Application of SiOxNy films in industrial bifacial PERC solar cells

• Published in: Solar energy materials and solar cells Vol. 230; p. 111199
• Main Authors: Ma, S., Tang, H.B., Li, Z.P., Kong, X.Y., Shen, W.Z.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15-09-2021; Elsevier BV
• Subjects: Amorphous silicon; Bifacial p-Si PERCs; Corrosion effects; Efficiency; Emitters; Modules; Photovoltaic cells; Potential induced degradation; Silicon; Silicon oxynitride; SiOxNy; Solar cells; Bifacial p-Si PERCs; SiOxNy; Efficiency; Potential induced degradation
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2021.111199

The bifacial p-type silicon (p-Si) passivated emitter and rear cells (PERCs) have dominated the industrial bifacial solar cells. In this paper, we have investigated the impact of hydrogenated amorphous silicon oxynitride (SiOxNy) films on the optical and electrical performance of bifacial p-Si PERCs. Simulation and characterization are carried out to show the improvement of bifacial p-Si PERCs, yielding an absolute front-side efficiency improvement of 0.14% and 016% with SiOxNy films introduced to the front-side and rear-side, respectively. When SiOxNy films are employed to both sides of bifacial p-Si PERCs, the front-side and rear-side efficiency separately increase by 0.27% and 0.26% compared to the baseline without SiOxNy films. We have achieved on the bifacial p-Si PERCs production line an averaged front-side efficiency of 23.23% (champion efficiency of 23.42%), together with a 17.31% averaged rear-side efficiency. Furthermore, the introduction of SiOxNy films has been demonstrated to reduce the rear-side potential induced degradation (PID) effect through both single-cell modules and commercial glass-glass modules, due to the SiOxNy films protecting AlOx from corrosion and maximizing the field-effect passivation of AlOx layers.
•An absolute front-side efficiency improvement of 0.14% and 016% is achieved with SiOxNy films introduced to the front-side and rear-side of bifacial p-Si PERCs, respectively. When SiOxNy films are employed to both sides, the front-side and rear-side efficiency separately increase by 0.27% and 0.26% compared to the baseline without SiOxNy films. Finally an averaged front-side efficiency of 23.23% (champion efficiency of 23.42%) is achieved.•The introduction of SiOxNy films has been demonstrated to reduce the rear-side PID effect through both single-cell modules and commercial glass-glass modules, due to the SiOxNy films protecting AlOx from corrosion and maximizing the field-effect passivation of AlOx layers.