Interplay between segregation, roughness, and local strains in the growth of Ga0.75In0.25P alloy

In this work, using reflexion high energy electron diffraction and atomic force microscopy, we compare the growth of strained Ga0.75In0.25P alloys on GaAs(001) and GaP (001) substrates. We show that although the absolute strain value is similar in both cases, the transition from a bidimensional to a three-dimensional growth mode occurs much faster in the tensile case than in the compressive one. We interpret this result with a microscopic theoretical model which takes into account the interplay between a weak surface roughness, In vertical and lateral segregation, and strain effects.