Abstract: Disclosed is a technique capable of preventing occurrence of warping in a nitride compound semiconductor layer, and by which a nitride compound semiconductor layer having small variations in the in-plane off angle can be grown with good reproducibility. Specifically disclosed is a method for producing a nitride compound semiconductor substrate using an HVPE process, wherein a low-temperature protective layer is formed on a rare earth perovskite substrate at a first growth temperature (a first step), and a thick layer composed of a nitride compound semiconductor is formed on the low-temperature protective layer at a second growth temperature that is higher than the first growth temperature (a second step). In the first step, the supply amounts of HCl and NH3 are controlled so that the supply ratio of HCl to NH3, namely the supply ratio III/V is 0.016-0.13, and the low-temperature protective layer has a film thickness of 50-90 nm.

Abstract: An epitaxial growth method forming a semiconductor thin film including a heterojunction of a group III-V compound semiconductor by means of molecular beam epitaxy. The method is configured to include: a first step of irradiating a molecular beam of at least one of group III elements and a molecular beam of a first group V element to form a first compound semiconductor layer; a second step of stopping the irradiation of the molecular beam of the group III element and the molecular beam of the first group V element to halt growth until an amount of the first group V element supplied is reduced to 1/10 or less of a supply of the first group V element in the first step; and a third step of irradiating a molecular beam of at least one of the group III elements and a molecular beam of a second group V element to form a second compound semiconductor layer, which is different from the first compound semiconductor, on the first compound semiconductor layer.

Abstract: Provided are a manufacturing method of a GaN single crystal in which the film thickness of the GaN single crystal can be controlled accurately, even when a hydride vapor phase epitaxy is applied; a GaN thin film template substrate which is suitable for growing a GaN thick film with a fine property; and a GaN single crystal growing apparatus. Provided is a manufacturing method of a GaN single crystal by a hydride vapor phase epitaxy, wherein the hydride vapor phase epitaxy comprises: spraying HCl (hydrogen chloride) onto Ga (gallium) which is heated and fused in a predetermined temperature to generate GaCl (gallium chloride); and forming a GaN thin film by a reaction of the generated GaCl (gallium chloride) with NH3 (ammonia) gas which is hydroxide gas on a substrate, the manufacturing method comprising supplying the NH3 gas in a vicinity of the substrate (for example, at a position which is separated from the substrate by a distance of 0.7-4.

Abstract: A low-temperature protective layer having AlN is grown on a rare earth perovskite substrate and a first GaN based semiconductor layer having Alx1Ga1-x1N where composition x1 of Al is 0.40?x1?0.45 is grown thereon. Then, a second GaN semiconductor layer having Alx2Ga1-x2N where composition x2 of Al is 0?x2?0.45 is grown on the first GaN based semiconductor layer.

Abstract: Provided is a technique for stabilizing characteristics of an NdGaO3 substrate used for epitaxial growth so as to grow a fine nitride compound semiconductor single crystal with good reproducibility. A single crystal of NdGaO3 grown by a crystal pulling method is subjected to an annealing treatment at 1400° C. or more and 1500° C. or less for a predetermined time period (for example, 10 hours) in the air, and this annealed NdGaO3 substrate is used as a substrate for epitaxial growth.

Abstract: Provided are a manufacturing method of a GaN single crystal in which the film thickness of the GaN single crystal can be controlled accurately, even when a hydride vapor phase epitaxy is applied; a GaN thin film template substrate which is suitable for growing a GaN thick film with a fine property; and a GaN single crystal growing apparatus. Provided is a manufacturing method of a GaN single crystal by a hydride vapor phase epitaxy, wherein the hydride vapor phase epitaxy comprises: spraying HCl (hydrogen chloride) onto Ga (gallium) which is heated and fused in a predetermined temperature to generate GaCl (gallium chloride); and forming a GaN thin film by a reaction of the generated GaCl (gallium chloride) with NH3 (ammonia) gas which is hydroxide gas on a substrate, the manufacturing method comprising supplying the NH3 gas in a vicinity of the substrate (for example, at a position which is separated from the substrate by a distance of 0.7-4.

Abstract: An epitaxial growth method forming a semiconductor thin film including a heterojunction of a group III-V compound semiconductor by means of molecular beam epitaxy. The method is configured to include: a first step of irradiating a molecular beam of at least one of group III elements and a molecular beam of a first group V element to form a first compound semiconductor layer; a second step of stopping the irradiation of the molecular beam of the group III element and the molecular beam of the first group V element to halt growth until an amount of the first group V element supplied is reduced to 1/10 or less of a supply of the first group V element in the first step; and a third step of irradiating a molecular beam of at least one of the group III elements and a molecular beam of a second group V element to form a second compound semiconductor layer, which is different from the first compound semiconductor, on the first compound semiconductor layer.