Patent ID: 7227172
Filing Date: 2007-06-05
Classification: H01L,Y10S,Y10T

Abstract:
1. A Group-III-element nitride semiconductor device, comprising: a Group-III-element nitride crystal substrate; a Group-III-element nitride crystal layer stacked on the Group-III-element nitride crystal substrate; and a thin film layer, wherein the Group-III-element nitride crystal substrate is produced by allowing nitrogen of nitrogen-containing gas and a Group III element to react with each other to crystallize in a melt containing at least one of alkali metal and alkaline-earth metal, the Group-III-element nitride crystal substrate includes a threading dislocation, at least one of alkali metal and alkaline-earth metal is present as impurities in a region where the threading dislocation is present, the thin film layer is formed on the Group-III-element nitride crystal substrate and has a lower diffusion coefficient than that of the Group-III-element nitride crystal substrate with respect to impurities contained in the Group-III-element nitride crystal substrate, and wherein the impurities are at least one of Na and Li.