition; Degradation; Insulation; Liquid crystal displays; Plasma applications; Plasma chemistry; Plasma displays; Plasma temperature; Silicon compounds; Thin film transistors;
Conference_Titel :
Display Research Conference, 1991., Conference Record of the 1991 International
Conference_Location :
San Diego, CA, USA
Print_ISBN :
0-7803-0213-3
DOI :
10.1109/DISPL.1991.167485
