Low-Temperature Screen-Printed Metallization for the Scale-Up of Two-Terminal Perovskite–Silicon Tandems

Tandem photovoltaic devices based on perovskite and crystalline silicon (PK/c-Si) absorbers have the potential to push commercial silicon single junction devices beyond their current efficiency limit. However, their scale-up to industrially relevant sizes is largely limited by current fabrication methods which rely on evaporated metallization of the front contact instead of industry standard screen-printed silver grids. To tackle this challenge, we demonstrate how a low-temperature silver paste applied by a screen-printing process can be used for the front metal grid of two-terminal perovskite-silicon tandem structures. Small-area tandem devices with such printed front metallization show minimal thermal degradation when annealed up to 140 degrees C in air, resulting in silver bulk resistivity of <1 x 10(-5) Omega.cm. This printed metallization is then exploited in the fabrication of large area PK/c-Si tandems to achieve a steady-state efficiency of 22.6% over an aperture area of 57.4 cm(2) with a two-bus bar metallization pattern. This result demonstrates the potential of screen-printing metal contacts to enable the realization of large area PK/c-Si tandem devices.