ROLE OF SURFACE-ENERGY AND SURFACE RECONSTRUCTIONS ON THE 2D-TO-3D GROWTH-MODE TRANSITION OF STRAINED INXGA1-XAS LAYERS ON INP(001)

We show that the role played by surface energy in the total-energy bal ance between the initial two-dimensional (2D) state and the final thre e-dimensional (3D) state is of prime importance to explain morphologie s observed during the molecular-beam epitaxy growth of strained materi als. This was established by analyzing differences in 2D-3D transition onsets for 2% mismatched InxGa1-xAs films grown on InP(001) substrate s when changing the mismatch sign (compression or tension), the film d oping, and the type of surface stabilization (anion or cation). The 2D -3D onsets were measured by reflection high-energy electron diffractio n and the corresponding surface morphologies characterized by scanning tunneling microscopy.