Patent ID: 6852653

Claim:
A method of manufacturing a semiconductor substrate comprising the processes of: forming an insulation film on at least a surface of a semiconductor substrate main body; forming an ion shield member having a predetermined shape on said insulation film; subsequent to forming the insulation film, implanting ions into said semiconductor substrate main body from a side on which said insulation film is formed, to thereby form an ion implantation layer; removing said ion shield member; cleaning or smoothing the surface of said insulation film; laminating said insulation film and a support substrate onto each other; and separating a portion of said semiconductor substrate main body from said support substrate along said ion implantation layer, wherein a shape of an outer edge of said ion shield member is tapered, and thereby said ion implantation layer is partly inclined in response to said tapered shape of the outer edge of said ion shield member, so as to prevent separation defect in remaining portion of the semiconductor substrate main body on said support substrate.