Abstract: A method for growing a crystalline composition, the first crystalline composition may include gallium and nitrogen. The crystalline composition may have an infrared absorption peak at about 3175 cm?1, with an absorbance per unit thickness of greater than about 0.01 cm?1. In one embodiment, the composition ay have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the first crystalline composition.

Abstract: A method for growing a crystalline composition, the first crystalline composition may include gallium and nitrogen. The crystalline composition may have an infrared absorption peak at about 3175 cm?1, with an absorbance per unit thickness of greater than about 0.01 cm?1. In one embodiment, the composition ay have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the first crystalline composition.

Abstract: A pressure release mechanism for use with a capsule for processing materials or growing crystals in supercritical fluids is disclosed. The capsule with the pressure release mechanism is scalable up to very large volumes and is cost effective according to a preferred embodiment. In conjunction with suitable high pressure apparatus, the capsule with pressure release mechanism is capable of processing materials at pressures and temperatures of 20-2000 MPa and 25-1500° C., respectively. Of course, there can be other variations, modifications, and alternatives.

Abstract: A method for growing a crystalline composition, the first crystalline composition may include gallium and nitrogen. The crystalline composition may have an infrared absorption peak at about 3175 cm?1, with an absorbance per unit thickness of greater than about 0.01 cm?1. In one embodiment, the composition may have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the first crystalline composition.

Abstract: A pressure release mechanism for use with a capsule for processing materials or growing crystals in supercritical fluids is disclosed. The capsule with the pressure release mechanism is scalable up to very large volumes and is cost effective according to a preferred embodiment. In conjunction with suitable high pressure apparatus, the capsule with pressure release mechanism is capable of processing materials at pressures and temperatures of 20-2000 MPa and 25-1500° C., respectively. Of course, there can be other variations, modifications, and alternatives.

Abstract: A method for growing a crystalline composition, the first crystalline composition may include gallium and nitrogen. The crystalline composition may have an infrared absorption peak at about 3175 cm?1, with an absorbance per unit thickness of greater than about 0.01 cm?1. In one embodiment, the composition may have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the first crystalline composition.

Abstract: A method for growing a crystalline composition, the first crystalline composition may include gallium and nitrogen. The crystalline composition may have an infrared absorption peak at about 3175 cm?1, with an absorbance per unit thickness of greater than about 0.01 cm?1. In one embodiment, the composition may have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the first crystalline composition.

Abstract: There is provided a GaN single crystal at least about 2.75 millimeters in diameter, with a dislocation density less than about 104 cm?1, and having substantially no tilt boundaries. A method of forming a GaN single crystal is also disclosed. The method includes providing a nucleation center, a GaN source material, and a GaN solvent in a chamber. The chamber is pressurized. First and second temperature distributions are generated in the chamber such that the solvent is supersaturated in the nucleation region of the chamber. The first and second temperature distributions have different temperature gradients within the chamber.

Abstract: A method for removing defects at high pressure and high temperature (HP/HT) or for relieving strain in a non-diamond crystal commences by providing a crystal, which contains defects, and a pressure medium. The crystal and the pressure medium are disposed in a high pressure cell and placed in a high pressure apparatus, for processing under reaction conditions of sufficiently high pressure and high temperature for a time adequate for one or more of removing defects or relieving strain in the single crystal.

Abstract: A method for growing a crystalline composition, the first crystalline composition may include gallium and nitrogen. The crystalline composition may have an infrared absorption peak at about 3175 cm?1, with an absorbance per unit thickness of greater than about 0.01 cm?1. In one embodiment, the composition ay have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the first crystalline composition.

Abstract: A composition including a polycrystalline metal nitride having a number of grains is provided. These grains have a columnar structure with one or more properties such as, an average grain size, a tilt angle, an impurity content, a porosity, a density, and an atomic fraction of the metal in the metal nitride.

