Sumitomo Electric Industries, Limited

Other

Ryu Hirota

Seiji Nakahata

Koji Uematsu

Kensaku Motoki

Takuji Okahisa

Fumitaka Sato

Makoto Kiyama

Kouji Uematsu

Naoki Matsumoto

Hideaki Nakahata

Fumio Kawamura

Shinsuke Fujiwara

Masashi Yoshimura

Takatomo Sasaki

Yusuke Mori

Hitoshi Kasai

Hideyuki Ijiri

Shunsuke Fujita

Masaki Ueno

Tomohiro Kawase

Masami Tatsumi

Hiroaki Yoshida

Manabu Okui

Haruko Tanaka

A gallium nitride substrate has a surface with a diameter of not less than 100 mm, a difference being not less than 0.1 cmand not more than 2 cmbetween maximum and minimum values of wave numbers at a maximum peak of peaks corresponding to an Ephonon mode in micro-Raman scattering mapping measurement at each of square regions having sides each having a length of 2 mm, the square regions being located at a total of five locations including a central location and four circumferential edge locations on the surface of the gallium nitride substrate, a difference being not more than 2 cmbetween maximum and minimum values of the wave numbers at the maximum peak of the peaks corresponding to the Ephonon mode at all of measurement points in the five locations.

Gallium nitride substrate

There is provided a gallium nitride substrate having a C plane as a surface with a diameter of not less than 100 mm, the gallium nitride substrate including first regions and second regions having different average values of band-edge emission intensities in a micro photoluminescence mapping at 25&#xb0; C. in a square region located in the C plane and having sides each having a length of 2 mm, an average value Ibe1a of the band-edge emission intensities of the first regions and an average value Ibe2a of the band-edge emission intensities of the second regions satisfying the following relational expressions (I) and (II): Ibe1a&#x3e;Ibe2a . . . (I) and 2.1&#x2264;Ibe1a/Ibe2a&#x2264;9.4 . . . (II).

There is provided a gallium nitride substrate having a C plane as a surface with a diameter of not less than 100 mm, the gallium nitride substrate including first regions and second regions having different average values of band-edge emission intensities in a micro photoluminescence mapping at 25&#xb0; C. in a square region located in the C plane and having sides each having a length of 2 mm, an average value Ibe1a of the band-edge emission intensities of the first regions and an average value Ibe2a of the band-edge emission intensities of the second regions satisfying the following relational expressions (I) and (II):12&#x2003;&#x2003;(I)and2.1&#x2264;12&#x2264;9.4&#x2003;&#x2003;(II).

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

Affords methods of manufacturing bulk III-nitride crystals whereby at least the surface dislocation density is low globally. The present III-nitride crystal manufacturing method includes: a step of preparing an undersubstrate () containing a III-nitride seed crystal, the III-nitride seed crystal having a matrix (), and inversion domains () in which the polarity in the &#x3c;0001&#x3e; directions is inverted with respect to the matrix (); and a step of growing a III-nitride crystal () onto the matrix () and inversion domains (it) of the undersubstrate () by a liquid-phase technique; and is characterized in that a first region (), being where the growth rate of III-nitride crystal () growing onto the matrix () is greater, covers second regions (), being where the growth rate of III-nitride crystal () growing onto the inversion domains () is lesser.

III-nitride crystal substrate and III-nitride semiconductor device

Favorable-quality III-V crystals are easily obtained at low cost without causing cracks, even when using a variety of substrates, and can be used to manufacture semiconductor devices with good quality and at high yields. The III-V crystals are characterized by the following properties: the carrier concentration, resistivity, and dislocation density of the III-V compound crystal are uniform to within &#xb1;30% variation along the surface; the III-V compound crystal is misoriented from the c-plane such that the crystal surface does not include any region where its off-axis angle with the c-plane is 0&#xb0;; and the full width at half-maximum in XRD at the crystal center of the III-V compound is not greater than 150 arcsec.

