Abstract: An apparatus and associated method for large-scale manufacturing of gallium nitride. The apparatus comprises a large diameter autoclave or internally-heated high pressure vessel, a seed rack, and a raw material basket. Methods include effective means for utilization of seed crystals. The apparatus and methods are scalable up to very large volumes and are cost effective.

Abstract: Alkaline-earth metals are used to reduce impurity incorporation into a Group-III nitride crystal grown using the ammonothermal method.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.

Abstract: An object is to reduce variation in shape of crystals that are to be formed. Solutions containing respective raw materials are made in an environment where an oxygen concentration is lower than that in air, the solutions containing the respective raw materials are mixed in an environment where an oxygen concentration is lower than that in air to form a mixture solution, and with use of the mixture solution, a composite oxide is formed by a hydrothermal method.

Abstract: A gallium nitride crystal with a polyhedron shape having exposed {10-10} m-planes and an exposed (000-1) N-polar c-plane, wherein a surface area of the exposed (000-1) N-polar c-plane is more than 10 mm2 and a total surface area of the exposed {10-10} m-planes is larger than half of the surface area of (000-1) N-polar c-plane. The GaN bulk crystals were grown by an ammonothermal method with a higher temperature and temperature difference than is used conventionally, using a high-pressure vessel with an upper region and a lower region. The temperature of the lower region is at or above 550° C., the temperature of the upper region is set at or above 500° C., and the temperature difference between the lower and upper regions is maintained at or above 30° C. GaN seed crystals having a longest dimension along the c-axis and exposed large area m-planes are used.

Abstract: Present invention discloses a high-pressure vessel of large size formed with a limited size of e.g. Ni—Cr based precipitation hardenable superalloy. Vessel may have multiple zones. For instance, the high-pressure vessel may be divided into at least three regions with flow-restricting devices and the crystallization region is set higher temperature than other regions. This structure helps to reliably seal both ends of the high-pressure vessel, at the same time, may help to greatly reduce unfavorable precipitation of group III nitride at the bottom of the vessel. Invention also discloses novel procedures to grow crystals with improved purity, transparency and structural quality. Alkali metal-containing mineralizers are charged with minimum exposure to oxygen and moisture until the high-pressure vessel is filled with ammonia. Several methods to reduce oxygen contamination during the process steps are presented.

Abstract: An apparatus and associated method for large-scale manufacturing of gallium nitride is provided. The apparatus comprises a large diameter autoclave and a raw material basket. Methods include metered addition of dopants in the raw material and control of the atmosphere during crystal growth. The apparatus and methods are scalable up to very large volumes and are cost effective.

Abstract: Provided is a base substrate with which a Group-III nitride crystal having a large area and a large thickness can be grown while inhibiting crack generation. A single-crystal substrate for use in growing a Group-III nitride crystal thereon, which satisfies the following expression (1), wherein Z1 (?m) is an amount of warpage of physical shape in a growth surface of the single-crystal substrate and Z2 (?m) is an amount of warpage calculated from a radius of curvature of crystallographic-plane shape in a growth surface of the single-crystal substrate: ?40<Z2/Z1<?1: Expression (1).

Abstract: To provide a production method for a nitride crystal, where a nitride crystal can be prevented from precipitating in a portion other than on a seed crystal and the production efficiency of a gallium nitride single crystal grown on the seed crystal can be enhanced. In a method for producing a nitride crystal by an ammonothermal method in a vessel containing a mineralizer-containing solution, out of the surfaces of said vessel and a member provided in said vessel, at least a part of the portion coming into contact with said solution is constituted by a metal or alloy containing one or more atoms selected from the group consisting of tantalum (Ta), tungsten (W) and titanium (Ti), and has a surface roughness (Ra) of less than 1.80 ?m.

Abstract: A method of hydrothermally synthesizing sapphire single crystals doped with trivalent metal ions in a crystal-growth autoclave including a crystal-growth zone and nutrient-dissolution zone in fluid communication with the crystal-growth zone is provided. Implementations of the method including situating within the crystal-growth zone at least one sapphire-based seed crystal and situating within the nutrient-dissolution zone an aluminum-containing material to serve as nutrient. An acidic, trivalent-metal-ion-containing growth solution is introduced into the cavity in a quantity sufficient, at least when heated to a predetermined average temperature, to immerse the at least one seed crystal and the nutrient in the growth solution. The growth solution is selected such that sapphire exhibits retrograde solubility therein and the growth process is carried out while maintaining an interior-cavity pressure within a range between and including each of 3.

