Photoluminescence Due to Lattice-Mismatch Defects in High-Purity ZnSe Layers Grown by Metalorganic Vapor Phase Epitaxy

Abstract
High-purity ZnSe layers grown by metalorganic vapor phase epitaxy exhibit an unusually strong luminescence band at 2.60 eV (Y band), which is extremely sensitive to residual impurity concentration. Y emission depends on the lattice mismatch between the epilayer and substrate. The emission decreases with the use of a lattice-matched In x Ga1-x As substrate. With the GaAs substrate, the emission intensity varies with layer thickness reflecting lattice relaxation in the ZnSe/GaAs structure.