Progress with surface passivation of heavily doped n+ silicon by industrial PECVD SiNx films

Significant progress in surface passivation of phosphorus diffused n ⁺ silicon surfaces is reported in this work using standard industrial inline plasma-enhanced chemical vapor deposited (PECVD) silicon nitride (SiN _x ) films deposited on ultrathin (~0.6 nm) chemically grown silicon oxide (SiO _x ). Record low emitter saturation current density (J _0e ) values of 10 and 22 fA/cm ² are reported for 170-Ω/sq planar and textured n ⁺ silicon, respectively. Contactless corona-voltage measurements revealed mid-gap interface defect density D _it at the Si surface to be about 1×10 ¹¹ eV ^-1 cm ^-2 for SiN _x films deposited on the ultrathin SiO _x . It is explained that the surface passivation mechanism of the fabricated samples to be completely ruled by chemical passivation.