Abstract: An ammonothermal growth of group-III nitride crystals on starting seed crystals with at least two surfaces making an acute, right or obtuse angle, i.e., greater than 0 degrees and less than 180 degrees, with respect to each other, such that the exposed surfaces together form a concave surface.

Abstract: A process for preparing various morphology NTE compound ZrW0.5Mo1.5O8 comprising: preparing 0.4M Zr4+ solution, 0.2M W6+ solution and 0.6M Mo6+ solution with zirconyl nitrate, ammonium tungstate and ammo-nium molybdate separately, mixing them with the same volume and stirring until they are mixed well, adding 6-12M hydrochloric acid with the volume of ?- 1/7 of the mixed solution, or adding 6-12M hydrochloric acid with the volume of ?-? of the mixed solution and 0.2-0.4 wt % ammonium monoacid phosphate of all raw materials, or adding 9-18M sulfuric acid with the volume of 1/10-? of the mixed solution, well mixing, transferring the mixed solution into the hydrothermal reactor, reacting at 150-180° C. for 8-25 hours, washing, drying and getting the precursor, heating the precursor at 480-500° C. for more than 5 hours and obtaining the product is provided.

Abstract: A high pressure apparatus and related methods for processing supercritical fluids. In a specific embodiment, the present apparatus includes a capsule, a heater, at least one ceramic ring but can be multiple rings, optionally, with one or more scribe marks and/or cracks present. In a specific embodiment, the apparatus optionally has a metal sleeve containing each ceramic ring. The apparatus also has a high-strength enclosure, end flanges with associated insulation, and a power control system. In a specific embodiment, the apparatus is capable of accessing pressures and temperatures of 0.2-2 GPa and 400-1200° C., respectively.

Abstract: A method for large-scale manufacturing of gallium nitride includes a process for reducing and/or minimizing contamination in the crystals, for solvent addition to an autoclave, for improving or optimizing the solvent atmosphere composition, for removal of the solvent from the autoclave, and for recycling of the solvent. The method is scalable up to large volumes and is cost effective.

Abstract: A method for ammonothermally growing group-III nitride crystals using an initially off-oriented non-polar and/or semi-polar growth surface on a group-III nitride seed crystal. Group-III-containing source materials and group-III nitride seed crystals are placed into a vessel, wherein the seed crystals have one or more non-polar or semi-polar growth surfaces. Group-III nitride crystals are ammonothermally grown by filling the vessel with a nitrogen-containing solvent for dissolving the source materials and transporting a fluid comprised of the solvent with the dissolved source materials to the seed crystals for growth of the group-III nitride crystals on the seed crystals. The growth surfaces are initially off-oriented growth surfaces, wherein the growth surfaces are off-oriented m-plane or highly vicinal m-plane growth surfaces. The growth surfaces of the seed crystals may be created by cutting group-III nitride crystals at a desired angle with respect to an m-plane.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.

Abstract: Described are nonlinear optical (NLO) crystals, including aluminum-borate NLO crystals, that have low concentrations of contaminants that adversely affect the NLO crystal's optical properties, such as compounds that contain transition-metal elements and/or lanthanides, other than yttrium, lanthanum, and lutetium. Some NLO crystals with low concentrations of these contaminants are capable of second harmonic generation at very short wavelengths. Also described are embodiments of a method for making these NLO crystals. Some embodiments involve growing a single NLO crystal, such as an aluminum-borate NLO crystal, from a mixture containing a solvent that is substantially free of harmful contaminants. The described NLO crystals can be used, for example, in laser devices.

Abstract: To grow a highly pure nitride crystal having a low oxygen concentration efficiently by an ammonothermal method. A process for producing a nitride crystal, which comprises bringing a reactant gas reactive with ammonia to form a mineralizer, and ammonia into contact with each other to prepare a mineralizer in a reactor or in a closed circuit connected to a reactor; and growing a nitride crystal by an ammonothermal method in the presence of the ammonia and the mineralizer.

Abstract: A method for large-scale manufacturing of gallium nitride includes a process for reducing and/or minimizing contamination in the crystals, for solvent addition to an autoclave, for improving or optimizing the solvent atmosphere composition, for removal of the solvent from the autoclave, and for recycling of the solvent. The method is scalable up to large volumes and is cost effective.

