Time-resolved photoluminescence of ZnS/sub x/Se/sub 1-x/(0</spl times/<0.12) epilayers on GaAs grown by MBE

Abstract

Abstracts.We have reported steady-state and time-resolved PL studies of ZnS,Sel, epilayers grown on GaAs substrate by molecular beam epitaxy with various sulfur compositions around the lattice matching composition (0 < x < 0.12). We have investigated the PL decay dynamics of ZnS,Sel, epilayers, and found that the decay time of the ZnS,Se,, epilayer with sulfur composition closely lattice-matched with the substrate is longer than that of any other lattice-mismatched one. This is interpreted as indicatig that the crystalline defects induced by lattice mismatch with the substrate mainly act as nonradiative recombination centers and consequently reduce the PL lifetimes of the epilayers. These studies suggest that the lattice mismatch has a strong correlation with PL lifetimes of the ZnS,Sel, epilayers.