Abstract: An optical wavelength conversion element includes a cesium-lithium-borate crystal processed into a 10-mm long optical element cut in an orientation that allows a fourth harmonic of a Nd:YAG laser to be generated. A transmittance (Ta) at 3589 cm?1 in an infrared transmission spectrum of the optical element is used as an index that indicates a content of water impurities in the crystal and is independent of a polarization direction. An actual measurement of the transmittance Ta is at least 1%, without taking into account loss at an optically polished surface of the crystal. A wavelength conversion device, a ultraviolet laser irradiation apparatus, a laser processing system, and a method of manufacturing an optical wavelength conversion element are also described.

Abstract: A method of manufacturing group III-nitride semiconductor crystal includes the steps of accommodating an alloy containing at least a group III-metal element and an alkali metal element in a reactor, introducing a nitrogen-containing substance in the reactor, dissolving the nitrogen-containing substance in an alloy melt in which the alloy has been melted, and growing group III-nitride semiconductor crystal is provided. The group III-nitride semiconductor crystal attaining a small absorption coefficient and an efficient method of manufacturing the same, as well as a group III-nitride semiconductor device attaining high light emission intensity can thus be provided.

Abstract: A method for analyzing a sample in a liquid is provided, which is suitable for easily and reliably preventing a liquid for analysis from being evaporated. When the sample in the liquid is observed by using a scanning probe microscope (SPM), a sealing liquid (17) immiscible with a liquid for analysis (16) is filled around the liquid for analysis (16), in which a sample (13) and a probe (15) are immersed, so as to form a sealing state, in which the liquid for analysis (16) is isolated from an external gas. The SPM enables the probe (15) disposed on a front end of a cantilever (14) to approach a surface of the sample (13) immersed in the liquid, scans the surface of the sample, and detects an interaction between the sample (13) and the probe (15), thereby generating an image.

Abstract: A method for producing a high-quality group-III element nitride crystal at a high crystal growth rate, and a group-III element nitride crystal are provided. The method includes the steps of placing a group-III element, an alkali metal, and a seed crystal of group-III element nitride in a crystal growth vessel, pressurizing and heating the crystal growth vessel in an atmosphere of nitrogen-containing gas, and causing the group-III element and nitrogen to react with each other in a melt of the group-III element, the alkali metal and the nitrogen so that a group-III element nitride crystal is grown using the seed crystal as a nucleus. A hydrocarbon having a boiling point higher than the melting point of the alkali metal is added before the pressurization and heating of the crystal growth vessel.

Abstract: The present invention provides a method for producing a semiconductor substrate, the method including reacting nitrogen (N) with gallium (Ga), aluminum (Al), or indium (In), which are group III elements, in a flux mixture containing a plurality of metal elements selected from among alkali metals and alkaline earth metals, to thereby grow a group III nitride based compound semiconductor crystal. The group III nitride based compound semiconductor crystal is grown while the flux mixture and the group III element are mixed under stirring. At least a portion of a base substrate on which the group III nitride based compound semiconductor crystal is grown is formed of a flux-soluble material, and the flux-soluble material is dissolved in the flux mixture, at a temperature near the growth temperature of the group III nitride based compound semiconductor crystal, during the course of growth of the semiconductor crystal.

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: A method of growing hexagonal boron nitride single crystal is provided. Hexagonal boron nitride single crystal is grown in calcium nitride flux by heating, or heating and then slowly cooling, boron nitride and a calcium series material in an atmosphere containing nitrogen. Bulk hexagonal boron nitride single crystal can thereby successfully be grown.

Abstract: A method for producing Group-III-element nitride crystals by which an improved growth rate is obtained and large high-quality crystals can be grown in a short time, a producing apparatus used therein, and a semiconductor element obtained using the method and the apparatus are provided. The method is a method for producing Group-III-element nitride crystals that includes a crystal growth process of subjecting a material solution containing a Group III element, nitrogen, and at least one of alkali metal and alkaline-earth metal to pressurizing and heating under an atmosphere of a nitrogen-containing gas so that the nitrogen and the Group III element in the material solution react with each other to grow crystals.

Abstract: A method for manufacturing Group III nitride crystals with high quality is provided. By the method, a crystal raw material solution and gas containing nitrogen are introduced into a reactor vessel, which is heated, and crystals are grown in an atmosphere of pressure applied thereto. The gas is introduced from a gas supplying device to the reactor vessel through a gas inlet of the reactor vessel, and then is exhausted to the inside of a pressure-resistant vessel through a gas outlet of the reactor vessel. Since the gas is introduced directly to the reactor vessel, impurities attached to the pressure-resistant vessel and the like into the crystal growing site can be prevented. Further, the gas flows through the reactor vessel, to suppress aggregation of an evaporating alkali metal, etc., at the gas inlet and reduce flow of the metal vapor into the gas supplying device.

Abstract: A borate-based crystal excellent in uniformity and reliability, which is useful as an optical wavelength conversion device, etc., and can be easily produced at low cost in a short period of time, by the steps of dissolving water-soluble starting materials in water to prepare an aqueous solution, evaporating water in the aqueous solution followed by sintering or evaporating the water and not sintering, thereby forming a crystal growth material, and melting the resultant material to grow a crystal. Further, a highly reliable laser oscillation apparatus can be achieved by using this crystal as an optical wavelength conversion device.

