The possibilities of electronic and opto-electronic device design using the Sb-containing alloys and heterostructures are largely unexplored. Part of the problem arises from the fact that some of these compounds exhibit miscibility gaps and spinodal decompositions in the phase diagrams. Molecular beam epitaxy is generally a far- from-equilibrium growth technique and, therefore, allows the low- temperature growth of these compounds within the miscibility gap. However, the materials can have severe alloy clustering and we, therefore, propose to study the growth of these alloys and heterostructures with in-situ and ex-situ characterization techniques. In particular, we will initiate our program with the growth of lattice-matched and strained GaSb, GaAlSb, and InAsSb, which will be extremely critical materials for a host of electronic and optical devices. Characterization of the layers will be done by temperature- dependent Hall, photoluminescence, absorption DLTS and Shubnikov-de Haas measurements. These should give a wealth of data regarding the fundamental materials characteristics. In addition, in-situ RHEED oscillations studies will be done to study the growth kinetics.
