OPTICAL AND PHOTOVOLTAIC PROPERTIES OF CuSe THIN FILMS

Copper selenide thin films have been deposited by spraying a mixture of aqueous solutions (0.50 M) of copper chloride hydrate (CuCl2·2H2O) and selenourea (H2NC (Se) NH2) at various substrate temperatures. The as deposited copper selenide thin films were used to study a wide range of characteristics including structural, surface morphological, optical, electrical, and photovoltaic power output characteristics. X-ray diffraction (XRD) study reveals that the films are polycrystalline in nature with hexagonal (mineral klockmannite) crystal structure. The SEM study reveals that the grains are uniform with uneven spherically shaped and spread over the entire surface of the substrates. The direct band gap values are found to be in the range 2.29-2.36 eV depending on the substrate temperature. The measured values of efficiency (η) and fill factor (FF) are found to be 0.99 % and 0.51 respectively for film deposited at 350oC.