Study the Effect Thiourea Concentration to (Cu2S/Si) Heterojunction Photodetector by Chemical Bath Deposition (CBD)

The effect of the preparation conditions was studied by changing the molar concentration (M) for thiourea [CS(NH2)2] (0.6, 1, 1.3, 1.6 mol) On the Performance of (Cu2S/Si) photodetector which Prepared by (CBD) technique. The photovoltaic properties of the detector, which included the study of the characteristics of current-voltage in the case of darkness and using the forward bias and reverse bias at the rated voltages from -5 to +5V, The (Cu2S/Si) heterojunction is an asymmetric; the figure of merit (Ф) of the films was calculated as a function of molar concentration, The linear characteristics of the (Cu2S/Si) heterojunction were studied. The properties of the applied photodetector were studied, by The responsivity (Rλ) of all photodetectors which exhibits two peaks of response, the maximum responsivity was about 2.06A/W at 450nm and 2.13A/W at 850nm obtained for the photodetector prepared at 1.5mol. the Specific Detectivity (D*) showed two peaks in the Spectrum of the Specific Detectivity, Quantum Efficiency (η) was calculated and The minority carriers of the photodetector was measured, and the length of diffusion carriers was calculated.