摘要 |
PURPOSE:To enable the gate insulating film to be made of a thin film by providing the gate insulating film between the active layer forming a channel and the gate electrode with a double-layer structure of the thermal oxide film of the active layer and a silicon oxide thin film formed on the thermal oxide film, thereby improving the dielectric strength of the gate insulating film. CONSTITUTION:An active layer 5 is comprised of an amorphous silicon thin film, for instance, a hydrogenated amorphous silicon thin film or a polysilicon thin film. The gate insulating film between this active layer 5 and a gate electrode 6 is provided with a double-layer structure of a thermal oxide film 4a of the active layer 5 and a silicon oxide thin film 4b formed on the thermal oxide film 4a. The film thickness of the gate insulating films 4a, 4b of a double- layer structure is preferably 500-2000Angstrom . With this, the dielectric strength of the gate insulating film is enhanced, and it can be made of a thin film, thereby enabling the transistor to operate at a high speed. |