Initial Stages of Interface Formation: The Influence of Surface Reconstruction

The initial stages of interface formation are crucial for the growth of an overlayer, particularly for ultra-thin films. While growth rate, growth temperature and lattice match are important parameters in molecular beam epitaxy, growth of semiconductor heterostructures always begins on a reconstructed surface. The effect of this reconstruction has to be known before a complete understanding of the growth process is possible. Two example will be discussed: (1) A necessary condition for perfect growth is the reordering of the substrate surface, i.e. those atoms at the interface which are originally displaced due to the reconstruction have to be brought back to bulk positions.