Mitsubishi Chemical Corporation

Masayuki Tashiro

Yusuke Tsukada

Tetsuharu Kajimoto

Yutaka Mikawa

Satoru Nagao

Hideo Fujisawa

Kenji Fujito

Kazunori Kamada

Takashi Fukada

Hideo Namita

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.

Non-polar or semi-polar GaN wafer

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&#xb0; 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&#xb0; 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.

GaN substrate, method for producing GaN substrate, method for producing GaN crystal, and method for manufacturing semiconductor device

A disk-shaped GaN substrate has a diameter of 2 inches or more has a front surface tilted with a tilt angle of 45&#xb0; or more and 135&#xb0; or less relative to the (0001) plane in a tilt direction within a range of &#xb1;5&#xb0; around the &#x3c;10-10&#x3e; 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 &#x3b8; scan in which an X-ray (CuK&#x3b1;: wavelength: 0.1542 nm) is incident to the first point and the incident angle &#x3b8; of the incident X-ray is varied while the 2&#x3b8; angle of the diffracted X-ray is fixed to twice the Bragg angle of 28.99&#xb0; of the {11-20} plane.

GaN substrate

Growing community of inventors

Ushiku, Japan

Masayuki Tashiro