Abstract: A free-standing substrate of a polycrystalline nitride of a group 13 element contains a plurality of monocrystalline particles having a particular crystal orientation in approximately a normal direction. The polycrystalline nitride of the group 13 element is composed of gallium nitride, aluminum nitride, indium nitride or a mixed crystal thereof. The free-standing substrate has a top surface and bottom surface. The free-standing substrate contains at least one of zinc and calcium. A root mean square roughness Rms at the top surface is 3.0 nm or less.

Abstract: A free-standing substrate of a polycrystalline nitride of a group 13 element is composed of a plurality of monocrystalline particles having a particular crystal orientations in approximately a normal direction. The free-standing substrate has a top surface and a bottom surface. The polycrystalline nitride of the group 13 element is gallium nitride, aluminum nitride, indium nitride or a mixed crystal thereof and contains zinc at a concentration of 1×1017 atoms/cm3 or more and 1×1020 atoms/cm3 or less.

Abstract: A device substrate in which no streaked morphological abnormality occurs is achieved. A GaN template substrate includes: a base substrate; and a first GaN layer epitaxially formed on the base substrate, wherein the first GaN layer has a compressive stress greater than or equal to 260 MPa that is intrinsic in an inplane direction, or a full width at half maximum of a peak representing E2 phonons of GaN near a wavenumber of 568 cm?1 in a Raman spectrum is lower than or equal to 1.8 cm?1. With all of these requirements, a device substrate includes: a second GaN layer epitaxially formed on the first GaN layer; and a device layer epitaxially formed on the second GaN layer and made of a group 13 nitride.

Abstract: A heat discharge structure that includes a film of a nitride of a group 13 element having a first main face, a second main face and an outer side end face. The structure further includes a portion for containing the light source device. The portion has a through hole opening at the first main face and the second main face, and a fixing face for fixing the light source device. The fixing face faces the through hole and contacts the light source device.

Abstract: Provided is an epitaxial substrate for semiconductor elements which suppresses leakage current and has high breakdown voltage. An epitaxial substrate for semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN being doped with Zn; a buffer layer formed of group 13 nitride to be adjacent to the free-standing substrate; a channel layer formed of group 13 nitride to be adjacent to the buffer layer; and a barrier layer formed of group 13 nitride on an opposite side of the buffer layer with the channel layer therebetween, wherein part of a first region consisting of the free-standing substrate and the buffer layer is a second region containing Si at a concentration of 1×1017 cm?3 or more, and a minimum value of a concentration of Zn in the second region is 1×1017 cm?3.

Abstract: Provided is an epitaxial substrate for semiconductor elements which suppresses an occurrence of current collapse. The epitaxial substrate for the semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN being doped with Zn; a buffer layer being adjacent to the free-standing substrate; a channel layer being adjacent to the buffer layer; and a barrier layer being provided on an opposite side of the buffer layer with the channel layer therebetween, wherein the buffer layer is a diffusion suppressing layer that suppresses diffusion of Zn from the free-standing substrate into the channel layer.

Abstract: Provided is an epitaxial substrate for semiconductor elements which suppresses an occurrence of current collapse. The epitaxial substrate for the semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN being doped with Zn; a buffer layer being adjacent to the free-standing substrate; a channel layer being adjacent to the buffer layer; and a barrier layer being provided on an opposite side of the buffer layer with the channel layer therebetween, wherein the buffer layer is a diffusion suppressing layer formed of Al-doped GaN and suppresses diffusion of Zn from the free-standing substrate into the channel layer.

Abstract: Provided is an epitaxial substrate for semiconductor elements which suppresses an occurrence of current collapse. The epitaxial substrate for the semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN being doped with Zn; a buffer layer being adjacent to the free-standing substrate; a channel layer being adjacent to the buffer layer; and a barrier layer being provided on an opposite side of the buffer layer with the channel layer therebetween, wherein the buffer layer is a diffusion suppressing layer formed of AlpGa1-pN (0.7?p?1) and suppresses diffusion of Zn from the free-standing substrate into the channel layer.

Abstract: A composite substrate includes a polycrystalline ceramic substrate, a silicon substrate directly bonded to the polycrystalline ceramic substrate, a seed crystal film formed on the silicon substrate by vapor phase process and made of a nitride of a group 13 element, and a gallium nitride crystal layer grown on the seed crystal film by flux method.

Abstract: Provided are a group 13 nitride composite substrate allowing for the production of a semiconductor device suitable for high-frequency applications while including a conductive GaN substrate, and a semiconductor device produced using this substrate. The group 13 nitride composite substrate includes a base material of an n-conductivity type formed of GaN, a base layer located on the base material, being a group 13 nitride layer having a resistivity of 1×106 ?·cm or more, a channel layer located on the base layer, being a GaN layer having a total impurity density of 1×1017/cm3 or less, and a barrier layer that is located on the channel layer and is formed of a group 13 nitride having a composition AlxInyGa1?x?yN (0?x?1, 0?y?1).

Abstract: Provided is a self-supporting polycrystalline GaN substrate composed of GaN-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate. The crystal orientations of individual GaN-based single crystal grains as determined from inverse pole figure mapping by EBSD analysis on the substrate surface are distributed with tilt angles from the specific crystal orientation, the average tilt angle being 1 to 10°. There is also provided a light emitting device including the self-supporting substrate and a light emitting functional layer, which has at least one layer composed of semiconductor single crystal grains, the at least one layer having a single crystal structure in the direction approximately normal to the substrate. The present invention makes it possible to provide a self-supporting polycrystalline GaN substrate having a reduced defect density at the substrate surface, and to provide a light emitting device having a high luminous efficiency.

