Sumitomo Electric Industries, Limited

Takuji Okahisa

Kensaku Motoki

Seiji Nakahata

Ryu Hirota

Koji Uematsu

Naoki Matsumoto

Hideaki Nakahata

Michimasa Miyanaga

Hitoshi Kasai

Naho Mizuhara

Keisuke Tanizaki

Yoshiyuki Yamamoto

Yoshiki Nishibayashi

Shinsuke Fujiwara

Natsuo Tatsumi

Tomoki Uemura

Fumitaka Sato

Kouji Uematsu

Hideyuki Ijiri

Shunsuke Fujita

Akinori Koukitu

Takashi Sakurada

Yoshiki Miura

Mitsuru Shimazu

Hisashi Seki

Masato Matsushima

Muneyuki Nishioka

Katsushi Akita

Makoto Kiyama

Tomohiro Kawase

Shin Hashimoto

Tatsuya Nishimoto

Satoshi Arakawa

Manabu Okui

A method of manufacturing a diamond substrate includes: forming an ion implantation layer at a side of a main surface of a diamond seed substrate by implanting ions into the main surface of the diamond seed substrate; producing a diamond structure by growing a diamond growth layer by a vapor phase synthesis method on the main surface of the diamond seed substrate, after implanting the ions; and performing heat treatment on the diamond structure. The performed heat treatment causes the diamond structure to be separated along the ion implantation layer into a first structure including the diamond seed substrate and failing to include the diamond growth layer, and a diamond substrate including the diamond growth layer. Thus, the method of manufacturing a diamond substrate is provided that enables a diamond substrate with a large area to be manufactured in a short time and at a low cost.

Method of manufacturing diamond substrate, diamond substrate, and diamond composite substrate

A GaN-crystal free-standing substrate obtained from a GaN crystal grown by HVPE with a (0001) plane serving as a crystal growth plane and at least one plane of a {10-11} plane and a {11-22} plane serving as a crystal growth plane that constitutes a facet crystal region, except for the side surface of the crystal, wherein the (0001)-plane-growth crystal region has a carbon concentration of 5&#xd7;10atoms/cmor less, a silicon concentration of 5&#xd7;10atoms/cmor more and 2&#xd7;10atoms/cmor less, and an oxygen concentration of 1&#xd7;10atoms/cmor less; and the facet crystal region has a carbon concentration of 3&#xd7;10atoms/cmor less, a silicon concentration of 5&#xd7;10atoms/cmor less, and an oxygen concentration of 5&#xd7;10atoms/cmor more and 5&#xd7;10atoms/cmor less.

GaN-crystal free-standing substrate and method for producing the same

Group-III nitride crystal composites made up of especially processed crystal slices, cut from III-nitride bulk crystal, whose major surfaces are of {1-10&#xb1;2}, {11-2&#xb1;2}, {20-2&#xb1;1} or {22-4&#xb1;1} orientation, disposed adjoining each other sideways with the major-surface side of each slice facing up, and III-nitride crystal epitaxially present on the major surfaces of the adjoining slices, with the III-nitride crystal containing, as principal impurities, either silicon atoms or oxygen atoms. With x-ray diffraction FWHMs being measured along an axis defined by a &#x3c;0001&#x3e; direction of the substrate projected onto either of the major surfaces, FWHM peak regions are present at intervals of 3 to 5 mm width. Also, with threading dislocation density being measured along a &#x3c;0001&#x3e; direction of the III-nitride crystal substrate, threading-dislocation-density peak regions are present at the 3 to 5 mm intervals.

Composite of III-nitride crystal on laterally stacked substrates

Group-III nitride crystal composites made up of especially processed crystal slices, cut from III-nitride bulk crystal, whose major surfaces are of {1-10&#xb1;2}, {11-2&#xb1;2}, {20-2&#xb1;1} or {22-4&#xb1;1} orientation, disposed adjoining each other sideways with the major-surface side of each slice facing up, and III-nitride crystal epitaxially present on the major surfaces of the adjoining slices, with the III-nitride crystal containing, as principal impurities, either silicon atoms or oxygen atoms.

Affords Group-III nitride single-crystal ingots and III-nitride single-crystal substrates manufactured utilizing the ingots, as well as methods of manufacturing III-nitride single-crystal ingots and methods of manufacturing III-nitride single-crystal substrates, wherein the incidence of cracking during length-extending growth is reduced. Characterized by including a step of etching the edge surface of a base substrate, and a step of epitaxially growing onto the base substrate hexagonal-system III-nitride monocrystal having crystallographic planes on its side surfaces. In order to reduce occurrences of cracking during length-extending growth of the ingot, depositing-out of polycrystal and out-of-plane oriented crystal onto the periphery of the monocrystal must be controlled. A layer of the base substrate edge surface, as just described, where it has been mechanically altered is removed beforehand by etching, whereby crystallographic planes form on the side surfaces of the III-nitride single-crystal ingot that is formed onto the base substrate, which therefore controls depositing-out of polycrystal and out-of-plane oriented crystal and reduces occurrences of cracking.

