Abstract: A manufacturing apparatus of Group III nitride crystals and a method for manufacturing Group III nitride crystals are provided, by which high quality crystals can be manufactured. For instance, crystals are grown using the apparatus of the present invention as follows. A crystal raw material (131) and gas containing nitrogen are introduced into a reactor vessel (120), to which heat is applied by a heater (110), and crystals are grown in an atmosphere of pressure applied thereto. The gas is introduced from a gas supplying device (180) to the reactor vessel (120) through a gas inlet of the reactor vessel, and then is exhausted to the inside of a pressure-resistant vessel (102) through a gas outlet of the reactor vessel. Since the gas is introduced directly to the reactor vessel (120) without passing through the pressure-resistant vessel (102), the mixture of impurities attached to the pressure-resistant vessel (102) and the like into the site of the crystal growth can be prevented.

Abstract: The present invention provides a method of manufacturing a gallium nitride single crystal that can suppress the decomposition of gallium nitride and improve production efficiency in a sublimation method. According to the manufacturing method, a material (GaN powder) for the gallium nitride (GaN) single crystal is placed inside a crucible, sublimed or evaporated by heating, and cooled on a substrate surface to return to a solid again, so that the gallium nitride single crystal is grown on the substrate surface. The growth of the single crystal is performed under pressure. The pressure is preferably not less than 5 atm (5×1.013×105 Pa). The single crystal is grown preferably in a mixed gas atmosphere containing NH3 and N2.

Abstract: A method of manufacturing a group III-nitride crystal substrate including the steps of introducing an alkali-metal-element-containing substance, a group III-element-containing substance and a nitrogen-element-containing substance into a reactor, forming a melt containing at least the alkali metal element, the group III-element and the nitrogen element in the reactor, and growing group III-nitride crystal from the melt, and characterized by handling the alkali-metal-element-containing substance in a drying container in which moisture concentration is controlled to at most 1.0 ppm at least in the step of introducing the alkali-metal-element-containing substance into the reactor is provided. A group III-nitride crystal substrate attaining a small absorption coefficient and the method of manufacturing the same, as well as a group III-nitride semiconductor device can thus be provided.

Abstract: An object of the present invention is to provide a novel method of growing hexagonal boron nitride single crystal. It is found that hexagonal boron nitride single crystal is grown in calcium nitride flux by heating, or heating and then slowly cooling, boron nitride and calcium series material in atmosphere containing nitrogen. Bulk of hexagonal boron nitride single crystal can thereby successfully be grown.

Abstract: A method of manufacturing a group III-nitride crystal substrate including the steps of introducing an alkali-metal-element-containing substance, a group III-element-containing substance and a nitrogen-element-containing substance into a reactor, forming a melt containing at least the alkali metal element, the group III-element and the nitrogen element in the reactor, and growing group III-nitride crystal from the melt, and characterized by handling the alkali-metal-element-containing substance in a drying container in which moisture concentration is controlled to at most 1.0 ppm at least in the step of introducing the alkali-metal-element-containing substance into the reactor is provided. A group III-nitride crystal substrate attaining a small absorption coefficient and the method of manufacturing the same, as well as a group III-nitride semiconductor device can thus be provided.

Abstract: The present invention provides a method of manufacturing Group III nitride crystals that are of high quality, are manufactured highly efficiently, and are useful and usable as a substrate that is used in semiconductor manufacturing processes.

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: There is provided a method of manufacturing a group-III nitride crystal in which a nitrogen plasma is brought into contact with a melt containing a group-III element and an alkali metal to grow the group-III nitride crystal. Furthermore, there is also provided a method of manufacturing a group-III nitride crystal in which the group-III nitride crystal is grown on a substrate placed in a melt containing a group-III element and an alkali metal, with a minimal distance between a surface of the melt and a surface of the substrate set to be at most 50 mm.

Abstract: The present invention provides a manufacturing method in which high quality GaN crystals and GaN crystal substrates can be manufactured under mild conditions of low pressure and low temperature. In a method of manufacturing GaN crystals in which in a gas atmosphere containing nitrogen, gallium and the nitrogen are allowed to react with each other to generate GaN crystals in a mixed melt of the gallium and sodium, the gallium and the nitrogen are allowed to react with each other under a pressurizing condition that exceeds atmospheric pressure, and pressure P1 (atm(×1.013×105 Pa)) of the pressurizing condition is set so as to satisfy the condition that is expressed by the following conditional expression (I): P?P1<(P+45),??(I) where in the expression (I), P (atm(×1.013×105 Pa)) denotes the minimum pressure that is required for generating GaN crystals at a temperature T° C. of the mixed melt.

Abstract: The present invention provides a producing method with which large silicon carbide (SiC) single crystal can be produced at low cost. Silicon carbide single crystal is produced or grown by dissolving and reacting silicon (Si) and carbon (C) in an alkali metal flux. The alkali metal preferably is lithium (Li). With this method, silicon carbide single crystal can be produced even under low-temperature conditions of 1500° C. or lower, for example. The photograph of FIG. 3B is an example of a silicon carbide single crystal obtained by the method of the present invention.

Abstract: The present invention provides a method for producing a compound single crystal that can improve a growth rate and grow a large single crystal with high crystal uniformity in a short time, and a production apparatus used for the method. The compound single crystal is grown while stirring a material solution to create a flow from a gas-liquid interface in contact with a source gas toward the inside of the material solution. With this stirring, the source gas can be dissolved easily in the material solution, and supersaturation can be achieved in a short time, thus improving the growth rate of the compound single crystal. Moreover, the flow formed by the stirring goes from the gas-liquid interface where a source gas concentration is high to the inside of the material solution where the source gas concentration is low, so that dissolution of the source gas becomes uniform.

