The influence of Fe substitution into photovoltaic performance of p-CuO/n-Si heterojunctions

Fe-substituted CuO thin films have been prepared by spin coating onto cleaned n-Si and glass substrates at various concentrations (2%, 6%, 10%). The AFM results show that the surface morphology of CuO thin films is strongly influenced by film thickness. The optical band gaps of the films were determined with Kubelka Munk function by using diffuse reflectance data and a reduction of 59 meV in the optical band gap was observed for 10% Fe doped CuO film. The ideality factors and barrier height values of the diodes have been varied between 3.17 and 2.74 and 0.82 and 0.71 eV with the 2%, 6%, and 10% Fe doping, respectively. Additionally, the series resistance (RS) values have been defined via employing the Cheung-Cheung method. The highest and lowest values of RS have been calculated as 1332 ohm for CuO/n-Si and 18 ohm for 6%Fe:CuO/n-Si, respectively. The electrical characteristics of these heterojunction structures have been examined under dark and different illumination intensities. Moreover, their photovoltaic performances have been compared. Furthermore, the power conversion efficiencies of CuO:Fe/n-Si have been calculated and found to be increased from 0.1 to 1.13% with increasing Fe doping.

Automated summary

The research found that Fe-doped CuO thin films with different concentrations exhibit varying surface morphology and optical properties. The ideality factors and barrier height values of the diodes also change with different Fe doping levels. The electrical characteristics of these heterojunction structures vary under different illumination intensities.