Morphological and Optical Properties of Dimetallo-Phthalocyanine-Complex Thin Films

In this work, the synthesis of semiconducting molecular materials formed from metallo-phthalocyanines (MPcs) and bidentate amines is reported. Powder and thin-film samples of the synthesized materials, deposited by vacuum thermal evaporation, show the same intra-molecular bonds in IR-spectroscopy studies. The morphology of the deposited films was studied using scanning electron microscopy and atomic force microscopy. The optical parameters have been investigated using spectrophotometric measurements of transmittance in the wavelength range 200 - 1100 nm. The absorption spectra in the UV-Vis region for the deposited samples showed two bands, namely the Q and Soret bands. The optical band gap values of the thin films were calculated from the absorption coefficient alpha in the absorption region and were found to be around 1.4 - 1.6 eV. The dependence of the Tauc and Cody optical gaps on the thickness of the film was also determined.