A method for obtaining mesas that are made at least in part of a nitride (N), the method includes providing a stack comprising a substrate and at least the following layers disposed in succession from the substrate a first layer, referred to as the flow layer, and a second, crystalline layer, referred to as the crystalline layer; forming pads by etching the crystalline layer and at least one portion of the flow layer such that: —each pad includes at least: —a first section, referred to as the flow section, formed by at least one portion of the flow layer, and a second, crystalline section, referred to as the crystalline section, framed by the crystalline layer and overlying the flow section, the pads are distributed over the substrate so as to form a plurality of sets of pads; and epitaxially growing a crystallite on at least some of said pads and continuing the epitaxial growth of the crystallites until the crystallites carried by the adjacent pads of the same set coalesce.

A III-nitride-based semiconductor wafer is provided that includes a substrate with a central region and a peripheral edge region. One or more intermediate layers may be optionally provided selected from a buffer layer, a seed layer, or a transition layer. A peripheral edge feature is formed in or on a peripheral edge region of the substrate or the transition layer, with one or more peripheral edge passivation layers or peripheral edge surface texturing. The peripheral edge feature extends only around the peripheral edge and not in the central region. One or more III-nitride-based layers is positioned over the central region. In the central region, the III-nitride layer is an epitaxial layer while in the peripheral edge region, it is a polycrystalline layer. Stress due to lattice mismatches and differences in the coefficient of thermal expansion between the III-nitride layer and the substrate is relieved, minimizing defects.

A method of performing heteroepitaxy comprises exposing a substrate to a carrier gas, a first precursor gas, a Group II/III element, and a second precursor gas, to form a heteroepitaxial growth of one of GaAs, AlAs, InAs, GaP, InP, ZnSe, GaSe, CdSe, InSe, ZnTe, CdTe, GaTe, HgTe, GaSb, InSb, AlSb, CdS, GaN, and AlN on the substrate; wherein the substrate comprises one of GaAs, AlAs, InAs, GaP, InP, ZnSe, GaSe, CdSe, InSe, ZnTe, CdTe, GaTe, HgTe, GaSb, InSb, AlSb, CdS, GaN, and AlN; wherein the carrier gas is Hz, wherein the first precursor is HCl, the Group II/III element comprises at least one of Zn, Cd, Hg, Al, Ga, and In; and wherein the second precursor is one of AsH.sub.3 (arsine), PH.sub.3 (phosphine), H.sub.2Se (hydrogen selenide), H.sub.2Te (hydrogen telluride), SbH.sub.3 (hydrogen antimonide), H.sub.2S (hydrogen sulfide), and NH.sub.3 (ammonia). The process may be an HVPE (hydride vapor phase epitaxy) process.

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.

A crystal substrate 1 includes an underlying layer 2 and a thick film 3. The underlying layer 2 is composed of a crystal of a nitride of a group 13 element and includes a first main face 2a and a second main face 2b. The thick film 3 is composed of a crystal of a nitride of a group 13 element and provided over the first main face of the underlying layer. The underlying layer 2 includes a low carrier concentration region 5 and a high carrier concentration region 4 both extending between the first main face 2a and the second main face 2b.

A vapor phase epitaxy method of growing a III-V layer with a doping that changes from a first conductivity type to a second conductivity type on a surface of a substrate or a preceding layer in a reaction chamber from the vapor phase from an epitaxial gas flow comprising a carrier gas, at least one first precursor for an element from main group III, and at least one second precursor for an element from main group V, wherein when a first growth height is reached, a first initial doping level of the first conductivity type is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor, then the first initial doping level is reduced to a second initial doping level of the first or low second conductivity type.

A method of manufacture and resulting structure for a single crystal electronic device with an enhanced strain interface region. The method of manufacture can include forming a nucleation layer overlying a substrate and forming a first and second single crystal layer overlying the nucleation layer. These first and second layers can be doped by introducing one or more impurity species to form the strained single crystal layers. The first and second strained layers can be aligned along the same crystallographic direction to form a strained single crystal bi-layer having an enhanced strain interface region. Using this enhanced single crystal bi-layer to form active or passive devices results in improved physical characteristics, such as enhanced photon velocity or improved density charges.

A buffer layer on a silicon carbide substrate and a method of forming the same are disclosed. The buffer layer includes at least two layers of silicon carbide films, in which at least each lower one is doped at a top surface thereof with predetermined ions. As a result, at the top surface of the silicon carbide film, a barrier with different parameter is formed, which can block dislocation defects that have spread into the silicon carbide film from further upward propagation in the silicon carbide film.

A method for manufacturing epitaxial films with multiple stress states, comprising steps of: providing a first single crystal substrate, and forming a sacrificial layer and a first epitaxial film on the first single crystal substrate, wherein the first epitaxial film is made of a first material;

removing the sacrificial layer to separate the first epitaxial film from the first single crystal substrate; transferring the first epitaxial film to a second single crystal substrate, wherein the second single crystal substrate is made of a second material, a partial surface of the second single crystal substrate being overlapped by the first epitaxial film; applying epitaxies onto the first epitaxial film and the second single crystal substrate to form a second epitaxial film on the first epitaxial film and the second single crystal substrate.

An epitaxial deposition process, such as atomic layer deposition, is provided for forming a thin film comprising beta-gallium oxide (β-Ga.sub.2O.sub.3) on a substrate, such as sapphire. The process involves depositing a buffer layer of metastable Ga.sub.2O.sub.3, such as α-Ga.sub.2O.sub.3, on the substrate, and then reacting a gallium precursor, such as TEG, with an oxygen precursor, such as oxygen plasma, to deposit a layer comprising β-Ga.sub.2O.sub.3 on the buffer layer. The Ga.sub.2O.sub.3 film formed by the process may comprise highly oriented crystalline β-Ga.sub.2O.sub.3, with negligible amounts of other Ga.sub.2O.sub.3 polymorphs.