Elimination of dislocations in heteroepitaxial layers by the controlled introduction of interfacial misfit dislocations

A procedure for the elimination of dislocations in layers of GaAlAsP on GaAs substrates has been developed and is described in this report. By carefully controlling the layer thickness and the lattice parameter mismatch at the growth temperature it is possible to change the direction of substrate dislocations as they enter the substrate/layer interface. The length of the dislocation in the interfacial plane can be extended such that it is ``infinitely'' long, i.e, it reaches the edge of the wafer.