Penn, MichaelaMichaelaPennLuderer, ChristophChristophLudererReichel, ChristianChristianReichelGoldschmidt, Jan ChristophJan ChristophGoldschmidtFeldmann, FrankFrankFeldmannBivour, MartinMartinBivourHermle, MartinMartinHermle2023-05-312023-05-312022https://publica.fraunhofer.de/handle/publica/44235510.1063/5.00971822-s2.0-85137457125This work aims for providing a low-resistive passivating polycrystalline Si tunnel junction (poly-Si TJ) for interconnecting the sub cells in Perovskite/Si tandem solar cells. To account for the parasitic interdiffusion of dopant atoms during high-temperature processing, the incorporation of an additional diffusion blocking interlayer between the n+ and p+ poly-Si region of the tunnel junction is proposed. Several oxide-based interlayers have been investigated and are here discussed with respect to their deposition technique and structural properties. With the help of such interlayers, the design freedom for passivating poly-Si TJs is highly increased. The interlayers enhance the temperature stability of the layer stack and enable contact resistivities sufficiently low for tandem device application after high-temperature treatments of up to 900 or 950 °C. The developed front side poly-Si TJ is thereby compatible with the rear contact formation of the mainstream passivated emitter rear cell (PERC) technology.enconference paper