After separation layers are formed inside a single-crystal silicon ingot, a single-crystal silicon substrate is split off from the single-crystal silicon ingot with use of these separation layers as the point of origin. This can improve the productivity of the single-crystal silicon substrate compared with the case of manufacturing the single-crystal silicon substrate from the single-crystal silicon ingot by a wire saw.

The present invention is a substrate for an electronic device, including a nitride semiconductor film formed on a joined substrate including a silicon single crystal, where the joined substrate has at least a bond wafer including a silicon single crystal joined on a base wafer including a silicon single crystal, the base wafer includes CZ silicon having a resistivity of 0.1 Ωcm or lower and a crystal orientation of <100>, and the bond wafer has a crystal orientation of <111>. This provides a substrate for an electronic device, having a suppressed warp.

A single crystal multilayer low-loss optical component including first and second layers made from dissimilar materials, with the materials including the first layer lattice-matched to the materials including the second layer. The first and second layers are grown epitaxially in pairs on a growth substrate to which the materials of the first layer are also lattice-matched, such that a single crystal multilayer optical component is formed. The optical component may further include a second substrate to which the layer pairs are wafer bonded after being removed from the growth substrate.

A method for producing a crystalline oxide semiconductor film in which, a crystalline oxide semiconductor layer and a light absorbing layer are laminated on a substrate, the light absorbing layer is irradiated with light to decompose the light absorbing layer and separate the crystalline oxide semiconductor layer and the substrate to produce a crystalline oxide semiconductor film. This provides a method for industrially advantageously producing a crystalline oxide semiconductor film, for example, a crystalline oxide semiconductor film useful for a semiconductor device (particularly a vertical element).

Provided is a polycrystalline SiC molded body wherein the resistivity is not more than 0.050 Ωcm and, when the peak strength in a wave number range of 760-780 cm.sup.−1 in a Raman spectrum is regarded as “A” and the peak strength in a wave number range of 790-800 cm.sup.−1 in the Raman spectrum is regarded as “B”, then the peak ratio (A/B) is not more than 0.100.

Provided is a polycrystalline SiC molded body wherein the resistivity is not more than 0.050 Ωcm and, when the peak strength in a wave number range of 760-780 cm.sup.−1 in a Raman spectrum is regarded as “A” and the peak strength in a wave number range of 790-800 cm.sup.−1 in the Raman spectrum is regarded as “B”, then the peak ratio (A/B) is not more than 0.100.

Provided is a preparation method for an ultrahigh-conductivity multilayer single-crystal laminated copper material, where multiple layers of single-crystal copper foils are laminated together to form a laminate, and the laminate is pressurized and annealed as one piece by performing pressurizing and high-temperature annealing at the same time, or the laminate is pressed as one piece by means of direct hot rolling, thereby obtaining an ultrahigh-conductivity multi-layer single-crystal laminated copper material, whereby, according to the method, multiple layers of single-crystal copper foils are used as raw materials, an ultrahigh-conductivity multi-layer single-crystal laminated copper material is prepared by means of hot rolling or pressing and annealing, and the conductivity of the copper material is greater than or equal to 105% IACS.

The present invention includes: transferring a C-plane sapphire thin film 1t having an off-angle of 0.5-5° onto a handle substrate composed of a ceramic material having a coefficient of thermal expansion at 800 K that is greater than that of silicon and less than that of C-plane sapphire; performing high-temperature nitriding treatment on the GaN epitaxial growth substrate 11 and covering the surface of the C-plane sapphire thin film 1t with a surface treatment layer 11a made of AlN; having GaN grow epitaxially on the surface treatment layer 11a; ion-implanting a GaN film 13; pasting and bonding together the GaN film-side surface of the ion-implanted GaN film carrier and a support substrate 12; performing peeling at an ion implantation region 13.sub.ion in the GaN film 13 and transferring a GaN thin film 13a onto the support substrate 12; and obtaining a GaN laminate substrate 10.

The present invention includes: transferring a C-plane sapphire thin film 1t having an off-angle of 0.5-5° onto a handle substrate composed of a ceramic material having a coefficient of thermal expansion at 800 K that is greater than that of silicon and less than that of C-plane sapphire; performing high-temperature nitriding treatment on the GaN epitaxial growth substrate 11 and covering the surface of the C-plane sapphire thin film 1t with a surface treatment layer 11a made of AlN; having GaN grow epitaxially on the surface treatment layer 11a; ion-implanting a GaN film 13; pasting and bonding together the GaN film-side surface of the ion-implanted GaN film carrier and a support substrate 12; performing peeling at an ion implantation region 13.sub.ion in the GaN film 13 and transferring a GaN thin film 13a onto the support substrate 12; and obtaining a GaN laminate substrate 10.

The present disclosure relates to the field of manufacturing of silicon carbide (SiC) single crystal wafers, and discloses a stripping method and a stripping device for SiC single crystal wafers. The single crystal wafers obtained by the present disclosure have no damage layer or stress residue on surfaces or sub-surfaces, and are simple in operation and low in cost.