Optical Parameters of ZnO Thin Films

Zinc oxideZinc Oxide (ZnO) is a very important material with diverse uses in solar cells, optoelectronic devices, and other applications. Optimizing the optical properties is required in such applications. In this work the influence of annealing in nitrogen atmosphereAtmosphere and aluminum doping on the optical properties was investigated. Undoped (ZnO) and aluminum doped (ZnO:Al) thin films were deposited using spray pyrolysisSpray Pyrolysis (SP) method on glass substrates, and some of these films were annealed in nitrogen atmosphereAtmosphere. The microstructure of the films was explored using X-ray diffraction, and it is found that the films are polycrystalline. Transmittance of the films was recorded as a function of wavelength in the range of 300–1100 nm. Transmittance was used to calculate the absorption coefficient, extinction coefficient, reflectance, refractive index, real and imaginary parts of the dielectric constant, and optical conductivity. All these parameters are found to be affected by Al-doping and annealing. It is found that optical parameters were influenced by Al-doping and annealing.