Published online by Cambridge University Press: 14 September 2005
GaN is grown on Si-face 4H-SiC(0001) substrates using remote plasma-assisted metalorganic chemical vapour deposition (RP-MOCVD). The pre-dissociation of nitrogen by the remote plasma is used for lowering the deposition temperature to approximately 700 °C. Remote plasma processing is also used for SiC surface pre-treatments including a low-temperature atomic hydrogen cleaning (by remote H2 plasma) and nitridation (by remote N2 plasma). Furthermore, in situ spectroscopic ellipsometry is used for monitoring in real time all the steps of substrate pre-treatments and the heteroepitaxial growth of GaN on SiC. Our characterization emphasis is on understanding the nucleation mechanism and the GaN growth mode, which depend on the SiC surface preparation.