초록 ▼

A semiconductor integrated circuit having a high withstand voltage TFT and a TFT which is capable of operating at high speed in a circuit of thin film transistors (TFT) and methods for fabricating such circuit will be provided. A gate insulating film of the TFT required to operate at high speed (e.g

A semiconductor integrated circuit having a high withstand voltage TFT and a TFT which is capable of operating at high speed in a circuit of thin film transistors (TFT) and methods for fabricating such circuit will be provided. A gate insulating film of the TFT required to operate at high speed (e.g., TFT used for a logic circuit) is relatively thinned less than a gate insulating film of the TFT which is required to have high withstand voltage (e.g., TFT used for switching high voltage signals).

대표청구항 ▼

[ What is claimed is:] [1.]1. A semiconductor device having a driving circuit and an active matrix circuit, said driving circuit comprising:a logic circuit having at least a first thin film transistor formed over a substrate, said first thin film transistor having a first gate insulating film and a

[ What is claimed is:] [1.]1. A semiconductor device having a driving circuit and an active matrix circuit, said driving circuit comprising:a logic circuit having at least a first thin film transistor formed over a substrate, said first thin film transistor having a first gate insulating film and a first gate electrode;a buffer circuit having at least a second thin film transistor formed over said substrate, said second thin film transistor having a second gate insulating film and a second gate electrode; anda high withstand voltage switching circuit having at least a third thin film transistor formed over said substrate, said third thin film transistor having a third gate insulating film and a third gate electrode,wherein each width of said second and third gate electrodes is larger than the width of said first gate electrode,wherein a thickness of said first gate insulating film is 80% or less of each thickness of said second and third gate insulating films.