Abstract: A zinc oxide based substrate satisfies a condition that impurities Si, C, Ge, Sn, and Pb which are Group IV elements each have a concentration of 1×1017 cm?3 or less. More preferably, the zinc oxide based substrate 2 satisfies a condition that impurities Li, Na, K, Rb, and Fr which are Group I elements each have a concentration of 1×1016 cm?3 or less. The impurity concentration of a zinc oxide based semiconductor grown on the zinc oxide based substrate can be reduced in this manner.

Abstract: A crystal growth method of a group III nitride includes the steps of forming a melt mixture of an alkali metal and a group III element in a reaction vessel, and growing a crystal of a group III nitride formed of the group III element and nitrogen from the melt mixture in the reaction vessel, wherein the step of growing the crystal of the group III nitride is conducted while controlling an increase rate of degree of supersaturation of a group III nitride component in the melt mixture in a surface region of the melt mixture.

Abstract: Millimeter-scale GaN single crystals in filamentary form, also known as GaN whiskers, grown from solution and a process for preparing the same at moderate temperatures and near atmospheric pressures are provided. GaN whiskers can be grown from a GaN source in a reaction vessel subjected to a temperature gradient at nitrogen pressure. The GaN source can be formed in situ as part of an exchange reaction or can be preexisting GaN material. The GaN source is dissolved in a solvent and precipitates out of the solution as millimeter-scale single crystal filaments as a result of the applied temperature gradient.

Abstract: To produce a zinc oxide single crystal having a sufficiently low lithium concentration and a high crystallinity. A zinc oxide crystal is grown by hydrothermal synthesis method using a solution having a lithium concentration of 1 ppm or less (weight basis), while suppressing a fluctuation range of crystal growth temperature within 5° C. or at a temperature within the range of 300 to 370° C.

Abstract: A high quality single-crystalline polyalkylthiophene structure can be easily prepared by the inventive method which comprises: (i) dissolving polyalkylthiophene in an organic solvent at a temperature ranging from 50 to 100° C., sequentially quenching the polyalkylthiophene solution at a temperature ranging from 25 to 40° C. and then at ?5 to 15° C., to obtain a self-seeding polyalkylthiophene solution; and (ii) applying the self-seeding polyalkylthiophene solution obtained in step (i) to one surface of a nano-template having a hydrophobic supramolecule coating layer formed thereon to induce self-assembly and crystallization of polyalkylthiophene on the surface.

Abstract: A semiconductor nanocrystal composition comprising a Group V to VI semiconductor material and a method of making same. The method includes synthesizing a semiconductor nanocrystal core, where the synthesizing includes dissolving a Group V to VI anion gas in a first solvent to produce a Group V to VI anion precursor, preparing a cation precursor, and reacting the Group V to VI anion precursor with the cation precursor in the presence of a second solvent. The reacting may occur in a high pressure vessel.

Abstract: In a method of growing a single crystal by melting a raw material within a vessel under a nitrogenous and non-oxidizing atmosphere, the vessel is oscillated and the melted raw material is contacted with an agitation medium made of a solid unreactive with the melted raw material.

Abstract: A nitride single crystal is produced using a growth solution containing an easily oxidizable material. A crucible for storing the growth solution, a pressure vessel for storing the crucible and charging an atmosphere containing at least nitrogen, and an oxygen absorber disposed inside the pressure vessel and outside the crucible are used to grow the nitride single crystal.

Abstract: Single, acentric, rhombohedral, fluoroberyllium borate crystals of a size sufficient for use in a variety of laser and non-optical applications are formed by a hydrothermal method.

Abstract: In a synthetic method for porous silica crystals through a hydrothermal reaction, a method for synthesizing porous silica crystals with a size of 0.5 mm or larger in high reproducibility and efficiency is provided using a method for manufacturing the porous silica crystals, wherein a high concentration area with silicon is formed as a partial area inside a hydrothermal synthesis vessel, and at least a part of a surface-smoothed bulk material is present in the high concentration area with silicon to perform the hydrothermal reaction, the bulk material comprising a compound containing both silicon and oxygen as a supply source for a part or a whole of the structure composition elements of the porous silica crystals.

Abstract: The present invention belongs to a method for preparing organic ligand-capped titanium dioxide nanocrystals, wherein the method comprises steps of using methyl titanate, ethyl titanate, n-propyl titanate, iso-propyl titanate, butyl titanate or titanium tetrachloride as a titanium source, and with capping by oleic acid or an organic capping agent, reacting the titanium source in an organic non-polar solvent with an aqueous alkaline substance solution in the interface at a temperature of 25 to 280° C. for 0.5 to 240 hrs, thus a transparent sol containing titanium dioxide nanocrystals is obtained, said the titanium dioxide nanocrystals have particle diameters of 1-20 nm. The preparing process has the features of mild reaction conditions and is a simpler and easier method with a shorter preparation period, thereby facilitating the industrialization.

