Reduction of light induced degradation (LID) in B-doped Cz-Si solar cells by SiH4-free SiCxNy film

Boron doped Czochralski (Cz) silicon solar cells undergo efficiency degradation under illumination. The light induced degradation (LID) is related to the formation of B_s-O_2i complexes which act as a strong recombination centers. This paper shows that carbon present inside the SiC_xN_y films deposited from polymer solid or liquid source reduce the LID in boron doped Cz solar cells. The in situ grown carbon in the antireflection (AR) films provides a source of additional carbon which gets incorporated into the bulk silicon (Si) during the cell processing. This carbon competes with boron to form a carbon-oxygen related complex and reduces the B_s-O_2i concentration and the associated LID compared to conventional SiN_x coated solar cells. SiC_xN_y coated solar cells showed 0.1% loss in absolute efficiency due to LID relative to 0.3% degradation in the counterpart SiNx coated solar cells on 2 Ω-cm boron doped Cz material.