Regulating the p-n interface quality for Sb2Se3-based quasi-homojunction thin film solar cells by an effective two-step heat treatment process

• Published in: Journal of alloys and compounds Vol. 960; p. 170753
• Main Authors: Ren, Donglou, Li, Chen, Li, Zhicheng, Zhu, Bin, Fu, Boyang, Ji, Jingwei, Chen, Shuo, Liang, Guangxing, Ma, Hongli, Zhang, Xianghua
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.10.2023; Elsevier
• Subjects: Chemical Sciences; Quasi-homojunction solar cells; Sb2Se3; SCAPS-1D; Sputtering; Two-step heat treatment; Sb2Se3; Quasi-homojunction solar cells; Two-step heat treatment; Sputtering; SCAPS-1D
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2023.170753

Earth-abundant Sb2Se3 material has received an increased attention from photovoltaics community thanks to its excellent photo-electronic properties. Despite the fact that the Sb2Se3 heterojunction solar cells have obtained a rapid development, the serious interface defects have not been fundamentally solved so far. By contrast, the quasi-homojunction has advantages over heterojunction in terms of electronic property, however, its development is quite slow. Herein, the Sb2Se3-based quasi-homojunction devices with the configuration of SLG/FTO/Cu-Sb2Se3/I-Sb2Se3/Al have been fabricated using magnetron sputtering accompanied by a two-step heat treatment process. The relationship between the p-n interface quality and the device performances was investigated in detail. Thanks to the very well p-n interface, the devices achieved a 2.64% PCE, with ∼ 10% improvement compared with the devices fabricated via one-step heat treatment, as previous reported. Moreover, an effective p- and n-type doping with high carrier density is essential for fabricating the efficient p-n interface, as evidenced by SCAPS simulations. Through the co-optimization of various device parameters, the predicted PCE of quasi-homojunction devices can reach 18.96%, using the Mg as back contact, leading to lower minority carrier recombination at near the back-contact. Eventually, the simulation indicated clearly the directions for further promoting cell performances by doping strategy. This work can provide valuable guidance for the further development and improvement of Sb2Se3-based quasi-homojunction thin-film solar cells. [Display omitted] •Sb2Se3-based quasi-homojunction devices were successfully fabricated.•Regulating the p-n interface quality with ∼ 10% improvement in PCE.•Device modeling was full performed by SCAPS.•p- and n-type high doped Sb2Se3 are essential for the efficient p-n interface.•The highest PCE of 18.96% was expected.