Study of recombination in CdMgTe/CdTeSe heterostructures using photoluminescence intensity and lifetime measurements with confocal photoluminescence microscopy

Abstract

Intensity-resolved and time-resolved PL are shown to be powerful tools for analyzing recombination in epitaxial CdTe appropriate for photovoltaic applications. Non-radiative defects such as dislocations are easily mapped and quantified by confocal photoluminescence. Very low dislocation density and twin content, as well as very high luminescence efficiency and measured lifetime (450 ns), can be achieved by Se-alloying to lattice match CdTeSe to InSb substrates. Analysis suggests the bulk lifetime for epitaxial CdTeSe is in excess of 700 ns.