Patent ID: 9601601
Date: 2017-03-21
CPC Classifications: H01L

Claim:
1. A method for manufacturing a semiconductor device comprising the steps of: forming a source electrode and a drain electrode over a substrate; forming an oxide semiconductor layer over the substrate; forming a layer over the oxide semiconductor layer; etching the layer selectively so as to leave a part of the layer overlapping with a source region and a drain region of the oxide semiconductor layer, and so as to expose a channel formation region of the oxide semiconductor layer; and performing an oxidizing treatment to the oxide semiconductor layer having the channel formation region exposed and the source region and the drain region overlapped with the part of the layer so as to desorb hydrogen from the channel formation region of the oxide semiconductor layer, wherein the channel formation region after performing the oxidizing treatment includes hydrogen at a lower concentration than the source region and the drain region, and wherein the layer comprises any one of silicon nitride, silicon nitride oxide, silicon oxynitride, aluminum oxide, aluminum nitride, aluminum oxynitride, titanium oxide, tantalum oxide, and tantalum nitride.