Effective lifetime of minority carriers in black silicon nano-textured by cones and pyramids

Abstract

We calculated the dependence of the effective minority-carrier lifetime in black-silicon nano-textured with cones and pyramids on the diameter of the cone base, the side of the pyramid base, and the height of the cone and pyramid. The numerical calculation shows that the n-type polished plate of single-crystal silicon and the n-type plate of black silicon have a high minority-carrier lifetime in both the bulk and on the silicon surface, indicating high purity of both the bulk and the surface. However, the measured experimentally effective lifetime of minority carriers in the n-type black silicon is 1.55 ms and is determined by the surface lifetime. The measured effective lifetime of minority charge carriers in the p-type polished silicon is 1.24 ms. The minority carrier lifetime in the bulk of the polished p-type silicon is lower than the surface one.