A method of producing a composite structure comprising a thin layer of monocrystalline silicon carbide arranged on a carrier substrate of silicon carbide comprises: a) a step of provision of an initial substrate of monocrystalline silicon carbide, b) a step of epitaxial growth of a donor layer of monocrystalline silicon carbide on the initial substrate, to form a donor substrate, c) a step of ion implantation of light species into the donor layer, to form a buried brittle plane delimiting the thin layer, d) a step of formation of a carrier substrate of silicon carbide on the free surface of the donor layer, comprising a deposition at a temperature of between 400° C. and 1100° C., e) a step of separation along the buried brittle plane, to form the composite structure and the remainder of the donor substrate, and f) a step of chemical-mechanical treatment(s) of the composite structure.

A method of producing a composite structure comprising a thin layer of monocrystalline silicon carbide arranged on a carrier substrate of silicon carbide comprises: a) a step of provision of an initial substrate of monocrystalline silicon carbide, b) a step of epitaxial growth of a donor layer of monocrystalline silicon carbide on the initial substrate, to form a donor substrate, c) a step of ion implantation of light species into the donor layer, to form a buried brittle plane delimiting the thin layer, d) a step of formation of a carrier substrate of silicon carbide on the free surface of the donor layer, comprising a deposition at a temperature of between 400° C. and 1100° C., e) a step of separation along the buried brittle plane, to form the composite structure and the remainder of the donor substrate, and f) a step of chemical-mechanical treatment(s) of the composite structure.

A substrate for group-III nitride epitaxial growth and a method for producing the same is capable of fabricating a high-quality group III nitride single crystal at low cost. 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 consisting of a single crystal with a thickness of between 0.1 μm and 1.5 μm, inclusive, provided on an upper surface planarizing layer and having an uneven pattern on the surface.

A substrate for group-III nitride epitaxial growth and a method for producing the same is capable of fabricating a high-quality group III nitride single crystal at low cost. 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 consisting of a single crystal with a thickness of between 0.1 μm and 1.5 μm, inclusive, provided on an upper surface planarizing layer and having an uneven pattern on the surface.

A wavelength conversion element manufacturing method capable of realizing, in a wavelength conversion element having a structure in which a thin film substrate having a periodic polarization inversion structure and a support substrate are laminated, highly efficient wavelength conversion by confining light in a cross-sectional area smaller than in the known art. The manufacturing method includes steps of forming a periodic polarization inversion structure on a first substrate made of a second-order nonlinear optical crystal and forming a damage layer in the first substrate by implanting ions from one substrate surface to obtain a first substrate for bonding, directly bonding a second substrate having a bonding surface having a smaller refractive index than the first substrate to the one substrate surface of the first substrate at the bonding surface, and peeling the first substrate directly bonded to the second substrate being the support substrate with the damage layer as a boundary to remove a part of the first substrate.

A wavelength conversion element manufacturing method capable of realizing, in a wavelength conversion element having a structure in which a thin film substrate having a periodic polarization inversion structure and a support substrate are laminated, highly efficient wavelength conversion by confining light in a cross-sectional area smaller than in the known art. The manufacturing method includes steps of forming a periodic polarization inversion structure on a first substrate made of a second-order nonlinear optical crystal and forming a damage layer in the first substrate by implanting ions from one substrate surface to obtain a first substrate for bonding, directly bonding a second substrate having a bonding surface having a smaller refractive index than the first substrate to the one substrate surface of the first substrate at the bonding surface, and peeling the first substrate directly bonded to the second substrate being the support substrate with the damage layer as a boundary to remove a part of the first substrate.

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.

A method of producing an epitaxial silicon wafer includes irradiating a surface of a silicon wafer with a beam of cluster ions containing SiH.sub.x ions (at least one of the integers 1 to 3 is selected as x of the SiH.sub.x ions) and C.sub.2H.sub.y ions (at least one of the integers 2 to 5 is selected as y of the C.sub.2H.sub.y ions) to form a modified layer that is located in a surface layer portion of the silicon wafer and that contains as a solid solution of the constituent elements of the cluster ion beam, and further includes forming a silicon epitaxial layer on the modified layer of the silicon wafer. The dose of the SiH.sub.x ions is 1.5×10.sup.14 ions/cm.sup.2 or more.

A method of producing an epitaxial silicon wafer includes irradiating a surface of a silicon wafer with a beam of cluster ions containing SiH.sub.x ions (at least one of the integers 1 to 3 is selected as x of the SiH.sub.x ions) and C.sub.2H.sub.y ions (at least one of the integers 2 to 5 is selected as y of the C.sub.2H.sub.y ions) to form a modified layer that is located in a surface layer portion of the silicon wafer and that contains as a solid solution of the constituent elements of the cluster ion beam, and further includes forming a silicon epitaxial layer on the modified layer of the silicon wafer. The dose of the SiH.sub.x ions is 1.5×10.sup.14 ions/cm.sup.2 or more.

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.