| 摘要 |
<p>An object is to provide a method for manufacturing an SOI substrate including a semiconductor film with high planarity and high crystallinity. After a single crystal semiconductor film is formed over an insulating film by a separation step, a natural oxide film existing on a surface of the semiconductor film is removed and the semiconductor film is irradiated with first laser light and second laser light under an inert gas atmosphere or a reduced-pressure atmosphere. The number of shots of the first laser light that is emitted to an arbitrary point in the semiconductor film is greater than or equal to 7, preferably greater than or equal to 10 and less than or equal to 100. The number of shots of the second laser light that is emitted to an arbitrary point in the semiconductor film is greater than 0 and less than or equal to 2.</p> |
