Maximizing carrier extraction in hybrid back-contact silicon solar cells

"Hybrid back-contact (BC) silicon solar cells combine the strengths of TOPCon-derived n-type contacts, SHJ-derived p-type contacts, and interdigitated BC (IBC) device structures. Though high performance in the form of 27.8% efficiency has been demonstrated, the understanding of the fundamental advantages of the hybrid BC architecture over conventional BC cells (e.g. eliminating front-surface metallization shading) remains unexplored."

"We take advantage of the design flexibility of the hybrid BC architecture to use a multifunctional front layer for both light trapping and passivation. Meanwhile, we improved carrier collection and process compatibility of the rear carrier-selective contacts. We also show the optimal c-Si absorber thickness is increased to 160-m, leading to a certified efficiency of 27.62%."

Hybrid back-contact silicon solar cells combine advantages of TOPCon-derived n-type contacts, SHJ-derived p-type contacts, and interdigitated back-contact device structures. The research explores fundamental advantages of hybrid back-contact architecture over conventional back-contact cells, particularly eliminating front-surface metallization shading. A multifunctional front layer provides both light trapping and passivation capabilities. Carrier collection and process compatibility of rear carrier-selective contacts were enhanced. The optimal crystalline silicon absorber thickness was increased to 160 micrometers. These improvements resulted in a certified efficiency of 27.62% for industrially compatible crystalline silicon solar cells, demonstrating significant advancement in photovoltaic technology.

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