| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for forming regions with different conductivity in an arbitrary region of an oxide semiconductor layer in a transistor having the oxide semiconductor layer.SOLUTION: A hydrogen barrier layer is selectively provided over an oxide semiconductor layer including hydrogen, and hydrogen is selectively desorbed from a predetermined region of the oxide semiconductor layer by conducting oxidation treatment, so that regions with different conductivity are formed in the oxide semiconductor layer. Then, a channel formation region, a source region, and a drain region can be formed by using the regions with different conductivity formed in the oxide semiconductor layer. |
