Combined effect of strained-layer superlattice and annealing in defects reduction in GaAs grown on Si substrates

Abstract
The high defect density in GaAs grown on Si can be reduced by the combined use of the strained superlattices (InGaAs-GaAsP) and annealing. The strained-layer superlattice (SLS) bends the dislocations and acts as a medium for dislocations interactions, and annihilations. Highly strained SLS (∼2%) is required to bend the dislocations and keep them bent at the SLS interfaces. The SLS coupled with annealing permits a remarkable reduction of threading dislocation density. Annealing provides the energy for threading dislocations to interact with the SLSs and improves their efficiency significantly.