Impurity incorporation and the surface morphology of MOVPE grown GaAs
The impact of impurity incorporation on the development of the surface morphology of GaAs epilayers, grown by metalorganic vapor phase epitaxy (MOVPE), has been systematically investigated. A variety of different doping elements, 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 atomic weight, belonging to group II and VI, have a larger influence on the surface morphology than the other dopants. Different chemical sources for carbon doping were also used to explore the effect of surface growth chemistry on the formation of surface features. The epilayer surface morphology was affected by the combination of several physical and chemical factors. Factorsinfluencing the impact of an impurity on the growth front evolution are presented based on the interaction between the impurity atoms and the surface step structures.