GAS-SOURCE MOLECULAR-BEAM EPITAXY MIGRATION-ENHANCED EPITAXY GROWTH OF INAS ALSB SUPERLATTICES/

We report on the gas source molecular beam epitaxy/migration enhanced epitaxy (MEE) growth of InAs/AlSb superlattices. The incorporation beh avior of constituent group III and group V atoms during growth is inve stigated in detail using reflection high energy electron diffraction. In and Sb atoms are found to move towards the surface during MEE growt h, although the movement of In atoms can be reduced by lowering the gr owth temperature. Raman scattering measurement of InAs/AlSb superlatti ces shows that the formation of atomically controlled heterointerfaces (InSb- or AlAs-type interfaces in InAs/AlSb superlattices) is difficu lt. However, photoluminescence (PL) measurement shows that the optical properties of quantum well structures are strongly dependent on the s hutter sequence at the interfaces. 77 K PL from InAs/AlSb quantum well structures with an InSb-type interface shutter sequence is one order of magnitude stronger than that of the AlAs-type interface.