Maskless fabrication of quasi-omnidirectional V-groove solar cells using an alkaline solution-based method

Abstract

Silicon passivated emitter and rear contact (PERC) solar cells with V-groove texture were fabricated using maskless alkaline solution etching with in-house developed additive. Compared with the traditional pyramid texture, the V-groove texture possesses superior effective minority carrier lifetime, enhanced p–n junction quality and better applied filling factor (FF). In addition, a V-groove texture can greatly reduce the shading area and edge damage of front Ag electrodes when the V-groove direction is parallel to the gridline electrodes. Due to these factors, the V-groove solar cells have a higher efficiency (21.78%) than pyramid solar cells (21.62%). Interestingly, external quantum efficiency (EQE) and reflectance of the V-groove solar cells exhibit a slight decrease when the incident light angle (θ) is increased from 0° to 75°, which confirms the excellent quasi omnidirectionality of the V-groove solar cells. The proposed V-groove solar cell design shows a 2.84% relative enhancement of energy output over traditional pyramid solar cells.