A method of processing a gallium nitride substrate, includes providing a gallium nitride substrate, polishing a surface of the gallium nitride substrate, and cleaning the polished surface of the gallium nitride substrate. The polished surface includes a GaL/CK peak intensity ratio in energy dispersive X-ray microanalysis (EDX) spectrum which is not less than 2, the EDX spectrum being obtained in an EDX of the surface of the gallium nitride substrate using a scanning electron microscope (SEM) at an accelerating voltage of 3 kV.

Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.

Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.

A chemical vapor deposition (CVD) reactor includes a resonating cavity configured to receive microwaves. A microwave transparent window positioned in the resonating cavity separates the resonating cavity into an upper zone and a plasma zone. Microwaves entering the upper zone propagate through the microwave transparent window into the plasma zone. A substrate is disposed proximate a bottom of the plasma zone opposite the microwave transparent window. A ring structure, positioned around a perimeter of the substrate in the plasma zone, includes a lower section that extends from the bottom of the resonating cavity toward the microwave transparent window and an upper section on a side of the lower section opposite the bottom of the resonating cavity. The upper section extends radially toward a central axis of the ring structure. An as-grown diamond film on the substrate is also disclosed.

The present application is directed to a filter and methods of making the same. The filter includes a block of dielectric material with a top surface including a patterned region, a bottom surface, and side surfaces. The filter also includes a through-hole extending through the block from the top surface to the bottom surface. The through-hole is partially surrounded by the patterned region, The filter also includes a wall extending from the top surface, the wall having an inner surface, an outer surface, and a roof. The bottom surface, side surfaces, outer surface, and roof have a first coating including glass frit. The patterned region, through-hole and inner surface have a second coating including glass frit. The glass frit in the first coating is at least 0.5% greater than the glass frit in the second coating. The application is also directed to a system including a printed circuit board and a filter.

Methods for producing nanostructures from copper-based catalysts on porous substrates, particularly silicon nanowires on carbon-based substrates for use as battery active materials, are provided. Related compositions are also described. In addition, novel methods for production of copper-based catalyst particles are provided. Methods for producing nanostructures from catalyst particles that comprise a gold shell and a core that does not include gold are also provided.

This invention is related to a method for the preparation of halide perovskite or perovskite-related materials on a substrate and to optoelectronic devices and photovoltaic cells comprising the perovskites prepared by the methods of this invention The method for the preparation of the perovskite includes a direct conversion of elemental metal or metal alloy to halide perovskite or perovskite-related materials.

The disclosure relates to a method for making semimetal compound of Pt. The semimetal compound is a single crystal material of PtSe.sub.2. The method comprises: placing pure Pt and pure Se in a reacting chamber as reacting materials; evacuating the reacting chamber to be vacuum less than 10 Pa; heating the reacting chamber to a first temperature of 600 degrees Celsius to 800 degrees Celsius and keeping for 24 hours to 100 hours; cooling the reacting chamber to a second temperature of 400 degrees Celsius to 500 degrees Celsius at a cooling rate of 1 degrees Celsius per hour to 10 degrees Celsius per hour and keeping for 24 hours to 100 hours to obtain a crystal material of PtSe.sub.2; and separating the excessive reacting materials from the crystal material of PtSe.sub.2.

The disclosure relates to a method for making semimetal compound of Pt. The semimetal compound is a single crystal material of PtSe.sub.2. The method comprises: placing pure Pt and pure Se in a reacting chamber as reacting materials; evacuating the reacting chamber to be vacuum less than 10 Pa; heating the reacting chamber to a first temperature of 600 degrees Celsius to 800 degrees Celsius and keeping for 24 hours to 100 hours; cooling the reacting chamber to a second temperature of 400 degrees Celsius to 500 degrees Celsius at a cooling rate of 1 degrees Celsius per hour to 10 degrees Celsius per hour and keeping for 24 hours to 100 hours to obtain a crystal material of PtSe.sub.2; and separating the excessive reacting materials from the crystal material of PtSe.sub.2.

Implementations of the present disclosure generally relate to the fabrication of integrated circuits. More specifically, implementations disclosed herein relate to apparatus, systems, and methods for reducing substrate outgassing. A substrate is processed in an epitaxial deposition chamber for depositing an arsenic-containing material on a substrate and then transferred to a degassing chamber for reducing arsenic outgassing on the substrate. The degassing chamber includes a gas panel for supplying hydrogen, nitrogen, and oxygen and hydrogen chloride or chlorine gas to the chamber, a substrate support, a pump, and at least one heating mechanism. Residual or fugitive arsenic is removed from the substrate such that the substrate may be removed from the degassing chamber without dispersing arsenic into the ambient environment.