Initial Stages of Molecular Beam Epitaxical Growth of Highly Strained Inxga1-XAs on Gaas (100)

We have studied the initial stages of highly mismatched InxGa1-x As growth on GaAs (100) by transmission electron microscopy (TEM). We find direct evidence of (i) deformation in the substrate below each island to depths of about 150 A and (ii) strain relief in the islands at their lateral edges. Growth morphology as a function of growth temperature is studied and it is found that the tendency for islanding for x as high as 0.5 can be supressed to a large extent by a reduction in the growth temperature. We also present results of correlation between TEM determined different growth morphologies (brought about by different growth temperatures ) and the electrical characteristics of AlAs/InxGa1-xAs resonant tunneling diode structures grown on GaAs (100).