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 anti-surfactant 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 SiN 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.