Preparation and characterization of CuInSe2 electrodeposited thin films annealed in vacuum

From the evolution of the full width at half maximum (FWHM) of the (1 1 2) peak, we have estimated the grain size versus the annealing temperature. The results show that the grain size increases from 0.45 to 0.75 μm with the annealing temperature. The morphological, optical and electrical properties of the CIS films have been investigated respectively, by the scanning electron microscopy (SEM), UV-vis spectroscopy and I-V characteristics. The band gaps of the CIS films also shows an evolution when the temperature is varied. In fact the band gap decreases from 1.24 eV at 250 °C to 0.98 eV at 450 °C. The electrical characterization of the junction Al/CIS/FTO shows an interesting Schottky rectifying behavior.