Photoluminescence caused by presence of defects and oxides at the surface of Hg/sub 1-x/Cd/sub x/Te

Abstract

The results of photoluminescence (PL) measurements performed for Hg/sub 1-x/Cd/sub x/Te (x=0.165) samples are presented. The surfaces of these samples were modified using long exposure to the atmosphere (series A), etching by 0.5% Br-methanol during 1 minute (series B) and during 5 minutes (series C). For each series samples PL spectra were measured at different temperatures in the range from 16 to 300 K. PL bands at about 2.1 eV and 2.3 eV are recognized in PL spectra of each series samples. The analysis of PL and Raman spectra shows that the band at /spl sim/2.1 eV is caused by presence of the nonstoichiometric oxides. The band at 2.3 eV originates of organic compounds which are deposited at the surface during etching process. PL of the observed samples decreases after irradiation by intense nanosecond pulse of Nd:YAG laser.