Abstract: Disclosed is a photovoltaic device comprising a substrate composed of an oriented polycrystalline zinc oxide sintered body in a plate shape, a photovoltaic layer provided on the substrate, and an electrode provided on the photovoltaic layer. According to the present invention, a photovoltaic device having high photoelectric conversion efficiency can be inexpensively provided.

Abstract: In the case that a functional layer, made of a nitride of a group 13 element, is formed on a composite substrate including a sapphire body and a gallium nitride crystal layer disposed over the sapphire body, the deviation of the function is prevented. The composite substrate 4 includes a sapphire body 1A and a gallium nitride crystal layer 3 disposed over the sapphire body. Aa warpage of the composite substrate is in a range of not less than +40 ?m and not more than +80 ?m per 5.08 cm in length.

Abstract: Provided is a zinc oxide-based sputtering target capable of improving the film formation rate while suppressing arcing in the formation of a zinc oxide-based transparent conductive film by sputtering. This zinc oxide-based sputtering target includes a zinc oxide-based sintered body mainly including zinc oxide crystal grains, and has a degree of (002) orientation of 50% or greater at a sputtering surface and a density of 5.30 g/cm3 or greater.

Abstract: Provided is a surface light-emitting device comprising a substrate composed of an oriented polycrystalline zinc oxide sintered body in a plate shape, a light emitting functional layer provided on the substrate, and an electrode provided on the light emitting functional layer. According to the present invention, a surface light-emitting device having high luminous efficiency can be inexpensively provided.

Abstract: In a substrate having a gallium nitride layer, surface damage after surface treatment of the gallium nitride layer is reduced and quality of a functional device formed thereon is improved. A substrate 4 having at least a gallium nitride layer 4 is provided. A plasma etching system equipped with an inductively coupled plasma generating system is used and a fluorine-based gas is introduced at a standardized direct current bias potential of ?10V/cm2 or higher to subject a surface 3a of the gallium nitride layer to dry etching treatment.

Abstract: Provided is a self-supporting gallium nitride substrate useful as an alternative material for a gallium nitride single crystal substrate, which is inexpensive and also suitable for having a large area. This substrate is composed of a plate composed of gallium nitride-based single crystal grains, wherein the plate has a single crystal structure in the approximately normal direction. This substrate can be manufactured by a method comprising providing an oriented polycrystalline sintered body; forming a seed crystal layer composed of gallium nitride on the sintered body so that the seed crystal layer has crystal orientation mostly in conformity with the crystal orientation of the sintered body; forming a layer with a thickness of 20 ?m or greater composed of gallium nitride-based crystals on the seed crystal layer so that the layer has crystal orientation mostly in conformity with crystal orientation of the seed crystal layer; and removing the sintered body.

Abstract: The present invention provides a zinc oxide powder that enables a high degree of orientation, and highly uniform dispersion of an additive substance, to be simultaneously achieved in a green body or a sintered body. The zinc oxide powder of the present invention comprises a plurality of plate-like zinc oxide particles and has a volume-based D50 average particle diameter of 1 to 5 ?m and a specific surface area of 1 to 5 m2/g. The zinc oxide powder has a degree of orientation of the (002) plane of 40% or greater when two-dimensionally arrayed into a monolayer on a substrate.

Abstract: A growth apparatus is used having a plurality of crucibles 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: The present invention provides a method capable of stably producing a zinc oxide single crystal in which a large amount of dopant forms a solid solution at a high level of productivity and reproducibility without using a harmful substance. The method of the present invention comprises providing a raw material powder that is mainly composed of zinc oxide, comprises at least one dopant element selected from B, Al, Ga, In, C, F, Cl, Br, I, H, Li, Na, K, N, P, As, Cu, and Ag in a total amount of 0.01 to 1 at %, and is substantially free of a crystal phase other than zinc oxide, and injecting the raw material powder to form a film mainly composed of zinc oxide on a seed substrate comprising a zinc oxide single crystal and also to crystallize the formed film in a solid phase state.

Abstract: Provided is a zinc oxide sputtering target, which can effectively suppress the occurrence of break or crack in the target during sputtering to enable production of a zinc oxide transparent conductive film with high productivity. The zinc oxide sputtering target is composed of a zinc oxide sintered body comprising zinc oxide crystal grains, wherein the zinc oxide sputtering target has a sputter surface having a (100) crystal orientation degree of 50% or more.

Abstract: A gallium nitride layer is produced using a seed crystal substrate by flux method. The seed crystal substrate 8A includes a supporting body 1, a plurality of seed crystal layers 4A each comprising gallium nitride single crystal and separated from one another, a low temperature buffer layer 2 provided between the seed crystal layers 4A and the supporting body and made of a nitride of a group III metal element, and an exposed layer 3 exposed to spaces between the adjacent seed crystal layers 4A and made of aluminum nitride single crystal or aluminum gallium nitride single crystal. The gallium nitride layer is grown on the seed crystal layers by flux method.

