INFLUENCE OF ANNEALING TEMPERATURE ON THE STRUCTURAL AND OPTICAL PROPERTIES OF COPPER IODIDE THIN FILMS
Copper Iodide (CuI) nanoparticles with (250 nm) thickness have been prepared at RT on glass substrate using PLD technique with focused Nd:YAG laser beam at (800 mJ) with a frequency second radiation at (1064 nm) (pulse width 9 ns) repetition frequency (6 Hz), for 500 laser pulses incident on the target surface . The films annealed to different annealing temperatures (423K )and(523K). The structural and surface morphology properties of the deposited CuI thin films were examined by X-ray diffraction analysis (XRD) and Atomic force microscope (AFM). The X-ray diffraction show that structure is a cubic phase with (111) plane preferential orientation direction. AFM was used to examine and measure the morphology and average diameter for CuI thin films respectively. It is observed that the average nanoparticles size increases with increasing of annealing temperature. The optical measurements showed that CuI thin films have direct allowed energy gap transition and the energy gap (Eg) decreases from (3.2eV) to (2.8 eV) with increasing annealing temperatures from RT to (532 K) for all samples.
Keywords: Copper Iodide, Optical Properties ,PLD Technique ,Annealing