Structure of CdZnTe films on glass

Polycrystalline Cd1−xZnxTe films were grown on glass substrates over the full range of compositions (0 < x < 1) by metal–organic chemical vapour deposition at 480 °C. The films (~5 µm thick) showed uniform texture oriented along the 1 1 1 direction, perpendicular to the substrate, independent of the film composition. The dependence of the lattice parameter of cubic Cd1−xZnxTe on the composition followed Vegard's law. The thick Cd1−xZnxTe films were shown to be of a single phase and structurally stable. The average grain size in the thick films was in the range 3–5 µm. The dominant imperfections in the films were twins (mostly Σ = 3) and dislocations. The x-ray diffraction (XRD) FWHM parameter reached a maximum at x = 0.5. Transmission electron microscopy (TEM) in situ heating in the range 200–400 °C caused plastic deformation in the grains without causing ordering effects. Optical absorption and low-temperature photoluminescence measurements confirmed the XRD and TEM results.