III-nitride single-crystal ingot, III-nitride single-crystal substrate, method of manufacturing III-nitride single-crystal ingot, and method of manufacturing III-nitride single-crystal substrate

Provided is a method of manufacturing III-nitride crystal having a major surface of plane orientation other than {0001}, designated by choice, the III-nitride crystal manufacturing method including: a step of slicing III-nitride bulk crystal through a plurality of planes defining a predetermined slice thickness in the direction of the designated plane orientation, to produce a plurality of III-nitride crystal substrates having a major surface of the designated plane orientation; a step of disposing the substrates adjoining each other sideways in a manner such that the major surfaces of the substrates parallel each other and such that any difference in slice thickness between two adjoining III-nitride crystal substrates is not greater than 0.1 mm; and a step of growing III-nitride crystal onto the major surfaces of the substrates.

Method of manufacturing III-nitride crystal

A group III nitride semiconductor crystal substrate has a diameter of at least 25 mm and not more than 160 mm. The resistivity of the group III nitride semiconductor crystal substrate is at least 1&#xd7;10&#x3a9;&#xb7;cm and not more than 0.1 &#x3a9;&#xb7;cm. The resistivity distribution in the diameter direction of the group III nitride semiconductor crystal is at least &#x2212;30% and not more than 30%. The resistivity distribution in the thickness direction of the group III nitride semiconductor crystal is at least &#x2212;16% and not more than 16%.

Group III nitride semiconductor crystal substrate and semiconductor device

The invention relates to a GaN-crystal free-standing substrate obtained from a GaN crystal grown by HVPE with a (0001) plane serving as a crystal growth plane and at least one plane of a {10-11} plane and a {11-22} plane serving as a crystal growth plane that constitutes a facet crystal region, except for the side surface of the crystal, wherein the (0001)-plane-growth crystal region has a carbon concentration of 5&#xd7;10atoms/cmor less, a silicon concentration of 5&#xd7;10atoms/cmor more and 2&#xd7;10atoms/cmor less, and an oxygen concentration of 1&#xd7;10atoms/cmor less; and the facet crystal region has a carbon concentration of 3&#xd7;10atoms/cmor less, a silicon concentration of 5&#xd7;10atoms/cmor less, and an oxygen concentration of 5&#xd7;10atoms/cmor more and 5&#xd7;10atoms/cmor less.

A method of manufacturing a group III nitride semiconductor substrate includes the growth step of epitaxially growing a first group III nitride semiconductor layer on an underlying substrate, and the process step of forming a first group III nitride semiconductor substrate by cutting and/or surface-polishing the first group III nitride semiconductor layer. In the growth step, at least one element selected from the group consisting of C, Mg, Fe, Be, Zn, V, and Sb is added as an impurity element by at least 1&#xd7;10cmto the first group III nitride semiconductor layer. A group III nitride semiconductor substrate having controlled resistivity and low dislocation density and a manufacturing method thereof can thus be provided.

Group III nitride semiconductor substrate and manufacturing method thereof

A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided.

Fabrication method and fabrication apparatus of group III nitride crystal substance

III-nitride crystal composites are made up of especially processed crystal slices cut from III-nitride bulk crystal having, ordinarily, a {0001} major surface and disposed adjoining each other sideways, and of III-nitride crystal epitaxially on the bulk-crystal slices. The slices are arranged in such a way that their major surfaces parallel each other, but are not necessarily flush with each other, and so that the [0001] directions in the slices are oriented in the same way.

Group-III nitride crystal composite

The present III-nitride crystal manufacturing method, a method of manufacturing a III-nitride crystal () having a major surface () of plane orientation other than {0001}, designated by choice, includes: a step of slicing III-nitride bulk crystal () into a plurality of III-nitride crystal substrates (), () having major surfaces (), () of the designated plane orientation; a step of disposing the substrates (), () adjoining each other sideways in such a way that the major surfaces (), (qm) of the substrates (), () parallel each other and so that the [0001] directions in the substrates (), () are oriented in the same way; and a step of growing III-nitride crystal () onto the major surfaces (), () of the substrates (), ().

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Itami, Japan

Takuji Okahisa