摘要 |
<p>A semiconductor device including an oxide semiconductor, which has stable electric characteristics and high reliability, is provided. In a method for manufacturing a transistor including an oxide semiconductor film, an implantation step where rare gas ions are implanted to the oxide semiconductor film is performed, and the oxide semiconductor film to which rare gas ions are implanted is subjected to a heating step under reduced pressure, in a nitrogen atmosphere, or in a rare gas atmosphere, whereby hydrogen or water contained in the oxide semiconductor film to which rare gas ions are implanted is released; thus, the oxide semiconductor film is highly purified.</p> |