Abstract: A composition including a polycrystalline metal nitride having a number of grains is provided. These grains have a columnar structure with one or more properties such as, an average grain size, a tilt angle, an impurity content, a porosity, a density, and an atomic fraction of the metal in the metal nitride. An apparatus for preparing a metal nitride is provided. The apparatus may include a housing having an interior surface that defines a chamber and an energy source to supply energy to the chamber. A first inlet may be provided to flow a nitrogen-containing gas into the chamber. Raw materials may be introduced into the chamber through a raw material inlet. A second inlet may be provided to flow in a halide-containing gas in the chamber. The apparatus may further include a controller, which communicates with the various components of the apparatus such as, sensors, valves, and energy source, and may optimize and control the reaction.

Abstract: A method of making a metal nitride is provided. The method may include introducing a metal in a chamber. A nitrogen-containing material may be flowed into the chamber. Further, a hydrogen halide may be introduced. The nitrogen-containing material may react with the metal in the chamber to form the metal nitride.

Abstract: A crystalline composition is provided that includes gallium and nitrogen. The crystalline composition may have an amount of oxygen present in a concentration of less than about 3×1018 per cubic centimeter, and may be free of two-dimensional planar boundary defects in a determined volume of the crystalline composition. The volume may have at least one dimension that is about 2.75 millimeters or greater, and the volume may have a one-dimensional linear defect dislocation density of less than about 10,000 per square centimeter.

Abstract: A crystal comprising gallium nitride is disclosed. The crystal has at least one grain having at least one dimension greater than 2.75 mm, a dislocation density less than about 104 cm?2, and is substantially free of tilt boundaries.

Abstract: There are provided simplified methods for etching diamond, as compared to conventional methods. More particularly, the methods disclosed herein involve contacting at least a portion of the diamond with a metal or metal oxide so that redox etching of the contacted portion of the diamond occurs. Also provided are diamonds polished using the present method, as well as optical windows, heat sinks, cutting tools and electrical components incorporating diamonds polished/etched via the disclosed method.

Abstract: An apparatus and methods for forming a diamond film, are provided. An example of an apparatus for forming a diamond film includes an electrodeless microwave plasma reactor having a microwave plasma chamber configured to contain a substrate and to contain a reactant gas excited by microwaves to generate a microwave plasma discharge. Gas injection ports extend through an outer wall of the plasma chamber at a location upstream of the plasma discharge and above the substrate. Gas jet injection nozzles interface with the gas injection ports and are configured to form a directed gas stream of reactant gas having sufficient kinetic energy to disturb a boundary layer above an operational surface of the substrate to establish a convective transfer of the film material to the operational surface of the substrate.

Abstract: A heater that may include an outer housing and an inner tube is provided. The inner tube is in a coaxial relation to and within the outer housing. An inward facing surface of the inner tube defines a volume sufficient to receive a reaction capsule, and the outward facing surface is radially spaced from an inward facing surface of the outer housing sufficient to define a gap. A filler material is disposed within the gap. The filler material responds to pressure such that the filler volume is reduced by less than 5 volume percent at greater than 500 MPa pressure and at greater than 500° C. temperature. One or more heating elements are disposed in the gap. The heating elements are in thermal communication with the inner tube.

Abstract: An apparatus and method for processing materials in supercritical fluids is disclosed. The apparatus includes a capsule configured to contain a supercritical fluid, a high strength enclosure disposed about the capsule and a sensor configured to sense pressure difference between an interior and an exterior of the capsule. The apparatus also includes a pressure control device configured to adjust pressure difference of the capsule in response to the pressure difference sensed by the sensor. The apparatus further includes at least one dividing structure disposed within the capsule that divides the capsule into a seed growing chamber and a nutrient chamber.

Abstract: A method for growing a nitride crystal and a crystalline composition selected from one of AlN, InGaN, AlGaInN, InGaN, and AlGaNInN is provided. The composition comprises a true single crystal, grown from a single nucleus, at least 1 mm in diameter, free of lateral strain and tilt boundaries, with a dislocation density less than about 104 cm?2.