Patent ID: 9673232
Date: 2017-06-06
CPC Classifications: H01L

Claim:
1. A thin-film transistor comprising: a gate electrode, a gate insulating film, and a semiconductor layer stacked in order on a substrate; and a source electrode and a drain electrode arranged separately so as to face each other on said semiconductor layer, wherein said semiconductor layer has two layers including: an oxide semiconductor film stacked on said gate insulating film and made of an oxide semiconductor; and an oxide conductive film stacked on said oxide semiconductor film and made of a conductive oxide, said oxide conductive film being directly over, and contacting with, the upper surface of said oxide semiconductor film at any plane position in said oxide conductive film, said source electrode and said drain electrode are electrically connected to said oxide semiconductor film through said oxide conductive film at least at an end portion of said source electrode and an end portion of said drain electrode facing each other, at said semiconductor layer placed between said source electrode and said drain electrode facing each other, a channel region is formed by said oxide semiconductor film, said oxide semiconductor film has a substantially tapered shape in cross section at an end face thereof, at least one of said source electrode and said drain electrode covers said end face of said oxide semiconductor film, where said end face is substantially tapered, and said at least one of said source electrode and said drain electrode extends to a region outside said oxide semiconductor film when viewed in plan view, and in a region between said end portion of said source electrode and said end portion of said drain electrode facing each other when viewed in plan view, a portion of said oxide conductive film is separated such that a gap exists between said oxide conductive film disposed under said end portion of said source electrode and said oxide conductive film disposed under said end portion of said drain electrode, wherein said gap is filled with a protective insulating film.