2, GIST, Gwangju, , Korea (the Republic of)
3, University of Chinese Academy of Sciences, Beijing, , China
Organic-inorganic hybrid perovskite solar cells (PeSCs) are a promising solar technology with rapidly increasing power conversion efficiency (PCE). One of the key advantages of PeSCs is their solution processability. This allows PeSCs to be manufactured by cost-effective industrial roll-to-roll processes. However, rapid progress in the technology has been predominantly made by spin coating, a laboratory process that is not compatible/transferable to the roll-to-roll process. Typically, only a small fraction of reported processes developed by spin coating are applicable to the roll-to-roll process and, therefore, process re-optimization is required for the roll-to-roll process. CSIRO has been developing deposition processes by roll-to-roll compatible deposition methods and actual roll-to-roll processes. In this presentation, various approaches used in slot die coating of perovskite layers in batch and roll-to-roll processes will be presented. To realize a defect-free uniform perovskite layer, various deposition parameters including deposition temperature, coating speed, additives and drying methods are optimized. The sequential deposition process was modified to be suitable for the roll-to-roll process, producing PeSCs on flexible substrate with up to 11% PCE. The more ideal one-step deposition was also developed by additive and blowing-assisted slot die coating, and roll-to-roll produced PeSCs showed over 11% PCE without hysteresis. Hot deposition has also been found to be suitable in the roll-to-roll process. Recent progress on this process will be also presented.