Abstract: In a nitrogen-containing atmosphere, a Group III nitride crystal is grown in a flux that includes at least one Group III element selected from Ga, Al, and In, an alkali metal, and Mg, thereby forming a Group III nitride substrate. Since Mg is a p-type dopant for the Group III nitride crystal, even if Mg is present in the crystal, the crystal can have p-type or semi-insulating electrical characteristics and causes no problem in its application to an electronic device. Moreover, the amount of nitrogen dissolved in the flux is increased because the flux includes Mg, which allows the crystal to be grown at a high growth rate and also improves the reproducibility of the crystal growth.

Abstract: The present invention provides a method of manufacturing Group III nitride crystals that are of high quality, are manufactured efficiently, and are useful and usable as a substrate for semiconductor manufacturing processes. A semiconductor layer that is made of a semiconductor and includes crystal-nucleus generation regions at its surface is formed. The semiconductor is expressed by a composition formula of AluGavIn1-u-vN (where 0?u?1, 0?v?1, and u+v?1). Group III nitride crystals then are grown on the semiconductor layer by bringing the crystal-nucleus generation regions of the semiconductor layer into contact with a melt in an atmosphere including nitrogen. The melt contains nitrogen, at least one Group III element selected from the group consisting of gallium, aluminum, and indium, and at least one of alkali metal and alkaline-earth metal.

Abstract: The present invention relates to a process for producing high-quality crystals of protein or organic substances easily and efficiently. A solution of protein or an organic substance is prepared and then is cooled slowly to be supersaturated to a low degree. This supersaturated solution is irradiated with a femtosecond laser 10. A local explosion phenomenon occurs at the focal point of the laser and thereby a crystalline nucleus is generated. A high-quality crystal is obtained when a crystal is grown on the crystalline nucleus over a long period of time. The femtosecond laser to be used herein can be a titanium:sapphire laser having a wavelength of 800 nm, a duration of 120 fs, a frequency of 1 kHz, and an output of 400 mW.

Abstract: A manufacturing apparatus of Group III nitride crystals and a method for manufacturing Group III nitride crystals are provided, by which high quality crystals can be manufactured. For instance, crystals are grown using the apparatus of the present invention as follows. A crystal raw material (131) and gas containing nitrogen are introduced into a reactor vessel (120), to which heat is applied by a heater (110), and crystals are grown in an atmosphere of pressure applied thereto. The gas is introduced from a gas supplying device (180) to the reactor vessel (120) through a gas inlet of the reactor vessel, and then is exhausted to the inside of a pressure-resistant vessel (102) through a gas outlet of the reactor vessel. Since the gas is introduced directly to the reactor vessel (120) without passing through the pressure-resistant vessel (102), the mixture of impurities attached to the pressure-resistant vessel (102) and the like into the site of the crystal growth can be prevented.

Abstract: The present invention provides a method for producing a Group III nitride compound semiconductor crystal, the semiconductor crystal being grown through the flux method employing a flux. At least a portion of a substrate on which the semiconductor crystal is to be grown is formed of a flux-soluble material. While the semiconductor crystal is grown on a surface of the substrate, the flux-soluble material is dissolved in the flux from a surface of the substrate that is opposite the surface on which the semiconductor crystal is grown. Alternatively, after the semiconductor crystal has been grown on a surface of the substrate, the flux-soluble material is dissolved in the flux from a surface of the substrate that is opposite the surface on which the semiconductor crystal has been grown. The flux-soluble material is formed of silicon.

Abstract: The present invention provides a cesium-lithium-borate crystal, which can be used as a high-performance wavelength converting crystal, having a chemical composition expressed as CsLiB6O10, and substituted cesium-lithium-borate crystals expressed by the following formula: Cs1?xLi1?yMx+yB6O10 or Cs2(1?z)Li2LzB12O20 (where, M is an alkali metal element, and L is an alkali earth metal element); a method for manufacturing same by heating and melting; and an optical apparatus using such crystals.

Abstract: The present invention provides a manufacturing method that allows a Group III nitride substrate with a low dislocation density to be manufactured, and a semiconductor device that is manufactured using the manufacturing method. The manufacturing method includes, in an atmosphere including nitrogen, allowing a Group III element and the nitrogen to react with each other in an alkali metal melt to cause generation and growth of Group III nitride crystals. In the manufacturing method, a plurality of portions of a Group III nitride semiconductor layer are prepared, selected as seed crystals, and used for at least one of the generation and the growth of the Group III nitride crystals, and then surfaces of the seed crystals are brought into contact with the alkali metal melt.

Abstract: In a wavelength converting method, an ambient that is in contact with a surface of a non-linear optical crystal from which wavelength-converted light is outputted is a gas that is lower in content of nitrogen than air. A wavelength converting device includes a device for controlling the ambient in contact with a surface of the non-linear optical crystal from which the wavelength-converted light is outputted so the ambient is lower in nitrogen than air. A laser machining device includes the wavelength converting device.

Abstract: The present invention provides a Group III nitride crystal substrate whose surface has concavities and convexities reduced in size. The surfaces with concavities and convexities, such as hillocks, pits and facets, of Group III nitride crystals are brought into contact with a melt and thereby the surfaces are subjected to meltback etching or mechanochemical polishing. The melt includes at least one of alkali metal and alkaline-earth metal. Thus a Group III nitride crystal substrate that has reduced strain and a reduced number of defects, which are caused through the processing, and is excellent in surface flatness is manufactured. Furthermore, by the use of the Group III nitride crystal substrate of the present invention, for instance, semiconductor devices of high performance can be obtained.