Method for manufacturing semiconductor device

Abstract

A method for manufacturing a semiconductor device includes depositing a first metal oxide film with aluminum as a major component on a substrate, depositing an amorphous oxide semiconductor film on the first metal oxide film under an oxygen partial pressure of 3% to 5%, processing the oxide semiconductor film into a patterned oxide semiconductor layer, crystallizing the oxide semiconductor layer by performing a first heat treatment on the patterned oxide semiconductor layer, processing the first metal oxide film using the crystallized oxide semiconductor layer as a mask, depositing a gate insulating film on the oxide semiconductor layer, and forming a gate electrode on the gate insulating film, wherein a thickness of the oxide semiconductor film is more than 10 nm and 30 nm or less.

Dependencies are inferred from the claim text.