| 摘要 |
A hydrogen barrier layer is selectively provided over an oxide semiconductor layer including hydrogen and hydrogen is selectively desorbed from a given region in the oxide semiconductor layer by conducting oxidation treatment, so that regions with different conductivities are formed in the oxide semiconductor layer. After that, a channel formation region, a source region, and a drain region can be formed with the use of the regions with different conductivities formed in the oxide semiconductor layer. |
