OXIDE SEMICONDUCTOR, THIN FILM TRANSISTOR, AND THEIR PRODUCTION METHODS

摘要

Disclosed is an oxide semiconductor 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, and a method for producing the thin film transistor. Specifically disclosed is an oxide semiconductor which is characterized by being composed of an amorphous oxide represented by the following general formula: In_x+1MZn_y+1Sn_ZO_{(4+1.5x+y+2z)} (wherein M is Ga or Al, 0 = x = 1, -0.2 = y = 1.2, z = 0.4 and 0.5 = (x + y)/z = 3). This oxide semiconductor 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.