Optimization of ink-jet printed precursors for Cu^sub 2^ZnSn(S,Se)^sub 4^ solar cells

• Published in: Journal of alloys and compounds 2018-02, Vol.735, p.2462
• Main Authors: Colina, M, Bailo, E, Medina-Rodríguez, B, Kondrotas, R, Sánchez-González, Y, Sylla, D, Placidi, M, Blanes, M, Ramos, F, Cirera, A, Rodríguez, A Pérez, Saucedo, E
• Format: Article
• Language: English
• Subjects: Deposition; Drying; Glass substrates; Ink jet printers; Inkjet printing; Masks; Optimization; Photovoltaic cells; Physical properties; Precursors; Soda-lime glass; Solar cells; Spin coating; Thin films
• ISSN: 0925-8388; 1873-4669

Cu2ZnSn(S,Se)4 (CZT(S,Se)) solution-based solar cells are currently drawing the attention of the photovoltaic (PV) community due to their promising efficiencies and the low-cost strategies. Although the best results were achieved by using spin coating, techniques with better controlled deposition and significantly lower material waste, such as inkjet printing, can enhance the solution-based potential. Furthermore, inkjet printing also includes the capability to write specific patterns without the use of masks or scribing tools for series interconnection of modules. In this work, a precursor ink composed by metallic salts in DMSO was optimized in terms of salts concentration and physical properties for the deposition of CZTS films onto molybdenum coated soda lime glass substrates by means of inkjet printing. In order to synthesize the solid precursor, the CZTS solution was deposited layer by layer to obtain different thicknesses using printing cycles with drying step in between. The drying temperature was also varied to evaluate the precursor morphology and its impact on the photovoltaic response of the films. Likewise, the effect of the number of cycles was also evaluated. Finally, CZTSSe solar cells were fabricated with a maximum efficiency of 6.55% without metal grid and anti-reflection layer, demonstrating the high potential of the strategy of this work.