A Review on p-Type Tunnel Oxide Passivated Contact (TOPCon) Solar Cell

The primary objectives of solar cell technology are high efficiency, long durability, mass manufacturing, cost effectiveness, and the use of environmentally benign components. Among high-efficiency crystalline silicon (c-Si)-based solar cell types, tunnel oxide passivated contact (TOPCon) solar cells have attracted particular attention because of a multitude of advantages. These include easy processing, high efficiency potential, and availability of raw materials. Due to cheaper wafer pricing, easily compatible with advanced and long-tested PERC solar cell manufacturing process, fabrication of TOPCon solar cells starting with p-type c-Si wafers are significantly more demanding from the standpoint of mass production of solar module. If cutting-edge high-efficiency technologies were used in industrial production, the quality of the p-type wafer may eventually become a bottleneck. Recent production lines elsewhere have developed p-type TOPCon solar cells with 25.19% conversion efficiency using monocrystalline Czochralski (CZ) c-Si wafers. This effectively proves the outstanding viability of p-type TOPCon solar cells for an industrial scale. This review article comprehensively discusses the history of high-efficiency p-type TOPCon solar cells, advancement in various areas to increase effective cell performance, state of commercialization, as well as potential future research opportunities and challenges.