METHOD FOR PRODUCING HEXAGONAL SINGLE CRYSTAL, METHOD FOR PRODUCING HEXAGONAL SINGLE CRYSTAL WAFER, HEXAGONAL SINGLE CRYSTAL WAFER, AND HEXAGONAL SINGLE CRYSTAL ELEMENT

摘要

In a process for growing a hexagonal single crystal, an off angle is imparted to a hexagonal single crystal, which serves as a base for the growth of the crystal, in a first direction [11-20] relative to a basal plane [0001] that serves as the main crystal growth plane, so that such a cross-sectional shape that the thickness of the crystal is gradually decreased in a step-like manner from a reference line AA' that is parallel to the first direction [11-20] toward second directions [-1100] and [1-100] that respectively extend toward the both sides of the reference line AA' and are perpendicular to the first direction [11-20] is formed in the hexagonal single crystal. In this manner, the dislocation that penetrates in the c-axis direction contained in the hexagonal single crystal can be converted into a defect that is inclined at 40˚or more in the basal plane direction against the c-axis direction during the growth of the crystal, and the direction of the propagation of the defect can be adjusted to a direction that is included between the opposite direction [-1-120] of the first direction [11-20] and the second directions [-1100] and [1-100], whereby the defect can be eliminated out of the crystal.