Effect of bath concentration on the growth and photovoltaic response of SILAR-deposited CuO thin films

Solar cell property of p-CuO/n-Si heterojunction was investigated using SILAR-deposited CuO thin films. The effects of copper salt concentration on the growth of CuO films and its effect on the efficiency in solar cell conversion were investigated. Structural, morphological, optical and electrical studies of the CuO thin films deposited at 90 A degrees C with different copper sulphate concentrations are reported. Crystallinity of the film is found to increase with the increase in copper sulphate concentration. The measured Raman spectrum of the deposited film showed peaks corresponding to CuO phase. It is observed by the SEM that the film is homogeneous fully covering the substrate. The optical band gap of the deposited film has exhibited a decrease in band gap from 1.76 to 1.57 eV with the increase in copper sulphate concentration. Solar cell device was constructed using the p-CuO film deposited on n-silicon substrate, and its photovoltaic response was measured. It showed increasing photoresponse with increasing concentration of copper sulphate.