Growth behavior and optical properties of V-pits in GaN grown by a Na flux method

Abstract

The presence of V-pit defects affects the growth and properties of GaN crystals. However, the growth behavior and properties of V-pit defects in Na flux method have not been investigated systematically. In this paper, the growth behavior and optical properties of V-pits of Na flux GaN was studied by cathodoluminescence. The growth of V-pits is related to the growth of the (101) planes in lateral growth and results in a higher incorporation of shallow donor impurities, thus leading to stronger near-band emission. With the (11m) planes' growth dominating, the V-pits gradually complete annihilation. The V-pit defects in GaN grown by a Na-flux method are observed by TEM to originate from mixed dislocations.