Studies on high temperature vapor phase epitaxy of GaN

This paper deals with technological development and investigation of the high temperature vapor phase epitaxy (HTVPE) for the growth of GaN films. A novel Ga evaporation cell designed for an optimal local temperature field and gas flow is described. The influence of the reactor pressure and the temperature of the Ga melt on the growth rate in HTVPE is studied. The experiments demonstrated growth rates up to 165µm/h, which could be of potential interest for the deposition of thick GaN layers. Optical properties of the HTVPE layers, as well as typical process impurities are studied by PL, SIMS and GDMS, and discussed in detail. First experiments on a deposition of GaN films on sapphire substrates by HTVPE are presented.