First-principles simulation and experimental evidence for improvement of transmittance in ZnO films

ZnO/Ag/Glass films were prepared by a DC magnetron sputtering system, which exhibit both excellent properties of high conductivity and high transparency. Moreover, an enhancement of transmission of ZnO films was observed after brought into contact to a silver layer, but the understanding of experimental findings for the enhancement of transmission was insufficient. Therefore, the first-principles simulations of electrical and optical properties were utilized using the density functional theory with local-density approximations or generalized-gradient approximations. The crystal structure of ZnO or Ag was imported from the Material Studio database. The periodic supercell has the same atomic ratio with the experimental structure and was optimized using the CASTEP package in Material Studio. According to the calculation results, the enhancement in transmission is attributed to the surface plasmon polariton in the asymmetric structure films.