Abstract: A vertical external-cavity surface-emitting laser (VECSEL) whose blueshift is reduced also in a high intensity range of emitted laser light is realized. A surface-emitting device for VECSEL includes a base substrate made of GaN and c-axis oriented, and an emitter structure formed of a group 13 nitride semiconductor and provided on the base substrate. The emitter structure is formed of unit deposition parts, each of which is provided on the base substrate and includes a DBR layer having a distributed Bragg reflection structure and an active layer that has a multiple quantum well structure and generates excitation emission in response to irradiation with external laser light. A c-axis orientation of each of the unit deposition parts conforms to the c-axis orientation of the base substrate located directly below the unit deposition parts. Grooves are formed between the unit deposition parts.

Abstract: It is provided a heat discharge structure for a light source device emitting a semiconductor laser. The structure fixes the light source device and discharges heat. The structure includes a film of a nitride of a group 13 element having a first main face, a second main face and an outer side end face. The structure further includes a portion for containing the light source device. The portion has a through hole opening at the first main face and the second main face, and a fixing face for fixing the light source device. The fixing face faces the through hole and contacts the light source device.

Abstract: Provided is a group 13 nitride epitaxial substrate with which the HEMT device having superior characteristics can be manufactured. This epitaxial substrate is provided with: a base substrate composed of SiC and having a main surface with a (0001) plane orientation; a nucleation layer formed on one main surface of the base substrate and composed of AlN; an electron transit layer formed on the nucleation layer and composed of a group 13 nitride with the composition AlyGa1?yN (0?y<1); and a barrier layer formed on the electron transit layer and composed of a group 13 nitride with the composition InzAl1?zN (0.13?z?0.23) or AlwGa1?wN (0.15?w?0.35). The (0001) plane of the base substrate has an off angle of 0.1° or more and 0.5° or less, and an intermediate layer composed of a group 13 nitride with the composition AlxGa1?xN (0.01?x?0.4) is further provided between the nucleation layer and the electron transit layer.

Abstract: A method for manufacturing a light emitting device includes a) forming a first light confinement layer having a plurality of openings on or above one main surface of an oriented polycrystalline substrate, said oriented polycrystalline substrate including a plurality of oriented crystal grains; b) stacking an n-type layer, an active layer, and a p-type layer; c) forming a second light confinement layer on said first light confinement layer so that said second light confinement layer covers said plurality of first columnar structures and said second columnar structure; d) forming a transparent conductive film on said second light confinement layer; e) forming a pad electrode on said transparent conductive film; and f) forming a cathode electrode electrically connected to ends of said plurality of first columnar structures closer to said oriented polycrystalline substrate.

Abstract: A light emitting device that is inexpensive, is easy to manufacture, and has high light extraction efficiency is provided. The light emitting device includes an oriented polycrystalline substrate, a plurality of columnar light emitting parts, and a light confinement layer. The oriented polycrystalline substrate includes a plurality of oriented crystal grains. The plurality of columnar light emitting parts are discretely located on or above one main surface of the oriented polycrystalline substrate in areas in which there are no crystal defects, and are each a columnar part having a longitudinal direction matching a normal direction of the oriented polycrystalline substrate. The light confinement layer is made of a material having a lower refractive index than a material for the plurality of columnar light emitting parts, and is located on or above the oriented polycrystalline substrate so as to surround the plurality of columnar light emitting parts.

Abstract: The maximum value of peak intensities of cathode luminescence of a wavelength corresponding to a band gap of gallium nitride and in a measured visual field of 0.1 mm×0.1 mm is 140 percent or higher of an average value of the peak intensities of the cathode luminescence, provided that the peak intensities of the cathode luminescence are measured on a surface of the gallium nitride substrate.

Abstract: A method for manufacturing a light emitting device includes a) forming a first light confinement layer having a plurality of openings on or above one main surface of an oriented polycrystalline substrate, said oriented polycrystalline substrate including a plurality of oriented crystal grains; b) stacking an n-type layer, an active layer, and a p-type layer; c) forming a second light confinement layer on said first light confinement layer so that said second light confinement layer covers said plurality of first columnar structures and said second columnar structure; d) forming a transparent conductive film on said second light confinement layer; e) forming a pad electrode on said transparent conductive film; and f) forming a cathode electrode electrically connected to ends of said plurality of first columnar structures closer to said oriented polycrystalline substrate.

Abstract: Provided is a self-supporting polycrystalline GaN substrate composed of GaN-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate. The crystal orientations of individual GaN-based single crystal grains as determined from inverse pole figure mapping by EBSD analysis on the substrate surface are distributed with tilt angles from the specific crystal orientation, the average tilt angle being 1 to 10°. There is also provided a light emitting device including the self-supporting substrate and a light emitting functional layer, which has at least one layer composed of semiconductor single crystal grains, the at least one layer having a single crystal structure in the direction approximately normal to the substrate. The present invention makes it possible to provide a self-supporting polycrystalline GaN substrate having a reduced defect density at the substrate surface, and to provide a light emitting device having a high luminous efficiency.

Abstract: Provided are a group 13 nitride composite substrate allowing for the production of a semiconductor device suitable for high-frequency applications while including a conductive GaN substrate, and a semiconductor device produced using this substrate. The group 13 nitride composite substrate includes a base material of an n-conductivity type formed of GaN, a base layer located on the base material, being a group 13 nitride layer having a resistivity of 1×106 ?·cm or more, a channel layer located on the base layer, being a GaN layer having a total impurity density of 1×1017/cm3 or less, and a barrier layer that is located on the channel layer and is formed of a group 13 nitride having a composition AlxInyGa1-x-yN (0?x?1, 0?y?1).