Metallisation of Boron-Doped Polysilicon Layers by Screen Printed Silver Pastes

In this work, we report on hole selective passivating contacts, which consist of a SiOx tunnel layer and an in situ boron-doped 300nm thick p(+) polysilicon layer deposited by LPCVD. Using a SiNx:H capping layer, we show an extremely low dark saturation current density J(0) of 1fAcm(-2) after contact firing. At the same time, we demonstrate that commercially available and screen-printed fire through Ag pastes are capable of contacting the p(+) polysilicon layer, with minimum contact resistance (c)=2mcm(2). We do find increased interface recombination below the metal contacts of around 250fAcm(-2), which represents a considerable advance compared to conventional screen printed metallisation on diffused junctions.