Patent ID: 7767547
Filing Date: 2010-08-03
Classification: H01L

Abstract:
1. A method for manufacturing an SOI substrate comprising the steps of: forming a plurality of first single crystal semiconductor films over a first substrate having an insulating surface with intervals between the plurality of first single crystal semiconductor films; forming a semiconductor film over the plurality of first single crystal semiconductor films; performing planarization treatment on the semiconductor film so as to expose the first single crystal semiconductor films; forming a first insulating film over the first single crystal semiconductor films and the semiconductor film; superposing a plurality of single crystal semiconductor substrates in each of which a first fragile layer is formed at a predetermined depth on the first insulating film such that the semiconductor film is superimposed over the plurality of single crystal semiconductor substrates; forming a plurality of second single crystal semiconductor films over the first insulating film by separation at the first fragile layer through heat treatment; exposing the first single crystal semiconductor films by etching the first insulating film with the second single crystal semiconductor films used as masks; forming a third single crystal semiconductor film over the first substrate using the first single crystal semiconductor films and the second single crystal semiconductor films as seed layers; forming a second fragile layer by introducing ions into the third single crystal semiconductor film; forming a second insulating film which functions as a bonding layer over the third single crystal semiconductor film; and fixing a part of the third single crystal semiconductor film to the second substrate with the second insulating film interposed therebetween by superposing the first substrate on a second substrate having an insulating surface and separating the third single crystal semiconductor film at the second fragile layer through heat treatment.