X-Ray Radiation Sensing Properties of ZnS Thin Film: A Study on the Effect of Annealing
M. P. Sarma1, J. M. Kalita1,2**, G. Wary1
1Department of Physics, Cotton College, Guwahati 781001, India 2Department of Physics and Electronics, Rhodes University, Grahamstown 6140, South Africa
Abstract：Chemically synthesized ZnS thin film is found to be a good x-ray radiation sensor. We report the effect of annealing on the x-ray radiation detection sensitivity of a ZnS thin film synthesized by a chemical bath deposition technique. The chemically synthesized ZnS films are annealed at 333, 363 and 393 K for 1 h. Structural analyses show that the lattice defects in the films decrease with annealing. Further, the band gap is also found to decrease from 3.38 to 3.21 eV after annealing at 393 K. Current-voltage characteristics of the films are studied under dark and x-ray irradiation conditions. Due to the decrease of lattice defects and band gap, the conductivity under dark conditions is found to increase from $2.06\times10^{-6}$ to $1.69\times10^{-5}$ S/cm, while that under x-ray irradiation increases from $4.13\times10^{-5}$ to $5.28\times10^{-5}$ S/cm. On the other hand, the x-ray radiation detection sensitivity of the films is found to decrease with annealing. This decrease of detection sensitivity is attributed to the decrease of the band gap as well as some structural and surface morphological changes occurring after annealing.
. [J]. 中国物理快报, 2017, 34(7): 77802-.
M. P. Sarma, J. M. Kalita, G. Wary. X-Ray Radiation Sensing Properties of ZnS Thin Film: A Study on the Effect of Annealing. Chin. Phys. Lett., 2017, 34(7): 77802-.
2017, Vol. 34 
