Abstract: Through Afors-Het simulation software,the TOPCon solar cell model is established and the effects of tunneling through the oxide SiO₂layer thickness,n⁺poly-Si layer doping concentration,back-metal electrode work function and energy band offset of the SiO₂n⁺poly-Si side on the performance of TOPCon solar cells are systematically analyzed.The simulation results show that the SiO₂/n⁺poly-S stacked passivation structure can achieve better electron selective transport performance.It is the best process window when the thickness of the SiO₂layer is 1.1 nm and the doping concentration of the n⁺poly-Si layer is 1×10²⁰cm^-3.It also shows the great potential of improving the electron selective transport layer for the efficiency improvement of TOPCon solar cells.