GROUP ? NITRIDE CRYSTAL SUBSTRATE, METHOD OF ITS MANUFACTURE, AND GROUP-? NITRIDE SEMICONDUCTOR DEVICE

摘要

Affords a Group-III nitride crystal substrate that is of low dislocation density and is inexpensive to manufacture, a method of manufacturing such a substrate, and Group-III nitride semiconductor devices that incorporate the Group-III nitride crystal substrate. The Group-III nitride crystal substrate manufacturing method includes: a step of growing, by liquid-phase epitaxy, a first Group-III nitride crystal (2) onto a base substrate (1); and a step of growing, by vapor-phase epitaxy, a second Group-III nitride crystal (3) onto the first Group-III nitride crystal (2). The Group-III nitride crystal substrate, produced by such a manufacturing method, has a dislocation density of 1 × 10 7 dislocations/cm 2 .