III-V compound crystal and semiconductor electronic circuit element

Seeds are implanted in a regular pattern upon an undersubstrate. An AlInGaN (0&#x2266;x&#x2266;1, 0&#x2266;y&#x2266;1, 0&#x3c;x+y&#x2266;1) mixture crystal is grown on the seed implanted undersubstrate by a facet growth method. The facet growth makes facet pits above the seeds. The facets assemble dislocations to the pit bottoms from neighboring regions and make closed defect accumulating regions (H) under the facet bottoms. The closed defect accumulating regions (H) arrest dislocations permanently. Release of dislocations, radial planar defect assemblies and linear defect assemblies are forbidden. The surrounding accompanying low dislocation single crystal regions (Z) and extra low dislocation single crystal regions (Y) are low dislocation density single crystals.

[object Object]

A method of manufacturing a group III-nitride crystal substrate including the steps of introducing an alkali-metal-element-containing substance, a group III-element-containing substance and a nitrogen-element-containing substance into a reactor, forming a melt containing at least the alkali metal element, the group III-element and the nitrogen element in the reactor, and growing group III-nitride crystal from the melt, and characterized by handling the alkali-metal-element-containing substance in a drying container in which moisture concentration is controlled to at most 1.0 ppm at least in the step of introducing the alkali-metal-element-containing substance into the reactor is provided. A group III-nitride crystal substrate attaining a small absorption coefficient and the method of manufacturing the same, as well as a group III-nitride semiconductor device can thus be provided.

Group III-nitride crystal, manufacturing method thereof, group III-nitride crystal substrate and semiconductor device

Affords a Group-III nitride crystal substrate that is of low dislocation density and is inexpensive to manufacture, a method of manufacturing such a substrate, and Group-III nitride semiconductor devices that incorporate the Group-III nitride crystal substrate. The Group-III nitride crystal substrate manufacturing method includes: a step of growing, by liquid-phase epitaxy, a first Group-III nitride crystal () onto a base substrate (); and a step of growing, by vapor-phase epitaxy, a second Group-III nitride crystal () onto the first Group-III nitride crystal (). The Group-III nitride crystal substrate, produced by such a manufacturing method, has a dislocation density of 1&#xd7;10dislocations/cm.

Group III nitride crystal substrate, method of its manufacture, and group III nitride semiconductor device

Affords methods of manufacturing bulk III-nitride crystals whereby at least the surface dislocation density is low globally. The present III-nitride crystal manufacturing method includes: a step of preparing an undersubstrate () containing a III-nitride seed crystal, the III-nitride seed crystal having a matrix (), and inversion domains () in which the polarity in the &#x3c;0001&#x3e; directions is inverted with respect to the matrix (); and a step of growing a III-nitride crystal () onto the matrix () and inversion domains () of the undersubstrate () by a liquid-phase technique; and is characterized in that a first region (), being where the growth rate of III-nitride crystal () growing onto the matrix () is greater, covers second regions (), being where the growth rate of III-nitride crystal () growing onto the inversion domains () is lesser.

III-nitride crystal manufacturing method, III-nitride crystal substrate, and III-nitride semiconductor device

A method of manufacturing group III-nitride semiconductor crystal includes the steps of accommodating an alloy containing at least a group III-metal element and an alkali metal element in a reactor, introducing a nitrogen-containing substance in the reactor, dissolving the nitrogen-containing substance in an alloy melt in which the alloy has been melted, and growing group III-nitride semiconductor crystal is provided. The group III-nitride semiconductor crystal attaining a small absorption coefficient and an efficient method of manufacturing the same, as well as a group III-nitride semiconductor device attaining high light emission intensity can thus be provided.

Group III-nitride semiconductor crystal and manufacturing method thereof, and group III-nitride semiconductor device

Affords group III nitride crystal growth methods enabling crystal to be grown in bulk by a liquid-phase technique. One such method of growing group III nitride crystal from solution is provided with: a step of preparing a substrate having a principal face and including at least on its principal-face side a group III nitride seed crystal having the same chemical composition as the group III nitride crystal, and whose average density of threading dislocations along the principal face being 5&#xd7;10cmor less; and a step of bringing into contact with the principal face of the substrate a solution in which a nitrogen-containing gas is dissolved into a group III metal-containing solvent, to grow group III nitride crystal onto the principal face.

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Itami, Japan

Ryu Hirota