In the case where an integrated circuit formed of a thin film is formed
over a substrate and peeled from the substrate, a fissure (also referred
to as crack) is generated in the integrated circuit in some cases. The
present invention is to restrain the generation of a fissure by fixing
the proceeding direction of etching in one direction to make a peeled
layer warp in one direction in accordance with the proceeding of etching.
For example, the proceeding of etching can be controlled by utilizing the
fact that a portion where a substrate is in contact with a base
insulating layer is not etched in the case of patterning a peeling layer
provided over the substrate, then forming the base insulating layer, and
then fixing a peeled layer by the portion where the substrate is in
contact with the base insulating layer.