A method of processing a silicon surface includes using a first radical species to remove contamination from the surface and to roughen the surface; and using a second radical species to smooth the roughened surface. Reaction systems for performing such a method, and silicon surfaces prepared using such a method, also are provided.

Provided are a substrate for epitaxially growing a diamond crystal, having at least a surface made of a metal, in which the above surface made of the metal is a plane having an off angle of more than 0, and the full width at half maximum of the X-ray diffraction peak from the (002) plane by the X-ray rocking curve measurement at the above surface made of the metal is 300 seconds or less; and a method of manufacturing a diamond crystal, including epitaxially growing a diamond crystal on the above surface made of the metal of the above substrate.

A multilayer structure of the present invention is a multilayer structure including a base substrate and a semiconductor film that is made of -Ga.sub.2O.sub.3 or an -Ga.sub.2O.sub.3-based solid solution and has a corundum crystal structure, the semiconductor film being disposed on the base substrate. The semiconductor film has an average film thickness of greater than or equal to 10 m. The semiconductor film is convexly or concavely warped. An amount of warpage of the semiconductor film is 20 m or greater and 64 m or less.

A preparation method of an aluminum nitride (AlN) composite structure based on a two-dimensional (2D) crystal transition layer is provided. The preparation method includes: transferring the 2D crystal transition layer on a first periodic groove of an epitaxial substrate; forming a second periodic groove staggered with the first periodic groove on the 2D crystal transition layer; depositing a supporting protective layer; depositing a functional layer of a required AlN-based material; and removing the 2D crystal transition layer through thermal oxidation to obtain a semi-suspended AlN composite structure. The preparation method has low difficulty and is suitable for large-scale industrial production. Design windows of the periodic grooves and the AlN functional layer are large and can meet the material requirements of deep ultraviolet light-emitting diodes (DUV-LEDs) and radio frequency (RF) electronic devices for different purposes, resulting in a wide application range.

Exemplary semiconductor structures may include a silicon-containing substrate. The structures may include a layer of a metal nitride overlying the silicon-containing substrate. The structures may include a gallium nitride structure overlying the layer of the metal nitride. The structures may include an oxygen-containing layer disposed between the layer of the metal nitride and the gallium nitride structure.

Methods of depositing transition metal dichalcogenide (TMDC) films are described. The TMDC films can be used in electronic devices as, for example, a channel material in both back-end-of-line (BEOL) and front-end-of line (FEOL) applications depending on the TMDC growth temperature.

A silicon carbide epitaxial substrate according to the present disclosure includes: a silicon carbide substrate; a first silicon carbide epitaxial layer disposed on the silicon carbide substrate; and a second silicon carbide epitaxial layer disposed on the first silicon carbide epitaxial layer. When an area density of first particles in the first silicon carbide epitaxial layer is defined as a first area density and an area density of second particles in the second silicon carbide epitaxial layer is defined as a second area density, a value determined by dividing the first area density by the second area density is more than 0.5 and less than 1. The first particles and the second particles each have a maximum diameter of 2 m to 50 m.

A method of forming conductive member includes: forming, on substrate, first portion containing first element constituting the conductive member to be obtained and second element causing eutectic reaction with the first element, and second portion containing third element constituting intermetallic compound with the second element; crystallizing primary crystals of the first element by adjusting temperature of the substrate after bringing the first portion into liquid phase state; growing crystal grains of the first element by diffusing the second element from the first portion into the second portion to increase ratio of the first element in crystal state to the first and second elements in the liquid phase state in the first portion while maintaining the temperature of the substrate at the same temperature; and turning the first portion, after completing diffusion of the second element into the second portion, into the conductive member having crystal grains of the first element.

A method of processing a silicon surface includes using a first radical species to remove contamination from the surface and to roughen the surface; and using a second radical species to smooth the roughened surface. Reaction systems for performing such a method, and silicon surfaces prepared using such a method, also are provided.