Abstract: An object of the invention is to carry out the flux method with improved work efficiency while maintaining the purity of flux at high level and saving flux material cost. The sodium-purifying apparatus includes a sodium-holding-and-management apparatus for maintaining purified sodium (Na) in a liquid state. Liquid sodium is supplied into a sodium-holding-and-management apparatus through a liquid-sodium supply piping maintained at 100° C. to 200° C. The sodium-holding-and-management apparatus further has an argon-gas-purifying apparatus for controlling the condition of argon (Ar) gas that fills the internal space thereof. Thus, by opening and closing a faucet at desired timing, purified liquid sodium (Na) supplied from the sodium-purifying apparatus can be introduced into a crucible as appropriate via the liquid-sodium supply piping, the sodium-holding-and-management apparatus, and the piping.

Abstract: A light-emitting apparatus composed of a light source that emits primary light and a phosphor that absorbs the primary light and emits secondary light offers high brightness, low power consumption, and a long lifetime while minimizing adverse effects on the environment. The phosphor is formed of a III-V group semiconductor in the form of fine-particle crystals each having a volume of 2 800 nm3 or less. The light emitted from the fine-particle crystals depends on their volume, and therefore giving the fine-particle crystals a predetermined volume distribution makes it possible to adjust the wavelength range of the secondary light.

Abstract: A GaN single crystal 20 is grown on a crystal growth surface of a seed crystal (GaN layer 13) through the flux method in a nitrogen (N2) atmosphere at 3.7 MPa and 870° C. employing a flux mixture including Ga, Na, and Li at about 870° C. Since the back surface of the template 10 is R-plane of the sapphire substrate 11, the template 10 is readily corroded or dissolved in the flux mixture from the back surface thereof. Therefore, the template 10 is gradually dissolved or corroded from the back surface thereof, resulting in separation from the semiconductor or dissolution in the flux. When the GaN single crystal 20 is grown to a sufficient thickness, for example, about 500 ?m or more, the temperature of the crucible is maintained at 850° C. to 880° C., whereby the entirety of the sapphire substrate 11 is dissolved in the flux mixture.

Abstract: A method for producing a high-quality group-III element nitride crystal at a high crystal growth rate, and a group-III element nitride crystal are provided. The method includes the steps of placing a group-III element, an alkali metal, and a seed crystal of group-III element nitride in a crystal growth vessel, pressurizing and heating the crystal growth vessel in an atmosphere of nitrogen-containing gas, and causing the group-III element and nitrogen to react with each other in a melt of the group-III element, the alkali metal and the nitrogen so that a group-III element nitride crystal is grown using the seed crystal as a nucleus. A hydrocarbon having a boiling point higher than the melting point of the alkali metal is added before the pressurization and heating of the crystal growth vessel.

Abstract: A method for producing a GaN crystal capable of achieving at least one of the prevention of nucleation and the growth of a high-quality non-polar surface is provided. The production method of the present invention is a method for producing a GaN crystal in a melt containing at least an alkali metal and gallium, including an adjustment step of adjusting the carbon content of the melt, and a reaction step of causing the gallium and nitrogen to react with each other. According to the production method of the present invention, nucleation can be prevented, and as shown in FIG. 4, a non-polar surface can be grown.

Abstract: A nitride single crystal is produced on a seed crystal substrate 5 in a melt containing a flux and a raw material of the single crystal in a growing vessel 1. The melt 2 in the growing vessel 1 has temperature gradient in a horizontal direction. In growing a nitride single crystal by flux method, adhesion of inferior crystals onto the single crystal is prevented and the film thickness of the single crystal is made constant.

Abstract: It is provided a melt composition for growing a gallium nitride single crystal by flux method. The melt composition contains gallium, sodium and barium, and a content of barium is 0.05 to 0.3 mol % with respect to 100 mol % of sodium.

Abstract: A production method is provided that enables to produce a large-sized bulk silicon carbide (SiC) crystal of high quality at low cost. A large-sized bulk silicon carbide (SiC) crystal of high quality can be obtained at a lower temperature by reacting silicon (Si) and carbon (C) produced from a lithium carbide such as dilithium acetylide (Li2C2) with each other in an alkali metal melt and thereby producing or growing a silicon carbide (SiC) crystal. FIG. 17 shows a high-resolution TEM (HR-TEM) image of the resultant 2H—SiC crystal. A preferable lithium carbide is dilithium acetylide (Li2C2). A preferable alkali metal melt is a melt of lithium alone.

Abstract: In the flux method, a source nitrogen gas is sufficiently heated before feeding to an Na—Ga mixture. The apparatus of the invention is provided for producing a group III nitride based compound semiconductor The apparatus includes a reactor which maintains a group III metal and a metal differing from the group III metal in a molten state, a heating apparatus for heating the reactor, an outer vessel for accommodating the reactor and the heating apparatus, and a feed pipe for feeding a gas containing at least nitrogen from the outside of the outer vessel into the reactor. The feed pipe has a zone for being heated together with the reactor by means of the heating apparatus, wherein the zone is heated inside the outer vessel and outside the reactor.