Effects of adding an SiO2 film to the rear metal/semiconductor interface on the performance of a conventional solar cell based on n+p silicon

The modification of the rear surface of solar cells permits the considerable improvement of performance of these devices and solar cells with high yield. We have developed a numerical 1 D simulation code allowing study of the influence of the addition of an SiO₂ film between the back surface field (BSF) and the rear metallic contact. The code allows equal analysis of the contributions of different regions in the solar cell. We have established the division of the main results obtained that show that the thickness of the SiO₂ film plays a fundamental role in the determination of the performance of the solar cell. Another important result is obtained, justifying the use of the BSF to reduce the loss of yield and the open circuit voltage. At the end of this study, a performance optimisation of solar cells and the function of the length of the BSF, level of BSF doping, speed of rear surface recombination and thickness of the SiO₂ film is made