A semiconductor stack includes a substrate made of silicon carbide, and an epi layer disposed on the substrate and made of silicon carbide. An epi principal surface, which is a principal surface opposite to the substrate, of the epi layer is a carbon surface having an off angle of 4 or smaller relative to a c-plane. In the epi principal surface, a plurality of first recessed portions having a rectangular circumferential shape in a planar view is famed. Density of a second recessed portion that is formed in the first recessed portions and is a recessed portion deeper than the first recessed portions is lower than or equal to 10 cm.sup.2 in the epi principal surface.

A method of manufacturing graphene, the method including: preparing a carrier member on which the graphene is formed on one surface thereof; exposing the graphene to dopant vapor to dope the graphene; transferring the doped graphene onto a target member; and removing the carrier member.

A -Ga.sub.2O.sub.3-based single-crystal substrate includes a -Ga.sub.2O.sub.3-based single crystal, and a principal surface being a plane parallel to a b-axis of the -Ga.sub.2O.sub.3-based single crystal. A maximum value of on an arbitrary straight line on the principal surface that passes through a center of the principal surface is not more than 0.7264. The is a difference between a maximum value and a minimum value of values obtained by subtracting .sub.a from .sub.s at each of measurement positions, where .sub.s represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and .sub.a represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the .sub.s and the measurement positions thereof.

A fluorescent member includes: a wavelength converter including an incidence part on which a light of a light source is incident and an output part from which a converted light subjected to wavelength conversion as a result of excitation by an incident light is output; and a reflecting part provided in at least a portion of a surface of the wavelength converter. The wavelength converter is comprised of a material whereby a degree of scattering of the light of the light source incident via the incidence part and traveling toward the output part is smaller than in the case of a polycrystalline material.

A silicon carbide single crystal substrate includes a first main surface and an orientation flat. The orientation flat extends in a <11-20> direction. The first main surface includes an end region extending by at most 5 mm from an outer periphery of the first main surface. In a direction perpendicular to the first main surface, an amount of warpage of the end region continuous to the orientation flat is not greater than 3 m.

Some variations provide a method of making an additively manufactured single-crystal metallic component, comprising: providing a feedstock comprising a first metal or metal alloy; providing a build plate comprising a single crystal of a second metal or metal alloy; exposing the feedstock to an energy source for melting the feedstock, generating a melt layer on the build plate; and solidifying the melt layer, generating a solid layer (on the build plate) of a metal component. The solid layer is also a single crystal of the first metal or metal alloy. The method may be repeated many times to build the part. Some variations provide a single-crystal metallic component comprising a plurality of solid layers in an additive-manufacturing build direction, wherein the plurality of solid layers forms a single crystal of a metal or metal alloy with a continuous crystallographic texture. The crystal orientation may vary along the additive-manufacturing build direction.

Some variations provide a method of making an additively manufactured single-crystal metallic component, comprising: providing a feedstock comprising a first metal or metal alloy; providing a build plate comprising a single crystal of a second metal or metal alloy; exposing the feedstock to an energy source for melting the feedstock, generating a melt layer on the build plate; and solidifying the melt layer, generating a solid layer (on the build plate) of a metal component. The solid layer is also a single crystal of the first metal or metal alloy. The method may be repeated many times to build the part. Some variations provide a single-crystal metallic component comprising a plurality of solid layers in an additive-manufacturing build direction, wherein the plurality of solid layers forms a single crystal of a metal or metal alloy with a continuous crystallographic texture. The crystal orientation may vary along the additive-manufacturing build direction.

Embodiments described herein provide processes for forming and removing epitaxial films and materials from growth wafers by epitaxial lift off (ELO) processes. In some embodiments, the growth wafer has edge surfaces with an off-axis orientation which is utilized during the ELO process. The off-axis orientation of the edge surface provides an additional variable for controlling the etch rate during the ELO process and therefore the etch front may be modulated to prevent the formation of high stress points which reduces or prevents stressing and cracking the epitaxial film stack. In one embodiment, the growth wafer is rectangular and has an edge surface with an off-axis orientation rotated by an angle greater than 0 and up to 90 relative to an edge orientation of <110> at 0.

Embodiments described herein provide processes for forming and removing epitaxial films and materials from growth wafers by epitaxial lift off (ELO) processes. In some embodiments, the growth wafer has edge surfaces with an off-axis orientation which is utilized during the ELO process. The off-axis orientation of the edge surface provides an additional variable for controlling the etch rate during the ELO process- and therefore the etch front may be modulated to prevent the formation of high stress points which reduces or prevents stressing and cracking the epitaxial film stack. In one embodiment, the growth wafer is rectangular and has an edge surface with an off-axis orientation rotated by an angle greater than 0 and up to 90 relative to an edge orientation of <110> at 0.

Embodiments described herein provide processes for forming and removing epitaxial films and materials from growth wafers by epitaxial lift off (ELO) processes. In some embodiments, the growth wafer has edge surfaces with an off-axis orientation which is utilized during the ELO process. The off-axis orientation of the edge surface provides an additional variable for controlling the etch rate during the ELO process and therefore the etch front may be modulated to prevent the formation of high stress points which reduces or prevents stressing and cracking the epitaxial film stack. In one embodiment, the growth wafer is rectangular and has an edge surface with an off-axis orientation rotated by an angle greater than 0 and up to 90 relative to an edge orientation of <110> at 0.