Interplay of impurity segregation and lattice mismatch in molecular beam epitaxy of III′–III″–V compounds plus dopant: application to the InGaAs:Sn nanoheterolayer growth

Abstract

A thermodynamic model for molecular beam epitaxy of quaternary solid alloys III′–III″–V plus dopant is developed on a practical example of In1x Gax As:Sn/GaAs heterolayer growth. In the frame of the model, the interplay of surface segregation and strain during epitaxy is analyzed. It is shown Sn atoms, being segregated during the growth in the In–stabilized conditions, act as an efficient surfactant, and Sn doping may be used to improve the surface morphology of strained nanoheterolayers. It is found that high doping level and the low growth temperatures are favourable for achieving a smooth morphology. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)