| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for growing a gallium nitride crystal by which a gallium nitride substrate having high quality can be produced. SOLUTION: (1) A striped mask M is provided on a ground substrate. (2) The growth of a gallium nitride crystal is started from an exposed part where no mask exists and facets F are formed on both sides of the mask. (3) When a polarity reversal region J where c-axis is reversed by 180°is formed, rugged projections called as a pawl Q are generated oppositely in the middle of the inclined face of each facet as an indication. (4) Thereafter, the pawls Q are unified, and (5) a crystal having the same orientation grows in the vertical direction by using the unified pawl Q as a seed, and a crystal defect aggregation region H composed of a polarity reversal crystal J is formed. Although a portion grown on the exposed part and below the facet has at first many dislocations between the ground substrate and itself, the dislocation density in the portion is gradually reduced because the dislocations are eliminated to outside by the growth of the facet and accumulated in the crystal defect aggregation region H, and the portion adjacent to the region H becomes a single crystal. COPYRIGHT: (C)2008,JPO&INPIT
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