Anti-surfactant in III-nitride epitaxy - Quantum dot formation and dislocation termination

A new approach toward epitaxial growth of group III nitrides using an "anti-surfactant" is presented. Two unique phenomena, quantum dot formation and dislocation termination, were recognized using this approach. The presence of Si atoms as an antisurfactant on (Al)GaN surfaces modified the nitride epitaxial growth kinetics. These phenomena appeared to be independent; however, the growth mechanisms indicated a common surface event, which included the formation of a monolayer thick Si-N mask (nano-mask) within the fractional coverage on the surface. The Si-N nano-mask influenced the morphology of the deposited GaN surface, i.e. quantum structures, and also contributed to the termination of threading dislocations in GaN films.