Thin films of magnesium phthalocyanine (MgPc) were coated on to glass substrates by thermal evaporation technique. The powder X-ray diffractogram indicated that MgPc crystallizes in monoclinic system with cell parameters 14.368 ÃÃ?â??Ã?â?¦, 4.898ÃÃ?â??Ã?â?¦, β = 119.860 with unit cell volume of 1153ÃÃ?â??Ã?â?¦ 3. The average volume occupied by a molecule is 288ÃÃ?â??Ã?â?¦3. The characteristic peak of phthalocyanine (MgPc) is found at 2θ = 7.84 with the hkl value of (100) for both MgPc powder and annealed thin film. The as deposited film was highly amorphous than the annealed film, because the presence of phthalocyanine crystallite form is observed in β-form. The surface morphology of the films annealed at 1500C for 1 hour showed more uniform sized grains than those prepared at room temperature. UV-Visible absorption spectra of pure MgPc thin film, annealed at different temperatures and time duration for annealing were studied. Linear increase in dark and photocurrent was observed for the films annealed at 1500 C for 1 hour. The variation of band gap energy with different annealing temperature for pure MgPc thin films were studied and the results are tabulated.
