Novel Nano-Pyramid/Polish Hybrid Morphology Designed for High-Efficiency Passivated Contact Solar Cells

Abstract

In photovoltaic applications, the rear surface morphology of tunnel oxide passivated contact (TOPCon) solar cells plays a critical role in their performance. However, traditional textured and polished surface morphologies both have limitations. This study introduces a hybrid nano-pyramid/polish morphology, combining a nano-pyramid structure on a polished surface. This new design aims to capitalize on the advantages of both textured and polished surfaces, achieving an optimal balance for TOPCon performance. The balance is achieved through an additional chemical solution treatment process. When applied to TOPCon solar cells, the hybrid structure outperforms both secondary-textured and polished morphologies in terms of optical absorption, passivation, and contact performance. The nano-pyramid/polish hybrid achieves a superior balance between light trapping, passivation, and contact quality. Furthermore, the study investigates the impact of rear surface morphology on film blistering, revealing that rougher surfaces are less prone to blistering. This is likely due to more favorable stress distribution in the SiO_x/poly-Si stack, enhancing mechanical stability. These findings demonstrate the compatibility of the hybrid nano-pyramid/polish morphology with TOPCon solar cells, offering a promising pathway to enhance efficiency. The insights gained may also benefit the development of other high-performance solar cell technologies, such as heterojunction (HJT) and silicon/perovskite tandem solar cells, advancing industrial photovoltaic applications.