Manipulation of K center charge states in silicon nitride films to achieve excellent surface passivation for silicon solar cells

High quality surface passivation (S-eff < 5 cm/s) was achieved on polished float zone and textured p-and n-type solar grade Czochralski silicon substrates by externally injecting and storing positive or negative charges (> +/- 8 x 10(12) cm(-2)) into a dual layer stack of Plasma Enhanced Chemical Vapor Deposition (PECVD) Silicon Nitride (SiNx)/PECVD Silicon Oxide (SiO2) films using a corona charging tool. We demonstrate long term stability and uniform charge distribution in the SiNx film by manipulating the charge on K center defects while negating the requirement of a high temperature thermal oxide step. (C) 2014 AIP Publishing LLC.