Cathodoluminescence study of laser recrystallized CdTe layers

Abstract

CdTe(100)/GaAs(100) and CdTe(lll)/CdTe(lll) layers grown by metalorganic vapor phase epitaxy (MOVPE) were investigated The layers were recrystallized to improve their morphology by scanning the surface with a 100 mu m diameter spot from an Ar ion laser beam (lambda=514.4 nm). Cathodoluminescence spectra from both as-grown and recrystallized CdTe MOVPE layers are used to monitor the effect of the recrystallization procedure. The laser recrystallization results in important changes on the spectral distribution of luminescence. Deep-level bands associated to different defects are shown to be very sensitive to the laser recrystallization procedure. The effect of the different substrates on the defect structure of the layers is also related to the changes observed in the cathodoluminescence spectra.