Loss Analysis and Performance Optimization Pathways of 729-mV V_oc Si Solar Cells with Poly-Si on Locally-Etched Dielectric Passivating Contacts

In this article, the loss analysis of silicon solar cells with polysilicon on locally-etched dielectric passivating contacts with V-oc=729.0 mV and efficiency=22.6% has been presented. Experimentally, nano-pinholes were introduced in SiOx (2.2 nm) and SiOx/SiNy (2.2 nm/8nm) stack using metal-assisted chemical etching (MACE). SunSolve and Quokka3 were used to simulate the experimental solar cell and investigate the optical and electrical power losses. Simulations suggest maximum power loss occurs due to recombination and resistive losses in the bulk (similar to 0.76 mW/cm(2)) followed by power loss due to rear contact recombination (similar to 0.35 mW/cm(2)). Recombination at the front surface also contributes to 0.24 mW/cm(2). The effect of improving the bulk lifetime and lowering the recombination current density at the rear side on V-oc, FF and hence, efficiency has been investigated. Further, advanced structures have been proposed to minimize recombination and parasitic absorption to achieve higher V-oc and J(sc) of the solar cells with locally-etched dielectric passivating contacts.