A study of comparison of the electrical and optical characteristics of silicon solar cells (SC) with a layer of silicon oxide (SiO2) deposited by SILOX, and silicon solar cells covered with a silicon rich oxide (SRO) film obtained by LPCVD containing silicon nanoparticles (Si-nps) was made. To increase the density of nanoparticles and thus improve the red photoluminescence, the SRO films were annealed at 1100°C. Photoluminescence spectra and atomic force microscopy measurements of the silicon rich oxide films are presented and discussed, as well as current–voltage curves and spectral response of the fabricated solar cells. Measurement of the open circuit voltage and short circuit current of the SC under UV light illumination was realized. The results demonstrate that the red luminescence of these films with silicon nanoparticles, produces large enhancement of current and voltage, with improved performance in the UV range.