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: 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: 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: The invention provides 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 method for manufacturing an M-plane GaN substrate by 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 ammonothermal method, and cutting out the M-plane GaN substrate from the plane-shape GaN crystal.

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.