Abstract: The present disclosure proves for new design of reactors used for ammonothermal growth of III nitride crystals. The reactors include a region intermediate a source dissolution region and a crystal growth region configured to provide growth of high quality crystals at rates greater than 100 ?m/day. In one embodiment, multiple baffle plates having openings whose location is designed so that there is no direct path through the intermediate region, or with multiple baffle plates having differently sized openings on each plate so that the flow is slowed down and/or exhibit greater mixing are described. The disclosed designs enables obtaining high temperature difference between the dissolution region and the crystallization region without decreasing conductance through the device.

Abstract: An artificial corundum crystal which can be put into practical use at low costs, and a process for producing the same. The artificial corundum crystal contains a seed crystal and has at least one crystal face selected from a {113} face, a {012} face, a {104} face, a {110} face, a {101} face, a {116} face, a {211} face, a {122} face, a {214} face, a {100} face, a {125} face, a {223} face, a {131} face, and a {312} face. The process for producing the artificial corundum crystal an artificial corundum crystal having a hexagonally dipyramidal includes forming with a seed crystal by a flux evaporation method of heating a sample containing a raw material and a flux to precipitate a crystal and grow the crystal by use of flux evaporation as a driving force.

Abstract: A method for large-scale manufacturing of gallium nitride includes a process for reducing and/or minimizing contamination in the crystals, for solvent addition to an autoclave, for improving or optimizing the solvent atmosphere composition, for removal of the solvent from the autoclave, and for recycling of the solvent. The method is scalable up to large volumes and is cost effective.

Abstract: A method for large-scale manufacturing of gallium nitride boules. Large-area single crystal seed plates are suspended in a rack, placed in a large diameter autoclave or internally-heated high pressure apparatus along with ammonia and a mineralizer, and grown ammonothermally. The seed orientation and mounting geometry are chosen to provide efficient utilization of the seed plates and of the volume inside the autoclave or high pressure apparatus. The method is scalable up to very large volumes and is cost effective.

Abstract: A high pressure apparatus and related methods for processing supercritical fluids. In a specific embodiment, the present apparatus includes a capsule, a heater, at least one ceramic ring but can be multiple rings, optionally, with one or more scribe marks and/or cracks present. In a specific embodiment, the apparatus optionally has a metal sleeve containing each ceramic ring. The apparatus also has a high-strength enclosure, end flanges with associated insulation, and a power control system. IN a specific embodiment, the apparatus is capable of accessing pressures and temperatures of 0.2-2 GPa and 400-1200° C., respectively.

Abstract: An improved capsule for processing materials or growing crystals in supercritical fluids. The capsule 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 is capable of processing materials at pressures and temperatures of 0.2-8 GPa and 400-1500° C., respectively. Of course, there can be other variations, modifications, and alternatives.

Abstract: The invention provides a method for the production of a photonic device comprising providing a substrate, forming in the substrate substantially straight pores, lining or filling the pores with a material having voltage-dependent index of refraction, and removing part but not all of the substrate materials so that an array remains of tubes or rods of material having voltage-dependent index of refraction. In a variant of the method the deposited material is piezoelectric and the substrate is completely removed, resulting in piezoelectric tubes or rods of small diameter, generally below 10 ?m.

Abstract: A corundum crystal formed body having a corundum crystal grown directly on a base material and a production process capable of producing the corundum crystal formed body easily at low costs. The a corundum crystal formed body has a platinum base material and a corundum crystal portion formed on the platinum base material. Further, the process for producing a corundum crystal formed body involves forming a corundum crystal on a platinum base material by a flux evaporation method of heating a sample containing a raw material and a flux to precipitate a crystal. The crystal is grown by use of flux evaporation as a driving force.

Abstract: Scandium, yttrium, and lanthanide sesquioxide crystals having the formula Ln2O3, wherein Ln is selected from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, with or without an activator ion, are made by a hydrothermal method for a variety of end-use applications

Abstract: A system and method for growing diamond crystals from diamond crystal seeds by epitaxial deposition at low temperatures and atmospheric and comparatively low pressures. A solvent is circulated (by thermal convection and/or pumping), wherein carbon is added in a hot leg, transfers to a cold leg having, in some embodiments, a range of progressively lowered temperatures and concentrations of carbon via the circulating solvent, and deposits layer-by-layer on diamond seeds located at the progressively lower temperatures since as diamond deposits the carbon concentration lowers and the temperature is lowered to keep the solvent supersaturated. The solvent includes metal(s) or compound(s) that have low melting temperatures and transfer carbon at comparatively low temperatures. A controller receives parameter signals from a variety of sensors located in the system, processes these signals, and optimizes diamond deposition by outputting the necessary control signals to a plurality of control devices (e.g.

