GROUP III NITRIDE CRYSTAL SUBSTRATE, METHOD FOR PRODUCING SAME, AND GROUP III NITRIDE SEMICONDUCTOR DEVICE

摘要

A method for producing a group III nitride crystal substrate comprising a step for introducing an alkali metal element-containing substance (1), a group III element-containing substance (2) and a nitrogen element-containing substance (3) into a reaction container (51), a step for forming a melt (5) containing at least an alkali metal element, group III element and nitrogen element in the reaction container (51), and a step for growing a group III nitride crystal (6) from the melt (5) is characterized in that the alkali metal element-containing substance (1) is handled within a dry container (100) wherein the moisture concentration is controlled to 1.0 ppm or less at least during the step wherein the alkali metal element-containing substance (1) is introduced into the reaction container (51). Consequently, there can be obtained a group III nitride crystal substrate having a small light absorption coefficient. Also disclosed is a group III nitride semiconductor device. ® KIPO & WIPO 2007