Process for large-scale ammonothermal manufacturing of gallium nitride boules
AssigneeSLT Technologies, Inc.
InventorsMark P. D'Evelyn, Dirk Ehrentraut, Derrick S. Kamber, Bradley C. Downey
Life of this patent
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Abstract
Large-scale manufacturing of gallium nitride boules using m-plane or wedge-shaped seed crystals can be accomplished using ammonothermal growth methods. Large-area single crystal seed plates are suspended in a rack, placed in a large diameter autoclave or internally-heated high pressure apparatus along with ammonia and a mineralizer, and crystals are grown ammonothermally. The orientation of the m-plane or wedge-shaped seed crystals are chosen to provide efficient utilization of the seed plates and of the volume inside the autoclave or high pressure apparatus.
Claims23
A method for growth of a plurality of gallium-containing nitride crystals, the method comprising:
- placing a plurality of gallium-containing nitride seed plates in a seed rack, each of the plurality of gallium-containing nitride seed plates having a first growth surface and a second growth surface that are oriented relative to each other to form a wedge shape, wherein
- a wedge angle θ between the first growth surface and the second growth surface is between 1 degree and 60 degrees, and
- the first growth surface and the second growth surface have crystallographic orientations that are equivalent to one another to within 5 degrees;
- placing a source material, a mineralizer, and the seed rack that is supporting the plurality of gallium-containing nitride seed plates in a sealable container;
- introducing a nitrogen-containing solvent into the sealable container;
- and
- processing the plurality of gallium-containing nitride seed plates contained in the sealable container, wherein processing the plurality of gallium-containing nitride seed plates comprises growing a crystalline gallium-containing nitride material on the first growth surface and the second growth surface of each of the plurality of gallium-containing nitride seed plates by heating the plurality of gallium-containing nitride seed plates, the nitrogen-containing solvent, the gallium-containing source material, and the mineralizer disposed within the sealable container to a temperature higher than about 400 degrees Celsius.
A method for growing a gallium-containing nitride crystal, comprising:
- processing a plurality of gallium-containing nitride seed plates disposed within a sealable container, wherein
- a gallium-containing source material, a nitrogen-containing solvent, a mineralizer, and a seed rack are disposed within the sealable container, and the plurality of gallium-containing nitride seed plates are disposed on the seed rack,
- the plurality of gallium-containing nitride seed plates each have a first growth surface and a second growth surface, which is opposite to the first growth surface, and each have a crystallographic orientation that comprises a {1−1 0 0} plane crystallographic orientation that has a miscut angle towards a [000−1] direction of between 0.05 and 5 degrees and a miscut angle in a <11−20> direction less than or equal to 1 degree,
- the crystallographic orientations of at least two of the plurality of gallium-containing nitride seed plates differ from one another by at least 0.1 degree and less than 5 degrees towards the [000−1] direction, and
- wherein processing the plurality of gallium-containing nitride seed plates comprises heating the plurality of gallium-containing nitride seed plates, the nitrogen-containing solvent, the gallium-containing source material, and the mineralizer disposed with the sealable container to a temperature higher than 400 degrees Celsius.
Dependencies are inferred from the claim text.