Effects of annealing on the morphology and optical property of copper (II) phthalocyanine nanostructured thin films

Copper (II) phthalocyanine (CuPc) thin films deposited at room temperature on indium tin oxide (ITO) substrates have exhibited a change in their surface morphology with the post-deposition annealing temperature under normal atmosphere. These films have been characterized by optical absorption, X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM). The FESEM images have shown densely packed nanoparticle- and nanorod-like structures for the substrates annealed at different temperatures. The fractal dimension of the assembly of nanostructures in the films has been estimated from FESEM images. The effect of annealing temperature on the surface morphology, optical properties and the fractal dimension has been discussed.