Thin film transistor and its production method

摘要

Disclosed is an oxide semiconductor (13) having an amorphous structure, wherein higher mobility and reduced carrier concentration are achieved. Also disclosed are a thin film transistor, a method for producing the oxide semiconductor (13), and a method for producing the thin film transistor. Specifically disclosed is an oxide semiconductor (13) which is characterized by being composed of an amorphous oxide represented by general formula: In x+1 MZn y+1 Sn z O (4+1.5x+y+2z) (wherein M=Ga or Al, 0‰¤x‰¤1, -0.2‰¤y‰¤1.2, z‰¥0.4, and 0.5‰¤(x+y)/z‰¤3). This oxide semiconductor (13) is preferably subjected to a heat treatment in an oxidizing gas atmosphere after film formation. Also specifically disclosed is a thin film transistor which is characterized by comprising the oxide semiconductor (13).