Provided is a crystal laminate including: a crystal substrate formed from a monocrystal of group III nitride expressed by a compositional formula In.sub.xAl.sub.yGa.sub.1-x-yN (where 0≤x≤1, 0≤y≤1, 0≤x+y≤1), the crystal substrate containing at least any one of n-type impurity selected from the group consisting of Si, Ge, and O; and a crystal layer formed by a group III nitride crystal epitaxially grown on a main surface of the crystal substrate, at least any one of p-type impurity selected from the group consisting of C, Mg, Fe, Be, Zn, V, and Sb being ion-implanted in the crystal layer. The crystal laminate is configured in a manner such that an absorption coefficient of the crystal substrate for light with a wavelength of 2000 nm when the crystal substrate is irradiated with the light falls within a range of 1.8 cm.sup.−1 or more and 4.6 cm.sup.−1 or less under a temperature condition of normal temperature.

A synthetic diamond material comprises a surface, wherein the surface comprises a first surface region comprising a first concentration of quantum spin defects. A second surface region has a predetermined area and is located adjacent to the first surface region, the second region comprising a second concentration of quantum spin defects. The first concentration of quantum spin defects is at least ten times greater than the second concentration of quantum spin defects, and at least one of the first or second surface regions comprises chemical vapour deposition, CVD, synthetic diamond. A method of producing the synthetic diamond material is also disclosed.

A substrate for group III nitride epitaxial growth and a method for producing the same. The substrate for group III nitride epitaxial growth includes: a supporting substrate having a structure in which a core consisting of nitride ceramics is wrapped in an encapsulating layer having a thickness of between 0.05 μm and 1.5 μm, inclusive; a planarizing layer provided on an upper surface of the supporting substrate, the planarizing layer having a thickness of between 0.5 μm and 3.0 μm, inclusive; and a seed crystal layer made of a single crystal of a group III nitride, the seed crystal layer being provided on an upper surface of the planarizing layer and having a thickness of between 0.1 μm and 1.5 μm, inclusive.

A substrate for group III nitride epitaxial growth and a method for producing the same. The substrate for group III nitride epitaxial growth includes: a supporting substrate having a structure in which a core consisting of nitride ceramics is wrapped in an encapsulating layer having a thickness of between 0.05 μm and 1.5 μm, inclusive; a planarizing layer provided on an upper surface of the supporting substrate, the planarizing layer having a thickness of between 0.5 μm and 3.0 μm, inclusive; and a seed crystal layer made of a single crystal of a group III nitride, the seed crystal layer being provided on an upper surface of the planarizing layer and having a thickness of between 0.1 μm and 1.5 μm, inclusive.

Methods are provided for separating a crystalline film from its main body. The method uses ion implantation to generate an ion damaged layer underneath the surface of the crystalline object. The ion damage changes the crystal structure of the ion damaged layer, so it will have different optical transmittance and absorption characteristics from the undamaged part of the crystalline object. A laser beam with a wavelength that is higher than the absorption edge of the non-ion damaged material, but within the absorption range of the ion damaged material is irradiated at or past the ion damaged layer, causing further damage to the ion damaged layer. The film can then be separated from the main body of the crystalline object.

Methods are provided for separating a crystalline film from its main body. The method uses ion implantation to generate an ion damaged layer underneath the surface of the crystalline object. The ion damage changes the crystal structure of the ion damaged layer, so it will have different optical transmittance and absorption characteristics from the undamaged part of the crystalline object. A laser beam with a wavelength that is higher than the absorption edge of the non-ion damaged material, but within the absorption range of the ion damaged material is irradiated at or past the ion damaged layer, causing further damage to the ion damaged layer. The film can then be separated from the main body of the crystalline object.

A method for structuring a decorative or technical pattern in the thickness of an object made of an at least partially transparent amorphous, semi-crystalline or crystalline material, wherein the object is made of an at least partially transparent material including a top surface and a bottom surface which extends away from the top surface. The top or bottom surfaces is provided with a mask defining an opening whose outline corresponds to the profile of the pattern to be structured, the mask covering the top or bottom surface at the positions which are not to be structured. The pattern is structured with a mono- or multicharged ion beam through the opening of the mask, wherein the mechanical properties of the mask are sufficient to prevent the ions of the ion beam from etching the top or bottom surface at the positions where this top or bottom surface is covered by the mask.

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.

In this method for manufacturing a semiconductor element, a modified layer produced by subjecting a substrate (70) to mechanical polishing is removed by heating the substrate (70) under Si vapor pressure. An epitaxial layer formation step, an ion implantation step, an ion activation step, and a second removal step are then performed. In the second removal step, macro-step bunching and insufficient ion-implanted portions of the surface of the substrate (70) performed the ion activation step are removed by heating the substrate (70) under Si vapor pressure. After that, an electrode formation step in which electrodes are formed on the substrate (70) is performed.