Regrowing characteristic of GaN on etched pits by MOCVD

GaN films etched in molten KOH are regrown for different hours. Scan electron microscope, X-ray diffraction, and photoluminescence are applied to study the regrowing characteristics of the GaN in etched pits and nearly. The GaN film regrown for 2 h has the lowest dislocation density and the best optical property. The slowly growing velocity in pits at early stage and the lateral growing at the edge of pits in late stage can restrain the propagation of pure screw threading dislocations. The asymmetrical regrowing characteristics on etch-pits will produce new edge threading dislocations and the connectivity of adjacent etch-pits can lessen edge threading dislocations.EI04415-4182