SUMMARY ABSTRACTDespite the 4.2% lattice mismatch, several laboratories have demonstrated that the quality of GaAs grown on Si is high enough for practical device applications [1–5]. At the GaAs/Si interface, a dislocation density of roughly 1012cm−2 is required to accommodate the mismatch. Therefore various techniques of dislocation filtering are necessary to provide material with acceptable dislocation counts. Among these techniques are the use of tilted substrates, strained layer superlattices, and intermediate layers.
