Influence of deposition angle on nano-structure, optical and electrical properties of copper azide (CuN3) thin films

Cu/glass films of 100 (nm) thicknesses were deposited at 0 degrees and 40 degrees and post annealed at three different temperatures with flow of nitrogen. XRD patterns of the films deposited at 40 degrees confirmed formation of CuN3 phase which is due to higher void fraction in these films. Optical properties of the produced samples were obtained using the Bruggeman homogenization method. Results of optical properties of these films showed that the dispersion behavior is sensitive to the annealing temperature, polarization of the incident light and film deposition angle. Clear energy loss peak is obtained for film deposited at 0 degrees and annealed at 350 degrees C using both s- and p-polarized incident lights with a shift to lower energies for p-polarized incident light. Appearance of these peaks are related to the values of the dielectric functions and the structure of the sample which consists of almost evenly distributed conical shapes with sharp tips leading to the enhancement of plasmon resonances and the corresponding frequency in this sample. The surface morphology of the produced samples was analyzed by means of field emission electron microscope and atomic force microscope. Variation of grain size with annealing temperature is observed which can be due to competition between two processes of diffusion and penetration of nitrogen atoms/molecules in the body of the grains.