THE GROWTH AND PROPERTIES OF GROUP-III NITRIDES

We have studied a novel material system (AlGa)(AsN), which can be lattice matched to GaP (or more importantly Si), grown using a low temperature modified molecular beam epitaxy (MBE) technique to reduce the density of native defects. Active nitrogen is provided by an Oxford Applied Research, RF activated plasma source, This source has enabled us to prepare binary films of GaN and InN and alloy layers of Ga(AsN) and In(AsN) at growth rates of approximately 0.3 monolayers/s. The films have been studied using in-situ reflection high-energy electron diffraction (RHEED) and Anger electron spectroscopy (AES) and ex-situ using X-ray diffraction, C-V profiling and photoluminescence/excitation measurements. We have obtained clear evidence for the existence of films with significant concentrations of N (similar to 20%), using appropriate growth conditions.