Monocrystalline silicon surface passivation by Al2O3/porous silicon combined treatment

In this paper, we report on the effect of Al2O3/porous silicon combined treatment on the surface passivation of monocrystalline silicon (c-Si). Al2O3 films with a thickness of 5, 20 and 80 nm are deposited by pulsed laser deposition (PLD). It was demonstrated that Al2O3 coating is a very interesting low temperature solution for surface passivation. The level of surface passivation is determined by techniques based on photoconductance and FTIR. As a result, the effective minority carrier lifetime increase from 2 μs to 7 μs at a minority carrier density (Δn) of 1 × 1015 cm−3 and the reflectivity reduce from 28% to about 7% after Al2O3/PS coating.