Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: Provided are: a GaN crystal used in a substrate for a nitride semiconductor device having a horizontal device structure, such as a GaN-HEMT; and a GaN substrate used for the production of a nitride semiconductor device having a horizontal device structure, such as a GaN-HEMT. The GaN crystal and the GaN substrate each include a surface having an inclination of 10° or less from a (0001) crystal plane and an area of 5 cm2 or more, and have an Mn concentration of 1.0 × 1016 atoms/cm3 or higher but lower than 1.0 × 1019 atoms/cm3 and a total donor impurity concentration of lower than 5.0 × 1016 atoms/cm3.

Abstract: A gallium nitride substrate comprising a first main surface and a second main surface opposite thereto, wherein the first main surface is a non-polar or semi-polar plane, a dislocation density measured by a room-temperature cathode luminescence method in the first main surface is 1×104 cm?2 or less, and an averaged dislocation density measured by a room-temperature cathode luminescence method in an optional square region sizing 250 ?m×250 ?m in the first main plan is 1×106 cm?2 or less.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: A method for producing a GaN crystal is provided. In the method, front surfaces of a plurality of tiling GaN seeds closely arranged side by side on a flat surface of a plate are planarized. An aggregated seed is formed by arranging the tiling GaN seeds closely side by side on a susceptor of an HVPE apparatus in the same arrangement as when fixed on the plate, with the front planarized surfaces facing upward. A bulk GaN crystal is grown epitaxially on the aggregated seed by an HVPE method.

Abstract: Strain is used to enhance the properties of p- and n-materials so as to improve the performance of III-N electronic and optoelectronic devices. In one example, transistor devices include a channel aligned along uniaxially strained or relaxed directions of the III-nitride material in the channel. Strain is introduced using buffer layers or source and drain regions of different composition.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: Provided is a rotary electric machine including: a permanent magnet rotatable around a first rotational shaft and disposed at a distance from a main surface of a moving body rotating or moving, at least a part of a side surface of the permanent magnet continuous to an outer peripheral surface thereof being opposed to the main surface of the moving body, wherein the permanent magnet is rotated around the first rotational shaft by a reaction force acting on the permanent magnet, the reaction force being caused by eddy currents produced in the main surface of the moving body in such a direction as to hinder a change of magnetic flux from the permanent magnet, and a surface speed of the side surface of the permanent magnet opposed to the moving body is lower than a surface speed of the main surface of the moving body opposed thereto.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10 ?5 ? or less is observed.

Abstract: A gallium nitride substrate comprising a first main surface and a second main surface opposite thereto, wherein the first main surface is a non-polar or semi-polar plane, a dislocation density measured by a room-temperature cathode luminescence method in the first main surface is 1×104 cm?2 or less, and an averaged dislocation density measured by a room-temperature cathode luminescence method in an optional square region sizing 250 ?m×250 ?m in the first main plan is 1×106 cm?2 or less.

Abstract: The main purpose of the present invention is to provide: a nonpolar or semipolar GaN substrate, in which a nitride semiconductor crystal having a low stacking fault density can be epitaxially grown on the main surface of the substrate, and a technique required for the production of the substrate. This invention provides: a method for manufacturing an M-plane GaN substrate comprising; forming a mask pattern having a line-shaped opening parallel to an a-axis of a C-plane GaN substrate on an N-polar plane of the C-plane GaN substrate, growing a plane-shape GaN crystal of which thickness direction is an m-axis direction from the opening of the mask pattern by an ammonotharmal method, and cutting out the M-plane GaN substrate from the plane-shape GaN crystal.

Abstract: A disc-like GaN substrate is a substrate produced by a tiling method and having an angel between the normal line and m-axis on the main surface of the substrate of 0 to 20° inclusive and a diameter of 45 to 55 mm, to 4 or less. In a preferred embodiment, a disc-like GaN substrate has a first main surface and a second main surface that is opposite to the first main surface, and which has an angle between the normal line and m-axis on the first main surface of 0 to 20° inclusive and a diameter of 45 mm or more. The disc-like GaN substrate comprises at least four crystalline regions each being exposed to both of the first main surface and the second main surface, wherein the four crystalline regions are arranged in line along the direction of the orthogonal projection of c-axis on the first main surface.

Abstract: A disk-shaped GaN substrate has a diameter of 2 inches or more has a front surface tilted with a tilt angle of 45° or more and 135° or less relative to the (0001) plane in a tilt direction within a range of ±5° around the <10-10> direction, and a back surface which is a main surface opposite to the front surface. The GaN substrate has a first point positioned in a direction perpendicular to the c-axis when viewed from the center thereof, on the side surface thereof. A single diffraction peak appears in an X-ray diffraction pattern obtained by ? scan in which an X-ray (CuK?1: wavelength: 0.1542 nm) is incident to the first point and the incident angle ? of the incident X-ray is varied while the 2? angle of the diffracted X-ray is fixed to twice the Bragg angle of 28.99° of the {11-20} plane.

Abstract: A method for producing a GaN crystal is provided. In the method, front surfaces of a plurality of tiling GaN seeds closely arranged side by side on a flat surface of a plate are planarized. An aggregated seed is formed by arranging the tiling GaN seeds closely side by side on a susceptor of an HVPE apparatus in the same arrangement as when fixed on the plate, with the front planarized surfaces facing upward. A bulk GaN crystal is grown epitaxially on the aggregated seed by an HVPE method.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: A non-contact power generator includes: a magnet disposed at a distance to a main surface of a moving body that moves in one direction and the opposite direction, and the magnet generating a magnetic flux passing the main surface; a coil being separated from a surface of the magnet that faces away from the main surface, the coil being linked with the magnetic flux from the magnet; and a magnetic flux guide member disposed in a part of a magnetic path of the magnetic flux linked with the coil. The magnet is moved along the shaft in the moving direction of the moving body at a speed lower than the speed of the moving body by a reaction force acting on the magnet on a basis of eddy currents generated in the main surface in such a direction as to hinder a change of the magnetic flux from the magnet.

Abstract: A disc-like GaN substrate is a substrate produced by a tiling method and having an angel between the normal line and m-axis on the main surface of the substrate of 0 to 20° inclusive and a diameter of 45 to 55 mm, to 4 or less. In a preferred embodiment, a disc-like GaN substrate has a first main surface and a second main surface that is opposite to the first main surface, and which has an angle between the normal line and m-axis on the first main surface of 0 to 20° inclusive and a diameter of 45 mm or more. The disc-like GaN substrate comprises at least four crystalline regions each being exposed to both of the first main surface and the second main surface, wherein the four crystalline regions are arranged in line along the direction of the orthogonal projection of c-axis on the first main surface.