Method of detaching a disc-shaped single crystal from a base body using an electron beam

摘要

The method for detaching a disc-shaped monocrystal from a base body (1), is claimed. The base body has a planar surface (5) in a region in which the disc-shaped monocrystal is intended to be detached. An initial gap (3) is made on one side (2) of the base body. A centre line of the initial gap is located at a distance from the planar surface of the base body, and runs parallel to the planar surface of the base body. The distance corresponds to the disc thickness of the disc-shaped monocrystal to be detached. The surface is scanned in a linear manner using a focused electron beam (6). The method for detaching a disc-shaped monocrystal from a base body (1), is claimed. The base body has a planar surface (5) in a region in which the disc-shaped monocrystal is intended to be detached. An initial gap (3) is made on one side (2) of the base body. A centre line of the initial gap is located at a distance from the planar surface of the base body, and runs parallel to the planar surface of the base body. The distance corresponds to the disc thickness of the disc-shaped monocrystal to be detached. The surface is scanned in a linear manner using a focused electron beam (6), where the scanning starts on the side of the base body on which the initial gap is made and ends on the opposite side of the base body. An acceleration voltage, an electric current and the deflection of the electron beam are adjusted so that required input energy of detaching process of electron beam at a depth of the base body is equal to the disc thickness of the disc-shaped single crystal. The electron beam is formed using an electron-line source formed with a linear focus and an electron beam-point source with highly focused, point-shaped focus, and is introduced at a feed rate normal to a length dimension of the electron beam line over the planar surface of the base body. The centre line of the initial gap is introduced on the side of the base body by a direct patterning method using a laser and an etching method using an ion beam or electron-beam. The base body comprises a monocrystalline substrate and a monocrystalline layer.