DISLOCATION PATTERNING - A NEW TOOL FOR SPATIAL MANIPULATION OF GE ISLANDS

The ability of dislocation patterns to control the lateral distributio n of islands on the surface of strained heteroepitaxial systems is elu cidated. We have studied the behaviour of Ge deposited on a Si surface modified by misfit dislocations generated in buried compositionally g raded Si1-xGex layers. A pronounced ordering of the Ge islands on the dislocation-structured substrates is revealed, It is shown that this s triking phenomenon is caused by the inhomogeneous surface-strain patte rns associated with the misfit dislocations. The results open a new pa thway to spatial manipulation of zero-dimensional structures in hetero epitaxial semiconductor systems.