Photoluminescence characterization of GaxIn1−xAs (0 ≤ x ≤ 0.32) strained quantum wells grown on InP by chemical beam epitaxy

We have investigated some characteristics of Ga_xIn_1−xAs/InP (x = 0, 0.2, 0.32) strained materials by growing multi-quantum wells with various well widths from 3 to 60 Å by chemical beam epitaxy. Growth conditions such as valve sequences and growth interruptions were optimised to have single-peaked photoluminescence spectra for all strained samples. Measured room temperature emission wavelengths were compared with theoretically estimated values. Photoluminescence linewidths were around 16 meV for most samples at 77 K, but broadened for well widths of less than 20 Å. Photoluminescence intensity also peaked at well width of 20 Å for all compositions. Performances of optical devices may be closely related to this “critical thickness” determined probably by the growth system limitation.