ABSTRACT
We investigate interdiffusion in GaSb/AlxGa1-xSb heterostructures by means of bright-field transmission electron microscopy (TEM). Samples grown by metal organic molecular beam epitaxy (MOMBE) are subjected to thermal treatment under both Ga-rich and Sb-rich conditions. Concentration profiles of the group-III elements are determined by evaluating changes of thickness fringes of cleaved 90° wedge specimens on a nanometer scale. We present first results of our interdiffusion experiments and discuss these in view of the annealing conditions. We show that group-III vacancies play a dominant role in GaSb/AlSb interdiffusion and that the interdiffusion coefficient has a non-linear concentration dependency.
