Abstract: Methods for quantifying extended defects in a gallium-containing nitride crystal, wafer, or device, are disclosed. The methods include providing a gallium-containing nitride crystal, wafer, or device, processing the gallium-containing nitride crystal, wafer, or device in an etchant solution comprising one or more of H3PO4, H3PO4 that has been conditioned by prolonged heat treatment to form polyphosphoric acid, and H2SO4; removing the gallium-containing nitride crystal, wafer, or device from the etchant solution; and quantifying the concentration of at least one of etch pits or etch grooves.

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.

Abstract: A scintillator material is made of a zinc-oxide single crystal grown on a +C surface or a ?C surface of a plate-shaped seed crystal of zinc oxide including a C surface as a main surface. The zinc-oxide single crystal contains In and Li. In response to an incident radiation, the scintillator material emits fluorescence of less than 20-ps fluorescence lifetime.

Abstract: High quality ammonothermal group III metal nitride crystals having a pattern of locally-approximately-linear arrays of threading dislocations, methods of manufacturing high quality ammonothermal group III metal nitride crystals, and methods of using such crystals are disclosed. The crystals are useful for seed bulk crystal growth and as substrates for light emitting diodes, laser diodes, transistors, photodetectors, solar cells, and for photoelectrochemical water splitting for hydrogen generation devices.

Abstract: Methods for large-scale manufacturing of semipolar gallium nitride boules are disclosed. The disclosed methods comprise suspending large-area single crystal seed plates in a rack, placing the rack in a large diameter autoclave or internally-heated high pressure apparatus along with ammonia and a mineralizer, and growing crystals ammonothermally. A bi-faceted growth morphology may be maintained to facilitate fabrication of large area semipolar wafers without growing thick boules.

Abstract: A scintillator material is made of a zinc-oxide single crystal grown on a +C surface or a ?C surface of a plate-shaped seed crystal of zinc oxide including a C surface as a main surface. The zinc-oxide single crystal contains In and Li. In response to an incident radiation, the scintillator material emits fluorescence of less than 20-ps fluorescence lifetime.

Abstract: A method for producing a nitride semiconductor, comprising controlling temperature and pressure in a autoclave containing a seed having a hexagonal crystal structure, a nitrogen element-containing solvent, a raw material substance containing a metal element of Group 13 of the Periodic Table, and a mineralizer so as to put said solvent into a supercritical state and/or a subcritical state and thereby ammonothermally grow a nitride semiconductor crystal on the surface of said seed, wherein the crystal growth rate in the m-axis direction on said seed is 1.5 times or more the crystal growth rate in the c-axis direction on said seed. By the method, a nitride semiconductor having a large-diameter C plane or a nitride semiconductor thick in the m-axis direction can be efficiently and simply produced.