Patent ID: 7964890

Claim:
A III-V-semiconductor-containing epitaxial substrate comprising: a wafer substrate comprising gallium arsenide; a sacrificial layer comprising at least one of Ge, GaAsN, GaAsSb and InGaAs, applied to the wafer substrate, and having a band gap smaller than the band gap of the wafer substrate; an epitaxial layer structure configured to emit radiation and applied to the sacrificial layer opposite to the wafer substrate; a first etch-stop layer between the wafer substrate and the sacrificial layer; a second etch-stop layer between the sacrificial layer and the epitaxial layer structure; a first lattice-match layer between the first etch-stop layer and the sacrificial layer; and a second lattice-match layer between the sacrificial layer and the second etch-stop layer, such that said lattice-match layers eliminate or reduce the occurrence of lattice defects in the epitaxial layer structure.