Impurity incorporation and the surface morphology of MOVPE grown GaAs

The impact of impurity incorporation on the development of the surface morp hology of GaAs epilayers, grown by metalorganic vapor phase epitaxy (MOVPE) , has been systematically investigated. A variety of different doping eleme nts, including Mg, Zn, C, Si, O, and Se, were used to study the interaction between the impurity atoms and GaAs surface. Impurity atoms with smaller a tomic weight, belonging to group II and VI, have a larger influence on the surface morphology than the other dopants. Different chemical sources for c arbon doping were also used to explore the effect of surface growth chemist ry on the formation of surface features. The epilayer surface morphology wa s affected by the combination of several physical and chemical factors. Fac tors influencing the impact of an impurity on the growth front evolution ar e presented based on the interaction between the impurity atoms and the sur face step structures.