Mitsubishi Chemical Corporation

University of California

Japan Science and Technology Agency

Kenji Fujito

Satoru Nagao

Shuichi Kubo

Hirotaka Ikeda

Yutaka Mikawa

Hideo Fujisawa

Kazunori Kamada

Yusuke Tsukada

Tae Mochizuki

Yuuki Enatsu

Shuji Nakamura

Tadao Hashimoto

Kazumasa Kiyomi

Masayuki Tashiro

Hirotaka Oota

Tetsuharu Kajimoto

Yasuhiro Uchiyama

Takashi Fukada

Hajime Matsumoto

Kunitada Suzaki

Yoko Mashige

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 10.0×10Å or less is observed.

Self-standing GaN substrate, GaN crystal, method for producing GaN single crystal, and method for producing semiconductor device

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&#xd7;10&#x212b; or less is observed.

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 periodic table Group 13 metal nitride crystals grown with a non-polar or semi-polar principal surface have numerous stacking faults. The purpose of the present invention is to provide a period table Group 13 metal nitride crystal wherein the occurrence of stacking faults of this kind are suppressed. The present invention achieves the foregoing by a periodic table Group 13 metal nitride crystal being characterized in that, in a Qx direction intensity profile that includes a maximum intensity and is derived from an isointensity contour plot obtained by x-ray reciprocal lattice mapping of (100) plane of the periodic table Group 13 metal nitride crystal, a Qx width at 1/300th of peak intensity is 6&#xd7;10rlu or less.

Periodic table group 13 metal nitride crystals and method for manufacturing periodic table group 13 metal nitride crystals

A method of growing high-quality, group-III nitride, bulk single crystals. The group III-nitride bulk crystal is grown in an autoclave in supercritical ammonia using a source material or nutrient that is a group III-nitride polycrystals or group-III metal having a grain size of at least 10 microns or more and a seed crystal that is a group-III nitride single crystal. The group III-nitride polycrystals may be recycled from previous ammonothermal process after annealing in reducing gas at more then 600&#xb0; C. The autoclave may include an internal chamber that is filled with ammonia, wherein the ammonia is released from the internal chamber into the autoclave when the ammonia attains a supercritical state after the heating of the autoclave, such that convection of the supercritical ammonia transfers source materials and deposits the transferred source materials onto seed crystals, but undissolved particles of the source materials are prevented from being transferred and deposited on the seed crystals.

Method for growing group III-nitride crystals in supercritical ammonia using an autoclave

Provided is a high-quality Group III nitride crystal of excellent processability. A Group III nitride crystal is produced by forming a film is composed of an oxide, hydroxide and/or oxyhydroxide containing a Group III element by heat-treating a Group III nitride single crystal at 1000&#xb0; C. or above, and removing the film.

Group III nitride crystal production method and group III nitride crystal

Provided is a base substrate with which a Group-III nitride crystal having a large area and a large thickness can be grown while inhibiting crack generation. A single-crystal substrate for use in growing a Group-III nitride crystal thereon, which satisfies the following Z1&#x3e;0 expression (1), wherein Z1 (&#x3bc;m) is an amount of warpage of physical shape in a growth surface of the single-crystal substrate and Z2&#x3c;0 expression (2), wherein Z2 (&#x3bc;m) is an amount of warpage calculated from a radius of curvature of crystallographic-plane shape in a growth surface of the single-crystal substrate.

Process for producing a group-III nitride crystal and process for producing a light-emitting semiconductor element or a semiconductor device comprising a group-III nitride crystal

The method for producing a group III nitride semiconductor crystal comprises preparing a seed crystal having a non-polar plane followed by growing a group III nitride semiconductor from the non-polar plane in a vapor phase, wherein the growing includes growing the group III nitride semiconductor so as to extend in the +C-axis direction of the seed crystal. A group III-V nitride semiconductor crystal having high quality and a large-area non-polar plane can be obtained by the method.

Method for producing group-III nitride semiconductor crystal, group-III nitride semiconductor substrate, and semiconductor light emitting device

Provided is a base substrate with which a Group-III nitride crystal having a large area and a large thickness can be grown while inhibiting crack generation. A single-crystal substrate for use in growing a Group-III nitride crystal thereon, which satisfies the following expression (1), wherein Z1 (&#x3bc;m) is an amount of warpage of physical shape in a growth surface of the single-crystal substrate and Z2 (&#x3bc;m) is an amount of warpage calculated from a radius of curvature of crystallographic-plane shape in a growth surface of the single-crystal substrate: &#x2212;40&#x3c;Z2/Z1&#x3c;&#x2212;1: Expression (1).

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Ushiku, Japan

Kenji Fujito