Abstract: The present invention relates to a semiconductor chip manufacturing method in which a semiconductor thin film can be cut in a relatively short time and the cut surface can be relatively smoothly formed. When an Si substrate having a diamond thin film formed on the surface thereof is cut in the chip form, a modified region based on multiphoton absorption is formed as a cutting starting point region formed along a cutting planned line by irradiating at least the Si substrate with a laser beam whose condense point is focused to the inside of the Si substrate, along the cutting planned line. The diamond thin film is cut in connection with the cutting of the Si substrate along the cutting starting point region defined by the modified region.

Abstract: A method for fabricating a semiconductor substrate includes epitaxially growing an elemental semiconductor layer on a compound semiconductor substrate. An insulating layer is deposited on top of the elemental semiconductor layer, so as to form a first substrate. The first substrate is wafer bonded onto a monocrystalline Si substrate, such that the insulating layer bonds with the monocrystalline Si substrate. A semiconductor device includes a monocrystalline substrate, and a dielectric layer formed on the monocrystalline substrate. A semiconductor compound is formed on the dielectric layer and an elemental semiconductor material formed in proximity of the semiconductor compound and lattice-matched to the semiconductor compound.