Progress in surface passivation of heavily doped n-type and p-type silicon by plasma-deposited AlO x/SiNx dielectric stacks

Abstract

We report an outstanding level of surface passivation for both n + and p+ silicon by AlO x/SiNx dielectric stacks deposited in an inline plasma-enhanced chemical vapor deposition (PECVD) reactor for a wide range of sheet resistances. Extremely low emitter saturation current densities (J-{0e}) of 12 and 200 fA/cm2 are obtained on 165 and 25 Ω/sq n+ emitters, respectively, and 8 and 45 fA/cm2 on 170 and 30 Ω/sq p + emitters, respectively. Using contactless corona-voltage measurements and device simulations, we demonstrate that the surface passivation mechanism on both n+ and p+ silicon is primarily due to a relatively low interface defect density of