| 摘要 |
<P>PROBLEM TO BE SOLVED: To manufacture a semiconductor device with normally-off characteristics, little variation in electric characteristics, and high reliability in an oxide semiconductor-based transistor. <P>SOLUTION: A first heat treatment is performed for a substrate. Next, an undercoat insulator layer is formed on the substrate. Then, an oxide semiconductor layer is formed on the undercoat insulator layer. There is no exposure to the atmosphere from the first heat treatment through the oxide semiconductor layer formation. After the oxide semiconductor layer is formed, a second heat treatment is performed. The used undercoat insulator layer is made of an insulator layer which releases oxygen by heating. <P>COPYRIGHT: (C)2012,JPO&INPIT |
