INVESTIGATION OF CO-ETCHING PROCESS OF BORON-RICH AND PHOSPHORUS-RICH LAYERS FOR CRYSTALLINE SILICON SOLAR CELLS

Li Wenhao; Wang Huipeng; He Ren; Huang Zhiping; Wei Deyuan; Xu Ying

doi:10.19912/j.0254-0096.tynxb.2025-0626

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Acta Energiae Solaris Sinica ›› 2026, Vol. 47 ›› Issue (8) : 217-224. DOI: 10.19912/j.0254-0096.tynxb.2025-0626

INVESTIGATION OF CO-ETCHING PROCESS OF BORON-RICH AND PHOSPHORUS-RICH LAYERS FOR CRYSTALLINE SILICON SOLAR CELLS

Li Wenhao¹, Wang Huipeng¹, He Ren¹, Huang Zhiping², Wei Deyuan³, Xu Ying¹

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Abstract

The wet etching method with a mixed solution of nitric acid, hydrofluoric acid and deionized water is employed for the first time to achieve the co-etching of the boron-and phosphorus-rich layers on the 165 mm×165 mm substrate of crystalline silicon solar cell after thermal diffusion. The optimal co-etching conditions are determined as a mixed acid volume ratio of HF∶HNO₃∶H₂O=1∶5∶20 and the etching time of 5 min. The co-etching also simultaneously regulates the sheet resistance of the front emitter and the back collector junctions, reduces the surface defect density, and improves the performance of crystalline silicon solar cells.

Key words

solar cells / diffusion / wet etching / boron-rich layer / phosphorus-rich layer

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Li Wenhao, Wang Huipeng, He Ren, Huang Zhiping, Wei Deyuan, Xu Ying. INVESTIGATION OF CO-ETCHING PROCESS OF BORON-RICH AND PHOSPHORUS-RICH LAYERS FOR CRYSTALLINE SILICON SOLAR CELLS[J]. Acta Energiae Solaris Sinica. 2026, 47(8): 217-224 https://doi.org/10.19912/j.0254-0096.tynxb.2025-0626

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