Structural and optical properties of nanocrystalline aluminum phthalocyanine chloride thin films

Thin films of aluminum phthalocyanine chloride (AlPcCl) were fabricated, with different thicknesses (109–518 nm) using thermal evaporation technique. Structural and optical properties of AlPcCl thin films were investigated. The material in powder form showed a polycrystalline nature with monoclinic structure. Miller indices, hkl, values for each diffraction line in X-ray diffraction (XRD) spectrum were calculated. The field emission scanning electron microscope (FESEM) showed the nanostructure property of the as-deposited thin films. The optical properties of the thin films were studied by the spectrophotometric measurements of the transmittance, T, and the reflectance, R, at the normal incidence of the light in the spectral range 200–2500 nm. The refractive and absorption indices of the thin films were calculated and were found to be independent of film thickness of 109–518 nm. The films exhibited indirect allowed inter-band transitions. The optical band gaps transitions were calculated as 1.42, 2.87 and 3.69 eV, respectively. Also, different dispersion and absorption parameters were determined for thin films of AlPcCl.