US 2026/0234833 A1Published application

Beta-digallium trioxide single crystal substrate, method for manufacturing beta-digallium trioxide single crystal, and method for manufacturing beta-digallium trioxide single crystal substrate

AssigneeSumitomo Electric Industries, Ltd.

InventorsYoshiaki HAGI, Keisuke TANIZAKI, Yukio ISHIKAWA

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Abstract

A beta-digallium trioxide single crystal substrate has a circular main surface, and has a diameter of 100 mm or more. Second density/first density, which is a ratio between a first density that is a density of line-shaped holes in a first region having a diameter of a length of 0.75D centered at the center of the main surface, and a second density that is a density of line-shaped holes in a second region which is a region outside the first region on the main surface, is larger than 1.0. The second density is 1000 cm−2 or less. D represents a diameter of the substrate, and a unit of the D is mm. The line-shaped hole has a length of 10 μm or more and 200 μm or less, a width of 0.01 μm or more and 2 μm or less, and a depth of 0.1 μm or more.

Claims10

Dependent claims

A beta-digallium trioxide single crystal substrate comprising a circular main surface, wherein

the beta-digallium trioxide single crystal substrate has a diameter of 100 mm or more,
the main surface is a (001) plane of a beta-digallium trioxide single crystal constituting the beta-digallium trioxide single crystal substrate, or alternatively is a face having an off-angle of more than 0° and 10° or less from the (001) plane of the beta-digallium trioxide single crystal, and having an off-direction in a [010] direction of the beta-digallium trioxide single crystal or a direction orthogonal to the [010] direction,
second density/first density, which is a ratio between a first density that is a density of line-shaped holes in a circular first region having a diameter of a length of 0.75D centered at the center of the main surface, and a second density that is a density of line-shaped holes in a second region which is a region outside the first region on the main surface, is larger than 1.0,
the second density is 1000 cm−2 or less,
the D represents a diameter of the beta-digallium trioxide single crystal substrate, and a unit of the D is mm,
the line-shaped hole has a length of 10 μm or more and 200 μm or less, a width of 0.01 μm or more and 2 μm or less, and a depth of 0.1 μm or more, and
the density of the line-shaped holes in the first region and the density of the line-shaped holes in the second region are each the number of the line-shaped holes per 1 cm2, which is determined by forming a virtual grid in which squares each having a side of 10 mm are laid out so that the largest number of squares are arranged in parallel without overlapping with each other, on the main surface, and counting the number of the line-shaped holes present in each of the squares constituting the grid by using a differential interference microscope.

4 more elements

A method for manufacturing a beta-digallium trioxide single crystal with use of a vertical boat method, comprising:

preparing a single crystal growing apparatus comprising at least a cylindrical crucible and a heating apparatus that is arranged so as to surround an outer periphery of the crucible;
accommodating a seed crystal in a bottom portion of the crucible, and
accommodating a massive digallium trioxide bulk body in an upper portion above the seed crystal in the crucible;
heating the crucible with the heating apparatus to melt the digallium trioxide bulk body and a part of the seed crystal, thereby obtaining a digallium trioxide melt, and contacting the digallium trioxide melt with a remaining portion of the seed crystal;
and
obtaining the beta-digallium trioxide single crystal by growing a crystal on the remaining portion of the seed crystal from the digallium trioxide melt, wherein
the crucible is formed from a platinum-rhodium alloy, and
the obtaining of the beta-digallium trioxide single crystal comprises inserting a stirring rod formed from a platinum-rhodium alloy into the digallium trioxide melt and growing the crystal while stirring the digallium trioxide melt with the stirring rod.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 19/156,012Filed 15 Feb 2023
Published: 13 Aug 2026
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

C30B 29/16
Inorganic compounds or compositions: oxides
C30B 11/007
Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method: mechanisms for moving either…
C30B 11/02
Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method: without using solvents
C30B 19/067
Reaction chambers; Boats for supporting the melt; Substrate holders: boots or containers