Abstract: A second single crystal semiconductor film is formed over a first single crystal semiconductor film; a separation layer is formed by addition of ions into the second single crystal semiconductor film; a second insulating film functioning as a bonding layer is formed over the second single crystal semiconductor film; a surface of a first SOI substrate and a surface of a second substrate are made to face each other, so that a surface of the second insulating film and the surface of the second substrate are bonded to each other; and then heat treatment is performed to cause cleavage at the separation layer, so that a second SOI substrate in which a part of the second single crystal semiconductor film is provided over the second substrate with the second insulating film interposed therebetween is formed.

Abstract: A photoelectric conversion device having an excellent photoelectric conversion characteristic is provided while effectively utilizing limited resources. A fragile layer is formed in a region at a depth of less than 1000 nm from one surface of a single crystal semiconductor substrate, and a first impurity semiconductor layer, a first electrode, and an insulating layer are formed on the one surface side of the single crystal semiconductor substrate. After bonding the insulating layer to a supporting substrate, the single crystal semiconductor substrate is separated with the fragile layer or its vicinity used as a separation plane, thereby forming a first single crystal semiconductor layer over the supporting substrate.