Low Pressure CVD of GaN from GaCl3 and NH3

ABSTRACTWe report on the heteroepitaxial growth of GaN from GaCl3 and NH3 on (0001) A12O3 and (0001) 6H-SiC substrates. In order to enable homogeneous growth within the entire deposition zone one has to use low process pressures in the 10-1 mbar range, where still a growth rate of ∼ 2 μm/h can be achieved. We present a simple model to describe our process and explain our observations. A comparison of GaN deposited on different substrates and with GaN buffer layers is given by low temperature Photoluminescence (PL). Furthermore, impurities are traced by secondary ion mass spectroscopy (SIMS).