A system for labeling an object uses at least one object label made from a material that absorbs and reflects incident energy uniformly across all wavelengths of incident energy at a ratio proportional to a thickness of the material and that includes a pattern having variations in the thickness of the material along at least one of two orthogonal directions across the label. An interrogator directs a predetermined wavelength of radiation to the at least one label, and a reader to receives reflected radiation from the label at the predetermined wavelength and interprets the reflected radiation to recognize the pattern.

A system for labeling an object uses at least one object label made from a material that absorbs and reflects incident energy uniformly across all wavelengths of incident energy at a ratio proportional to a thickness of the material and that includes a pattern having variations in the thickness of the material along at least one of two orthogonal directions across the label. An interrogator directs a predetermined wavelength of radiation to the at least one label, and a reader to receives reflected radiation from the label at the predetermined wavelength and interprets the reflected radiation to recognize the pattern.

A composite substrate includes a sapphire substrate and a layer of a nitride of a group 13 element provided on the sapphire substrate. The layer of the nitride of the group 13 element is composed of gallium nitride, aluminum nitride or gallium aluminum nitride. The composite substrate satisfies the following formulas (1), (2) and (3). A laser light is irradiated to the composite substrate from the side of the sapphire substrate to decompose crystal lattice structure at an interface between the sapphire substrate and the layer of the nitride of the group 13 element. 5.0≦(an average thickness (μm) of the layer of the nitride of the group 13 element/a diameter (mm) of the sapphire substrate)≦10.0 . . . (1); 0.1≦ a warpage (mm) of said composite substrate×(50/a diameter (mm) of said composite substrate).sup.20.6 . . . (2); 1.10≦a maximum value (μm) of a thickness of said layer of said nitride of said group 13 element/a minimum value (μm) of said thickness of said layer of said nitride of said group 13 element . . . (3)

A silicon carbide single crystal substrate includes a first main surface, a second main surface, and a circumferential edge portion. The second main surface is opposite to the first main surface. The circumferential edge portion connects the first main surface and the second main surface. The circumferential edge portion has a linear orientation flat portion, a first arc portion having a first radius, and a second arc portion connecting the orientation flat portion and the first arc portion and having a second radius smaller than the first radius, when viewed along a direction perpendicular to the first main surface.

A silicon carbide single crystal substrate includes a first main surface, a second main surface, and a circumferential edge portion. The second main surface is opposite to the first main surface. The circumferential edge portion connects the first main surface and the second main surface. The circumferential edge portion has a linear orientation flat portion, a first arc portion having a first radius, and a second arc portion connecting the orientation flat portion and the first arc portion and having a second radius smaller than the first radius, when viewed along a direction perpendicular to the first main surface.

A germanium single-crystal wafer comprises silicon with an atomic concentration of from 3×10.sup.14 atoms/cc to 10×10.sup.13 atoms/cc, boron with an atomic concentration of from 1×10.sup.16 atoms/cc to 10×10.sup.18 atoms/cc, and gallium with an atomic concentration of from 1×10.sup.16 atoms/cc to 10×10.sup.19 atoms/cc. Further provided are a method for preparing the germanium single-crystal wafer, a method for preparing a germanium single-crystal ingot, and the use of the germanium single-crystal wafer for increasing the open-circuit voltage of a solar cell. The germanium single-crystal wafer has an improved electrical property in that it has a smaller difference in resistivity and carrier concentration.

An ultra-hard carbon film is formed by the uniaxial compression of thin films of graphene. The graphene films are two or three layers thick (2-L or 3-L). High pressure compression forms a diamond-like film and provides improved properties to the coated substrates.

An ultra-hard carbon film is formed by the uniaxial compression of thin films of graphene. The graphene films are two or three layers thick (2-L or 3-L). High pressure compression forms a diamond-like film and provides improved properties to the coated substrates.

The present invention relates to a method for manufacturing a semiconductor substrate, including: (a) preparing an epitaxial substrate having a nitride semiconductor layer formed on a first main surface of a growth substrate and preparing a first support substrate, forming a resin adhesive layer between the first main surface of the growth substrate and a first main surface of the first support substrate, and bonding the epitaxial substrate to the first support substrate; (b) thinning a second main surface of the growth substrate; (c) forming a first protective thin film layer on the thinned growth substrate; (d) forming a second protective thin film layer on the first support substrate; (e) removing the thinned growth substrate; (0 bonding a second support substrate onto the nitride semiconductor layer; and (g) removing the first support substrate and the resin adhesive layer.

The present invention relates to a method for manufacturing a semiconductor substrate, including: (a) preparing an epitaxial substrate having a nitride semiconductor layer formed on a first main surface of a growth substrate and preparing a first support substrate, forming a resin adhesive layer between the first main surface of the growth substrate and a first main surface of the first support substrate, and bonding the epitaxial substrate to the first support substrate; (b) thinning a second main surface of the growth substrate; (c) forming a first protective thin film layer on the thinned growth substrate; (d) forming a second protective thin film layer on the first support substrate; (e) removing the thinned growth substrate; (0 bonding a second support substrate onto the nitride semiconductor layer; and (g) removing the first support substrate and the resin adhesive layer.