Passivation of crystalline silicon using silicon nitride

The extraordinary capacity of plasma-enhanced chemical-vapour-deposited (PECVD) silicon nitride (SiN) to passivate tire surface of crystalline silicon wafers and, in the case of multicrystalline silicon, improve the bulk material by hydrogenation has attracted a great deal of research and development. This review summarizes the state of the art of surface passivation by PECVD SiN, together with the present understanding of the physical mechanisms that underlie it. The impact of SiN on ultimate solar cell performance is discussed and an optimization of SiN passivated n(+) emitters is presented. Finally, the experimental evidence of SiN-induced hydrogenation of mc-Si is discussed and areas for further work are suggested.