Performance of Large Area n-TOPCon Solar Cells with Selective Poly-Si Based Passivating Contacts Prepared by PECVD Method

Zhaobin Liu; Chunlin Guo; Ya Liu; Jianhua Wang; Xuping Su; Qinqin Wang

doi:10.3390/ma17040849

Performance of Large Area n-TOPCon Solar Cells with Selective Poly-Si Based Passivating Contacts Prepared by PECVD Method

Materials (Basel). 2024 Feb 9;17(4):849. doi: 10.3390/ma17040849.

Authors

Zhaobin Liu^{1

2}, Chunlin Guo³, Ya Liu^{1

2}, Jianhua Wang^{1

2}, Xuping Su^{1

2}, Qinqin Wang⁴

Affiliations

¹ School of Materials Science and Engineering, Changzhou University, Changzhou 213164, China.
² Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China.
³ Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China.
⁴ Institute of Technology for Carbon Neutralition, Yangzhou University, Yangzhou 225009, China.

Abstract

Selective emitter (SE) technology significantly influences the passivation and contact properties of n-TOPCon solar cells. In this study, three mask layers (SiO_x, SiN_x, and SiO_xN_y) were employed to fabricate n-TOPCon solar cells with phosphorus (P)-SE structures on the rear side using a three-step method. Additionally, phosphosilicon glass (PSG) was used to prepare n-TOPCon solar cells with P-SE structure on the rear side using four-step method, and the comparative analysis of electrical properties were studied. The SiO_x mask with a laser power of 20 W (O2 group) achieved the highest solar cell efficiency (E_ff, 24.85%), The open-circuit voltage (V_oc) is 2.4 mV higher than that of the H1 group, and the fill factor (FF) is 1.88% higher than that of the L1 group. Furthermore, the final E_ff of solar cell is 0.17% higher than that of the L1 group and 0.20% higher than that of the H1 group. In contrast, using the four-step method and a laser power of 20 W (P2 group), a maximum E_ff of 24.82% was achieved. Moreover, it exhibited an V_oc, which is elevated by 3.2 mV compared to the H1 group, and FF increased by 1.49% compared to the L1 group. Furthermore, the overall E_ff of the P2 group outperforms both the L1 and H1 groups by approximately 0.14% and 0.17%, respectively. In the four-step groups, the E_ff of each laser condition group was improved compared with the L1 group and H1 group, The stability observed within the four-step method surpassed that of the three-step groups. However, in terms of full-scale electrical properties, the three-step method can achieve comparable results as those obtained from the four-step method. This research holds significant guiding implications for upgrading the n-TOPCon solar cell rear-side technology during mass production.

Keywords: P-SE; laser; mask; n-TOPCon.

Grants and funding

This research was funded by the Priority Academic Program Development of Jiangsu higher education institutions is gratefully acknowledged. Additionally, this work also has received partial funding from the National Natural Science Foundation youth project (62304199) and the National Key Research and Development Program of China (2023YFB4202600).