Abstract: Single, acentric, rhombohedral, potassium fluoroberyllium borate crystals of a size sufficient for use in a variety of laser and non-optical applications are formed by a hydrothermal method.

Abstract: The invention relates to the field of CdTe or CdZnTe single crystal production and to an improved solid-phase method of obtaining large CdTe or CdZnTe crystals having an excellent crystalline structure.

Abstract: A growth apparatus is used having a plurality of crucibles 10 each for containing the solution, a heating element for heating the crucible, and a pressure vessel for containing at least the crucibles and the heating element and for filling an atmosphere comprising at least nitrogen gas. One seed crystal is put in each of the crucibles to grow the nitride single crystal on the seed crystal.

Abstract: A method for producing a Group III element nitride single crystal, which comprises reacting at least one Group III element selected from the group consisting of gallium(Ga), aluminum(Al) and indium(In) with nitrogen(N) in a mixed flux of sodium(Na) and at least one of an alkali metal (except Na) and an alkaline earth metal. The method allows the production, with a good yield, of the single crystal of a group III element nitride which is transparent, is reduced in the density of dislocation, has a bulk form, and is large. In particular, a gallium nitride single crystal produced by the method has high quality and takes a large and transparent bulk form, and thus has a high practical value.

Abstract: The template type substrate is used for opto-electric or electrical devices and comprises A) a layer of bulk mono-crystal nitride containing at least one element of alkali metals (Group I, IUPAC 1989) and B) a layer of nitride grown by means of vapor phase epitaxy growth wherein the layer A) and the layer B) are combined at non N-polar face of the layer A) and N-polar face of the layer B). Therefore, the template type substrate has a good dislocation density and a good value of FWHM of the X-ray rocking curve from (0002) plane less than 80, so that the resulting template type substrate is very useful for the epitaxy substrate from gaseous phase such as MOCVD, MBE and HVPE, resulting in possibility of making good opto-electric devices such as Laser Diode and large-output LED and good electric devices such as MOSFET.

Abstract: Acentric, tetragonal lithium borate crystals are disclosed along with a hydrothermal method for forming such crystals. The crystals possess unique optical, non-linear optical, and other photonic properties and may be formed of sufficient size to be useful in a wide variety of photonic devices. In addition, the disclosed crystals are very hard and can be used in specialty grinding applications such as for grinding optical components for deep UV applications.

Abstract: A method of growing group III-nitride crystals in a mixture of supercritical ammonia and nitrogen, and the group-III crystals grown by this method. The group III-nitride crystal is grown in a reaction vessel in supercritical ammonia using a source material or nutrient that is polycrystalline group III-nitride, amorphous group III-nitride, group-III metal or a mixture of the above, and a seed crystal that is a group-III nitride single crystal. In order to grow high-quality group III-nitride crystals, the crystallization temperature is set at 550° C. or higher. Theoretical calculations show that dissociation of NH3 at this temperature is significant. However, the dissociation of NH3 is avoided by adding extra N2 pressure after filling the reaction vessel with NH3.

Abstract: A method for a growing solid-state, spectrometer grade II-VI crystal using a high-pressure hydrothermal process including the following steps: positioning seed crystals in a growth zone of a reactor chamber; positioning crystal nutrient material in the nutrient zone of the chamber; filling the reactor with a solvent fluid; heating and pressuring the chamber until at least a portion of the nutrient material dissolves in the solvent and the solvent becomes supercritical in the nutrient zone; transporting supercritical from the nutrient zone to the growth zone, and growing the seed crystals as nutrients from the supercritical fluid deposit on the crystals.

Abstract: The invention is directed to a method for growing metal fluoride crystals suitable for use in below 200 nm optical lithography systems, the method comprising including at least the step of heating a crystal growth furnace to a temperature in the range of 1400-2000° C. to purify the furnace by removal of sulfur and chlorine prior to using the furnace for growing metal fluoride single crystals.

Abstract: A method for growing gallium nitride (GaN) crystals in supercritical ammonia using an autoclave is disclosed. Large surface area GaN crystals are created, which may include calcium, magnesium or vanadium or less than 1% indium.