HVPE growth of a ‐plane GaN on a GaN template (110)Si substrate

HVPE growth of a-plane (11-20)GaN was demonstrated. GaN growth was initiated from template GaN stripes, and each GaN stripes coalesced to get uniform crystal. At conventional growth temperature of 1000 °C, melt back etching was observed in GaN and surface morphology was poor. By lowering growth temperature to 870 °C, this phenomenon did not occur and morphology was also improved. NH3 flow rate was not effective on the morphology. RMS value was 0.78 nm to show the stability of the formation of surface. The dark spot density was as low as 107 cm-2. We found that most of dislocations were attributed to the coalescence of template stripes. CL spectrum showed the strong DBE peak. DAP emission and yellow luminescence were much weaker than DBE peak. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)