Abstract: A device (1) for generating high pressures in solid and liquid media is described. The device (1) includes a lower shell-shaped body half (2) and an upper shell-shaped body half (3). The device (1) further includes a lower elastic membrane (6) and an upper elastic membrane (7), which are each inserted into the lower body half (2) and into the upper body half (3), respectively. The respective body half (2, 3) and the respective membrane (6, 7) inserted into it each surround a pressure chamber (62, 73). The device (1) furthermore includes an opening and a channel (14) in the lower body half (2), in order to attach an oil line from an oil pump to the device and to pump the oil into the pressure chamber between the lower body half (2) and the elastic membrane (6) inserted into it. The pressure chambers (62, 73) in the lower body half (2) and in the upper body half (3) communicate by means of a line.

Abstract: A process for making gallium nitride crystals comprising the steps of charging a reaction vessel with a layer of one selected from a Group IA element nitride, a Group IIA element nitride, and combinations thereof, adding a layer of gallium, applying nitrogen pressure to prevent dissociation or decomposition, forming in situ a gallium nitride source by heating the charged reaction vessel to render the one selected from the group reacted with the gallium, forming in situ a solvent comprising the gallium and the one selected from the group released by an exchange reaction between the gallium and the one selected from the group, providing a temperature when formed gallium nitride will be dissolved in the formed solvent and providing a temperature difference in the solvent between the formed gallium nitride source and the growing single crystal gallium nitride, and growing a single crystal gallium nitride.

Abstract: In one embodiment, this invention pertains to a process for making single crystal gallium nitride in the region of the phase diagram of gallium nitride where gallium nitride is thermodynamically stable.