초록 ▼

A systemized active matrix display in which a pixel matrix circuit, a driver circuit and a logic circuit are mounted on the same substrate, is formed. A TFT of the present invention has such characteristics as to be able to operate in a wide driving frequency range of 0.05 to 2 GHz, and by designing

A systemized active matrix display in which a pixel matrix circuit, a driver circuit and a logic circuit are mounted on the same substrate, is formed. A TFT of the present invention has such characteristics as to be able to operate in a wide driving frequency range of 0.05 to 2 GHz, and by designing a channel length and a film thickness of a gate insulating film of the TFT according to characteristics required by circuits, it is possible to form a high frequency driving circuit and a low frequency driving circuit on the same substrate.

대표청구항 ▼

[ What is claimed is:] [21.] A semiconductor device comprising:a substrate having an insulating surface; anda circuit operated at a frequency of at least 25 MHz, formed over said substrate, said circuit comprising at least one thin film transistor, wherein said thin film transistor comprises a cryst

[ What is claimed is:] [21.] A semiconductor device comprising:a substrate having an insulating surface; anda circuit operated at a frequency of at least 25 MHz, formed over said substrate, said circuit comprising at least one thin film transistor, wherein said thin film transistor comprises a crystalline semiconductor film including a channel region therein, a gate insulating film adjacent to said crystalline semiconductor film and a gate electrode adjacent to said gate insulating film,wherein a thickness of said gate insulating film is not smaller than 1000 .ANG. and a channel length of said thin film transistor is not smaller than 1.5 .mu.m, and a subthreshold coefficient of the thin film transistor is from 60 to 100 mV/decade.