Deep level photoluminescence commonly present in undoped Czochralski grown GaAs

Publisher Website
Google Scholar
Abstract
Photoluminescence (PL) under the below band-gap excitation with the 1.32-μm line of a yttrium aluminum garnet laser has been measured for undoped, semi-insulating Czochralski grown GaAs crystals. A Gaussian band with a peak at 0.67 eV and a half-width of 120 meV has been found to appear commonly, regardless of the groups of crystals classified according to their dominant PL band measured under the above band-gap excitation. The occurrence of the PL fatigue effect, the positive correlation of the PL intensity with the dislocation density, and the spectral shape indicate that the main deep donor EL2 is involved in the transition responsible for the 0.67-eV band.