Influence of the discharge mode on the optical and passivation properties of SiNx:H deposited by PECVD at atmospheric pressure

Abstract : The cost of industrial silicon solar cells could be greatly reduced by the implementation of PECVD at atmospheric pressure for the deposition of the silicon nitride (SiN) antireflective coating. For a successful development of this vacuum-free process tool, a deep understanding of the plasma discharge mode has to be undertaken. This work focuses on the control of a wide range of plasma excitation conditions in order to obtain homogeneous dielectric barrier discharges (DBD) at atmospheric pressure, and thus dense and uniform SiN layers. The influence of the discharge mode is then studied in order to optimize the optical and passivation properties of the SiN thin films, showing good antireflective properties as well as surface recombination velocities as low as 15 cm.s-1.