Abstract: To grow a gallium nitride crystal, a seed-crystal substrate is first immersed in a melt mixture containing gallium and sodium. Then, a gallium nitride crystal is grown on the seed-crystal substrate under heating the melt mixture in a pressurized atmosphere containing nitrogen gas and not containing oxygen. At this time, the gallium nitride crystal is grown on the seed-crystal substrate under a first stirring condition of stirring the melt mixture, the first stirring condition being set for providing a rough growth surface, and the gallium nitride crystal is subsequently grown on the seed-crystal substrate under a second stirring condition of stirring the melt mixture, the second stirring condition being set for providing a smooth growth surface.

Abstract: A seed crystal substrate 10 includes a supporting body 1, and a seed crystal film 3A formed on the supporting body 1 and composed of a single crystal of a nitride of a Group 13 metal element. The seed crystal film 3A includes main body parts 3a and thin parts 3b having a thickness smaller than that of the main body parts 3a. The main body parts 3a and thin part 3b are exposed to a surface of the seed crystal substrate 10. A nitride 15 of a Group 13 metal element is grown on the seed crystal film 3A by flux method.

Abstract: A gallium nitride layer is produced using a seed crystal substrate by flux method. The seed crystal substrate 8A includes a supporting body 1, a plurality of seed crystal layers 4A each comprising gallium nitride single crystal and separated from one another, a low temperature buffer layer 2 provided between the seed crystal layers 4A and the supporting body and made of a nitride of a group III metal element, and an exposed layer 3 exposed to spaces between the adjacent seed crystal layers 4A and made of aluminum nitride single crystal or aluminum gallium nitride single crystal. The gallium nitride layer is grown on the seed crystal layers by flux method.

Abstract: A crystal production method according to the present invention includes a film formation and crystallization step of spraying a raw material powder containing a raw material component to form a film containing the raw material component on a seed substrate containing a single crystal at a predetermined single crystallization temperature at which single crystallization of the raw material component occurs, and crystallizing the film containing the raw material while maintaining the single crystallization temperature. In the film formation and crystallization step, preferably, the single crystallization temperature is 900° C. or higher. Furthermore, in the film formation and crystallization step, preferably, the raw material powder and the seed substrate are each a nitride or an oxide.

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: An object of the present invention is to realize, by the flux process, the production of a high-quality n-type semiconductor crystal having high concentration of electrons. The method of the invention for producing an n-type Group III nitride-based compound semiconductor by the flux process, the method including preparing a melt by melting at least a Group III element by use of a flux; supplying a nitrogen-containing gas to the melt; and growing an n-type Group III nitride-based compound semiconductor crystal on a seed crystal from the melt. In the method, carbon and germanium are dissolved in the melt, and germanium is incorporated as a donor into the semiconductor crystal, to thereby produce an n-type semiconductor crystal. The mole percentage of germanium to gallium in the melt is 0.05 mol % to 0.5 mol %, and the mole percentage of carbon to sodium is 0.1 mol % to 3.0 mol %.

Abstract: A raw material mixture containing an easily oxidizable material is weighed. The raw material mixture is melted and then solidified within a reaction vessel 1 set in a non-oxidizing atmosphere to thereby produce a solidified matter 19. The reaction vessel 1 and the solidified matter 19 are heated in a non-oxidizing atmosphere within a crystal growth apparatus to melt the solidified matter to thereby produce a solution. A single crystal is grown from the solution.

Abstract: To grow a gallium nitride crystal, a seed-crystal substrate is first immersed in a melt mixture containing gallium and sodium. Then, a gallium nitride crystal is grown on the seed-crystal substrate under heating the melt mixture in a pressurized atmosphere containing nitrogen gas and not containing oxygen. At this time, the gallium nitride crystal is grown on the seed-crystal substrate under a first stirring condition of stirring the melt mixture, the first stirring condition being set for providing a rough growth surface, and the gallium nitride crystal is subsequently grown on the seed-crystal substrate under a second stirring condition of stirring the melt mixture, the second stirring condition being set for providing a smooth growth surface.

Abstract: In the production of GaN through the flux method, deposition of miscellaneous crystals on the nitrogen-face of a GaN self-standing substrate and waste of raw materials are prevented. Four arrangements of crucibles and a GaN self-standing substrate are exemplified. In FIG. 1A, a nitrogen-face of a self-standing substrate comes into close contact with a sloped flat inner wall of a crucible. In FIG. 1B, a nitrogen-face of a self-standing substrate comes into close contact with a horizontally facing flat inner wall of a crucible, and the substrate is fixed by means of a jig. In FIG. 1C, a jig is provided on a flat bottom of a crucible, and two GaN self-standing substrates are fixed by means of the jig so that the nitrogen-faces of the substrates come into close contact with each other. In FIG. 1D, a jig is provided on a flat bottom of a crucible, and a GaN self-standing substrate is fixed on the jig so that the nitrogen-face of the substrate is covered with the jig.