GROWTH AND OPTICAL CHARACTERIZATION OF STRAINED CDZNTE/CDTE QUANTUM-WELLS

We have grown strained Cd(1-x)Zn(x)Te (x almost-equal-to 0.2)/CdTe single and multiple quantum wells by molecular beam epitaxy. GaAs was used as a substrate. The well widths were systematically increased until the critical thickness was exceeded. Low-temperature (liquid helium) photoluminescence (PL) spectroscopy was used to characterize the films. Two prominent PL peaks were observed: one arising from the quantum well and the other from the barrier matarial. The energy of the quantum well luminescence is consistent with theory when strain is included. The critical layer thickness for the CdTe quantum wells was found to be between 150 and 175 angstrom, in agreement with the model of Matthews and Blakeslee.