EFFECT OF AS-I ON THE OPTICAL-PROPERTIES OF GA1-XINXAS INP GROWN BY MOLECULAR-BEAM EPITAXY/

This report focuses on the effect of the As species and the V/III rati o on the optical properties of Ga1-xInxAs/LnP grown by molecular beam epitaxy (MBE). The band gap energies of the layers were measured by lo w temperature photoluminescence (PL) while the indium contents x were determined by X-ray for samples in the investigated range of 0.50 < x < 0.56. For the analysis of these data we considered the model of Kuo et al. which we confined with a correction for the different measureme nt temperatures in PL (4.2 K) and X-ray (300 K). Using As, with an eff ective V/III ratio higher than 1.3, we find the best agreement of the band gap energies and predictions of the theory. A lower V/III ratio a lways implies a reduction of the band gap energy to values 5-15 meV lo wer than expected. In contrast, using As-2 the PL data fit quite well independent of the effective V/III ratio above unity.