Abstract: Provided is a luminescent wheel for a projector, which has a novel structure in which a phosphor layer is hard to break even if its thickness is reduced; a manufacturing method therefor; and a light emitting device for a projector. A luminescent wheel for a projector includes: a phosphor layer (11) which has a first principal surface (11a) and a second principal surface (11b) located on an opposite side to the first principal surface (11a) and is capable of being excited by the entry of excitation light to emit fluorescence; a first glass layer (12) provided on the first principal surface (11a) of the phosphor layer (11); and a second glass layer (13) provided on the second principal surface (11b) of the phosphor layer (11).

Abstract: Provided is a fluorescent wheel for a projector capable of increasing the luminescence intensity and a light-emitting device for a projector using the same. The fluorescent wheel for a projector includes: an annular transparent substrate (11) including a first principal surface (11a) located on a side where excitation light (1) enters and a second principal surface (11b) located on a side where the excitation light (1) exits; a phosphor layer (12) provided on the second principal surface (11b) of the transparent substrate (11) and including an inorganic binder and a phosphor dispersed in the inorganic binder; and a filter layer (13) provided on the first principal surface (11a) of the transparent substrate (11) or between the second principal surface (11b) of the transparent substrate (11) and the phosphor layer (12) and configured to transmit the excitation light (1) and reflect fluorescence (2) emitted from the phosphor layer (12).

Abstract: Provided is a fluorescent wheel for a projector capable of suppressing the heating of the phosphor layer and a light emitting device for a projector using the same. The fluorescent wheel for a projector includes: a phosphor layer (12); an annular ceramic substrate (11) which includes a first principal surface provided with the phosphor layer (12) and a second principal surface located on an opposite side to the first principal surface and has a higher thermal conductivity than the phosphor layer (12); and a reflective layer (13) provided on the second principal surface of the ceramic substrate (11).

Abstract: A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Abstract: Disclosed is a phosphor composite material which can be fired at low temperatures and enables to obtain a phosphor composite member which is excellent in weather resistance and reduced in deterioration after long use. Also disclosed is a phosphor composite member obtained by firing such a phosphor composite material. Specifically disclosed is a phosphor composite material composed of a glass powder and a phosphor powder, which is characterized in that the glass powder is composed of SnO—P2O5—B2O3 glass.

Abstract: Affords gallium nitride crystal growth methods, gallium nitride crystal substrates, epi-wafers, and methods of manufacturing the epi-wafers, that make it possible to curb cracking that occurs during thickness reduction operations on the crystal, and to grow gallium nitride crystal having considerable thickness. A gallium nitride crystal growth method in one aspect of the present invention is a method of employing a carrier gas, a gallium nitride precursor, and a gas containing silicon as a dopant, and by hydride vapor phase epitaxy (HVPE) growing gallium nitride crystal onto an undersubstrate. The gallium nitride crystal growth method is characterized in that the carrier-gas dew point during the gallium nitride crystal growth is ?60° C. or less.

Abstract: A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Abstract: Provided is a phosphor composite member having excellent thermal resistance, high color rendition, controllability of various chromaticities from a daylight color to a light bulb color, and high luminescence intensity. A phosphor composite member in which a sintered inorganic powder body layer containing a SnO—P2O5-based glass and an inorganic phosphor powder is formed on a surface of a ceramic base material, wherein upon irradiation with an excitation light, the ceramic base material and the sintered inorganic powder body layer emit different fluorescences having different wavelengths.

Abstract: To provide a wavelength conversion member having good surface accuracy and dimensional accuracy even when processed in various shapes, and a method for manufacturing the same. A method for manufacturing a wavelength conversion member, including the steps of: subjecting a preform made of a powder mixture containing a glass powder and an inorganic phosphor powder to heat treatment, thereby obtaining a sintered powder product; and re-press molding the sintered powder product with a die.

Abstract: Disclosed is a phosphor composite material which can be fired at low temperatures and enables to obtain a phosphor composite member which is excellent in weather resistance and reduced in deterioration after long use. Also disclosed is a phosphor composite member obtained by firing such a phosphor composite material. Specifically disclosed is a phosphor composite material composed of a glass powder and a phosphor powder, which is characterized in that the glass powder is composed of SnO—P2O5—B2O3 glass.

Abstract: Disclosed is a phosphor composite material which can be fired at low temperatures and enables to obtain a phosphor composite member which is excellent in weather resistance and reduced in deterioration after long use. Also disclosed is a phosphor composite member obtained by firing such a phosphor composite material. Specifically disclosed is a phosphor composite material composed of a glass powder and a phosphor powder, which is characterized in that the glass powder is composed of SnO—P2O5—B2O3 glass.

Abstract: A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Abstract: To provide a wavelength conversion member having good surface accuracy and dimensional accuracy even when processed in various shapes, and a method for manufacturing the same. A method for manufacturing a wavelength conversion member, including the steps of: subjecting a preform made of a powder mixture containing a glass powder and an inorganic phosphor powder to heat treatment, thereby obtaining a sintered powder product; and re-press molding the sintered powder product with a die.

Abstract: A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Abstract: A GaN crystal substrate has a crystal growth surface on which a crystal is grown, and a rear surface opposite to the crystal growth surface. The crystal growth surface has a roughness Ra(C)of at most 10 nm, and the rear surface has a roughness Ra(R) of at least 0.5 ?m and at most 10 ?m. A ratio Ra(R)/Ra(C) of the surface roughness Ra(R) to the surface roughness Ra(C) is at least 50. Thus, a GaN crystal substrate of which front and rear surfaces are distinguishable from each other is provided, without impairing the morphology of a semiconductor layer grown on the GaN crystal substrate.

Abstract: Disclosed is a phosphor composite material which can be fired at low temperatures and enables to obtain a phosphor composite member which is excellent in weather resistance and reduced in deterioration after long use. Also disclosed is a phosphor composite member obtained by firing such a phosphor composite material. Specifically disclosed is a phosphor composite material composed of a glass powder and a phosphor powder, which is characterized in that the glass powder is composed of SnO—P2O5—B2O3 glass.

Abstract: A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Abstract: A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Abstract: Affords gallium nitride crystal growth methods, gallium nitride crystal substrates, epi-wafers, and methods of manufacturing the epi-wafers, that make it possible to curb cracking that occurs during thickness reduction operations on the crystal, and to grow gallium nitride crystal having considerable thickness. A gallium nitride crystal growth method in one aspect of the present invention is a method of employing a carrier gas, a gallium nitride precursor, and a gas containing silicon as a dopant, and by hydride vapor phase epitaxy (HVPE) growing gallium nitride crystal onto an undersubstrate. The gallium nitride crystal growth method is characterized in that the carrier-gas dew point during the gallium nitride crystal growth is ?60° C. or less.

Abstract: The GaN facet growth method produces defect accumulating regions H on masks by forming a dotmask or a stripemask on an undersubstrate, growing GaN in a reaction furnace in vapor phase, inducing GaN crystals on exposed parts without covering the masks, inviting facets starting from verges of the masks and producing defect accumulating regions H on the mask. The defect accumulating regions H have four versions, that is, non (O), polycrystal (P), c-axis inclining single crystal (A) and orientation inversion (J). The best is the orientation inversion region (J). A sign of occurrence of the orientation inversion regions (J) is beaks of inversion orientation appearing on facets. GaN is grown on a masked undersubstrate by supplying a carbon material at a hydrocarbon partial pressure of 10 Pa to 5 kPa for 0.5 hour to 2 hour by an HVPE facet growth method without burying facets.