Numerical Modeling and Design Optimization of Industrial Tunnel Oxide Passivated Contact Solar Cells with Selective Passivated Contacts on the Front

The exceptional passivation of TOPCon on the rear of Si solar cells has motivated researchers to explore its application on the front side. However, having a full-area front poly-Si passivated layer may lead to high absorption loss, subsequently reducing photo-generated current density (Jgen) and overall efficiency. To address this issue, the implementation of a selective poly-Si layer on the front has been proposed, aiming to increase Jgen and efficiency. It is generally recognized that narrower selective poly-Si widths contribute to decreased parasitic absorption losses, thus resulting in enhanced efficiency. However, identifying the optimal poly-Si width—one that strikes a balance between maximum benefits and the feasibility of industrial mass-production—necessitates further in-depth research. This study investigates the benefits of front selective (localized) TOPCon in industrial bifacial passivated contacts (biPC) solar cells, employing Sentaurus TCAD for optical ray tracing and electrical simulations to analyze the effects of varying selective poly-Si widths and thickness on the efficiency of industrial biPC solar cells. Our simulations project a potential efficiency of approximately 25.2%, guided by optimal parameters from literature and the industrial standards reported in ITRPV 2023.