Growth of 4H-SiC on AlN/Si(100) complex substrate by chemical vapor deposition

Using chemical vapor deposition method, 4H-SiC films were grown on AlN/Si(100) complex substrates at the relatively low temperature (< 1100°C). The results show that there are Al and N present in the SiC film due to the thermal diffusion of Al and N from the substrate. Two photoluminescence peaks, being located at 3.01 eV and 3.17 eV respectively, have been observed at the room temperature. The lower energetic peak is related to Al acceptor and the higher energetic peak to N shallow donor. The ionization energy of Al acceptor level and N donor level is then obtained to be 0.21 eV and 0.06 eV, respectively. The photoluminescence peak located at 3.36 eV corresponds to the secondary conduction band of 4H-SiC at M point, and the gap between the lowest and the secondary conduction band is deduced as 0.125 eV.