Provided are a composite substrate in which a wafer to be bonded has a sufficiently small surface roughness and which can be prevented from causing film peeling, and a method for producing the composite substrate. The composite substrate 40 of the present invention has a silicon wafer 10, an interlayer 11, and a single-crystal silicon thin film or oxide single-crystal thin film 20a stacked in the order listed and has a damaged layer 12a in a portion of the silicon wafer 10 on the side of the interlayer 11.

A seed crystal layer is provided on a supporting body. A laser light is irradiated from a side of the supporting body to provide an altered portion along an interface between the supporting body and seed crystal layer. The altered layer is composed of a nitride of a group 13 element and comprising a portion into which dislocation defects are introduced or an amorphous portion.

Methods and equipment for the removal of semiconductor wafers grown on the top surface of a single crystal silicon substrate covered by a porous silicon separation layer by using IR irradiation of the porous silicon separation layer to initiate release of the semiconductor wafer from the substrate, particularly at edges (and corners) of the top surface of the substrate.

A method of manufacturing a silicon carbide substrate includes the steps of preparing an ingot of single crystal silicon carbide and obtaining a substrate by cutting the ingot. Then, in the step of obtaining a substrate, cutting proceeds in a direction α in which an angle β formed with respect to a <11-20> direction or a <1-100> direction of the ingot is 15°±5° in an orthogonal projection on a {0001} plane.

A method of manufacturing a silicon carbide substrate includes the steps of preparing an ingot of single crystal silicon carbide and obtaining a substrate by cutting the ingot. Then, in the step of obtaining a substrate, cutting proceeds in a direction α in which an angle β formed with respect to a <11-20> direction or a <1-100> direction of the ingot is 15°±5° in an orthogonal projection on a {0001} plane.

Method for transferring a useful layer onto a supporting substrate, comprising the successive steps: a) providing a donor substrate made of crystalline diamond; b) implanting gaseous species, through the first surface of the donor substrate, according to a given implantation dose and implantation temperature suitable for forming a graphitic flat zone; c) assembling the donor substrate to the supporting substrate by direct adhesion; d) applying thermal annealing according to a thermal budget suitable for fracturing the donor substrate along the graphitic flat zone; the annealing temperature being greater than or equal to 800° C.; the implantation temperature is: above a minimum temperature beyond which bubbling of the implanted gaseous species occurs on the first surface when the donor substrate is submitted, in the absence of a stiffening effect, to thermal annealing according to said thermal budget, below a maximum temperature beyond which the given implantation dose no longer allows formation of the graphitic flat zone.

Method for transferring a useful layer onto a supporting substrate, comprising the successive steps: a) providing a donor substrate made of crystalline diamond; b) implanting gaseous species, through the first surface of the donor substrate, according to a given implantation dose and implantation temperature suitable for forming a graphitic flat zone; c) assembling the donor substrate to the supporting substrate by direct adhesion; d) applying thermal annealing according to a thermal budget suitable for fracturing the donor substrate along the graphitic flat zone; the annealing temperature being greater than or equal to 800° C.; the implantation temperature is: above a minimum temperature beyond which bubbling of the implanted gaseous species occurs on the first surface when the donor substrate is submitted, in the absence of a stiffening effect, to thermal annealing according to said thermal budget, below a maximum temperature beyond which the given implantation dose no longer allows formation of the graphitic flat zone.

A laser processing apparatus for producing a GaN wafer from a GaN ingot includes a laser beam irradiating unit configured to apply a laser beam having a wavelength capable of passing through the GaN ingot held by a chuck table. The laser beam irradiating unit includes a laser oscillator configured to oscillate the laser beam. The laser oscillator includes a seeder configured to oscillate a high-frequency pulsed laser, a thinning-out unit configured to thin out high-frequency pulses oscillated by the seeder at a predetermined repetition frequency, and generate one burst pulse with a plurality of high-frequency pulses as sub-pulses, and an amplifier configured to amplify the generated burst pulse.

A substrate includes a support structure comprising a polycrystalline ceramic core, a first adhesion layer encapsulating the polycrystalline ceramic core, a barrier layer encapsulating the first adhesion layer, a second adhesion layer coupled to the barrier layer, and a conductive layer coupled to the second adhesion layer. The substrate also includes a bonding layer coupled to the support structure, a substantially single crystal silicon layer coupled to the bonding layer, and an epitaxial semiconductor layer coupled to the substantially single crystal silicon layer.

A substrate includes a support structure comprising a polycrystalline ceramic core, a first adhesion layer encapsulating the polycrystalline ceramic core, a barrier layer encapsulating the first adhesion layer, a second adhesion layer coupled to the barrier layer, and a conductive layer coupled to the second adhesion layer. The substrate also includes a bonding layer coupled to the support structure, a substantially single crystal silicon layer coupled to the bonding layer, and an epitaxial semiconductor layer coupled to the substantially single crystal silicon layer.