Structure and Photoelectric Properties of Sb-doped ZnTe Thin Films
ZOU Kai1,2, LI Rong-ping1,2, LIU Yong-sheng1,2, TIAN Lei1, FENG Song1
1. School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China;
2. Key Laboratory of Semiconductor Photovoltaic Technology at Universities of Inner Mongolia Autonomous Region, Hohhot 010021, China
Abstract:ZnTe and Sb-ZnTe polycrystalline thin films were prepared by vacuum evaporation on glass substrates and annealed in nitrogen environment. By using XRD, SEM, UV-VIS spectrophotometer and Hall effect measurements, the crystal structure, surface morphology, elemental composition, optical and electrical properties of the thin films were characterized, respectively, and the effects of Sb-doping amounts and heat treatment on the performance of the films were studied. The results show that pure ZnTe film is the cubic structure and preferentially orients in the (111) direction and its conductive type is P type. Sb-doping does not change the structure and conductive type of the films, but the intensity of diffraction peaks is lower than that of pure ZnTe films; the concentration of Sb directly affects the form of Sb in the ZnTe. Sb doping inhibits the combination of Te and Zn, and leads to the increase of Te in the films. In addition, the optical transmittance and optical band gap of the films depend on the concentration of Sb and annealing temperature, and Sb-doping can also result in an obvious increasing of carrier concentration and reduce the resistivity, which significantly enhance the conductivity of the films.
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