Material and Si-based diode analyses of sputtered ZnTe thin films

Abstract

Structural, optical, and electrical properties ZnTe thin films grown by magnetron sputtering technique were studied by X-ray diffraction, atomic force microscopy, Raman spectroscopy, and electrical conductivity measurements. Structural analyses showed that ZnTe thin films grown on soda–lime glass substrates have a cubic crystalline structure. This crystalline nature of the films was also discussed in terms of Raman active modes. From atomic force microscopy images, the smooth and dense surface profile was observed. The conductivity of the film at room temperature was measured as 2.45 × 10−4 (Ω cm)−1 and the temperature dependency of conductivity showed Arrhenius behavior. The dark conductivity profile was modeled by thermionic emission mechanism and activation energies were extracted. In addition, the conductivity values indicated an increasing behavior with illumination intensity applied between 20 and 115 mW/cm2. The heterojunction diode was generated by sputtering ZnTe film on n-Si wafer substrate and the rectification behavior was evaluated to determine the main diode parameters.