A method of manufacturing a semiconductor substrate is demonstrated, which enables the formation of a single crystal semiconductor layer on a substrate having an insulating surface. The manufacturing method includes the steps of: ion irradiation of a surface of a single-crystal semiconductor substrate to form a damaged region; laser light irradiation of the single-crystal semiconductor substrate; formation of an insulating layer on the surface of the single-crystal semiconductor substrate; bonding the insulating layer with a substrate having an insulating surface; separation of the single-crystal semiconductor substrate at the damaged region, resulting in a thin single-crystal semiconductor layer on the surface of the substrate having the insulating surface; and laser light irradiation of the surface of the single-crystal semiconductor layer which is formed on the substrate having the insulating surface. This method allows the production of a thin layer of a single-crystal semiconductor with uniformed characteristics on an insulating surface.