Thin film transistor array substrate, its manufacturing method, and liquid crystal display device

Abstract

In accordance with an exemplary aspect of the present invention, a thin film transistor array substrate includes a transparent insulating substrate, and a thin film transistor for pixel switching and a thin film transistor for a drive circuit formed on the transparent insulating substrate, wherein the thin film transistor for a drive circuit includes an amorphous silicon film formed on the transparent insulating film, a microcrystalline silicon film formed on the amorphous silicon film, a first source electrode and a first drain electrode formed on the microcrystalline silicon film, the first source electrode and the first drain electrode being opposed with a first channel area interposed therebetween, a protective insulating film that covers the first source electrode and the first drain electrode, and an upper gate electrode formed so as to be opposed to the first channel area with the protective insulating film interposed therebetween.

Dependencies are inferred from the claim text.