Morphology, structural and optical characterization of electron beam evaporated bromoaluminium phthalocyanine (BrAlPc) thin films

Bromoaluminium phthalocyanine (BrAlPc) thin films have been deposited onto pre-cleaned glass substrates by electron beam evaporation technique. Thin films have been characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and optical absorption (UV-Vis) spectra. XRD studies of BrAlPc thin film deposited at room temperature shows the indication of the alpha-phase. FESEM images have shown that the most of particles are spherical in shape with an average size about 26-34 nm. Using UV-Visible spectra over the wavelength range 300-800 nm, the optical band gap, absorption coefficient and extinction coefficient of BrAlPc thin films are evaluated. The optical absorption measurements of thin films show that the absorption mechanism is due to direct transition.