The formation of nitridation damage during the growth of GaN on GaAs(001)

We report a correlation between the surface reconstruction transition durin g the initial phase of the molecular beam epitaxy growth of GaN on GaAs(001 ) and the nitridation damage determined final layer morphology. In order to study the formation of the nitrogen damage under a wide range of growth co nditions, a series of layers were grown by changing the V/III-ratio through the Ga-flux, while keeping all other growth parameters constant. The resul ts, describing the strong effect of the first N-terminated GaN (3 x 3) mono layer, were summarised in defect formation models for N-rich and Ga-rich co nditions, defining the means of near-stoichiometric growth.