Charge trapping and storage in SiN x thin films deposited with Oxford PlasmaLab 100 system

Abstract

Negative charges in silicon nitride films are beneficial for surface passivation of rear side of p type solar cells.[1] Previous studies indicates that N-rich SiNx films in an oxide-nitride-oxide structure display good charge trapping and storage ability. In this work, an Oxford PlasmaLab 100 PECVD system is used to vary the deposition conditions (temperature and RF power). SiNx films deposited at 400°C and RF=60W show an initial negative charge density of 1.2×1013/cm2 after negative charge injection. Modeling results suggest that tunnel oxide may not be necessary for achieving good charge stability, which will make the application more flexible. Show more