Patent ID: 8586406

Claim:
A method for forming an oxide thin film transistor, comprising the following steps: providing a substrate; forming a gate electrode on the substrate; forming a semiconductor insulation layer on the gate electrode; forming a metal oxide layer on the semiconductor insulation layer; forming a first patterned photo-resist layer on the metal oxide layer, wherein the first patterned photo-resist layer is formed by a gray-level mask; using the first patterned photo-resist layer as a mask to etch the metal oxide layer to form a patterned metal oxide layer; removing a part of the first patterned photo-resist layer to form a second patterned photo-resist layer; forming a metal layer on the semiconductor insulation layer, the patterned metal oxide layer, and the second patterned photo-resist layer; forming a third patterned photo-resist layer on the metal layer; using the third patterned photo-resist layer as a mask to etch the metal layer to form a source region and a drain region and to expose the second patterned photo-resist layer; and removing the third patterned photo-resist layer and a part of the second patterned photo-resist layer to form a fourth patterned photo-resist layer.