Patent ID: 7582498

Claim:
A method for producing a resonant cavity light emitting device, the method comprising: arranging a seed gallium nitride crystal and a source material in a nitrogen-containing superheated fluid in a container disposed in a multiple-zone furnace, the nitrogen-containing superheated fluid providing a medium for mass transport of gallium nitride precursors between the seed gallium nitride crystal and the source material, wherein the seed gallium nitride crystal has a dislocation density below 10 5 cm −2 and is substantially free of tilt boundaries, preparing a surface of the seed gallium nitride crystal, comprising applying a first thermal profile between the seed gallium nitride crystal and the source material while the seed gallium nitride crystal and the source material are arranged in the nitrogen-containing superheated fluid, wherein the first thermal profile includes a first temperature gradient between the seed gallium nitride crystal and the source material; growing gallium nitride material on the prepared surface of the seed gallium nitride crystal, the growing comprising applying a second thermal profile having a second temperature gradient that is different from the first temperature gradient between the seed gallium nitride crystal and the source material while the seed gallium nitride crystal and the source material are arranged in the nitrogen-containing superheated fluid, said growing producing a single-crystal gallium nitride substrate; and depositing a stack of group III-nitride layers on the single-crystal gallium nitride substrate, the stack comprising a first mirror sub-stack and an active region adaptable for fabrication into one or more resonant cavity light emitting devices.