A NEW APPROACH TO PREPARE POLYCRYSTALLINE PbTe-TeO THIN FILM, AND ITS OPTICAL, STRUCTURAL, SURFACE AND ELECTRICAL CHARACTERIZATION

In this study, PbTe thin film was produced on glass substrates, via chemical bath deposition (CBD) method, with 3-h deposition time at 50(circle)C. The produced thin film had polycrystalline structure; TeO2, PbTe, PbTe3 and Te2O5 crystals that were characterized by X-ray diffraction (XRD) had tetragonal, cubic, tetragonal and monoclinic crystal structures, respectively. Reflectivity (R; in %), optical transmission (T; in %), optical bandgap (Eg), absorption, dielectric constant (epsilon), extinction coefficient (k) and refractive index (nr) of polycrystalline PbTe thin film obtained using UV-Vis spectrophotometer were 29.87%, 19.41%, 3.30eV, 0.6, 3.72, 0.05 and 4.08, respectively. Grain sizes of polycrystalline PbTe thin film varied between 8.79nm and 52.55nm. Optical and electrical conductivities of the crystals according to photon energy were calculated using optical parameters, whereas their surface morphology was characterized by scanning electron microscopy (SEM). The thickness of polycrystalline PbTe thin film was measured by atomic force microscopy (AFM), and found to be 900nm.

Automated summary

A PbTe thin film was successfully deposited on glass substrates using the CBD method, exhibiting a polycrystalline structure with various crystal phases. The optical and electrical properties, as well as the morphology of the film, were characterized through XRD, UV-Vis spectrophotometer, SEM, and AFM.