Back-contact perovskite solar cell fabrication via microsphere lithography. (November 2022) - Deng, Siqi
Abstract: Back-contact electrodes for hybrid organic-inorganic perovskite solar cells (PSCs) eliminate the parasitic absorption losses caused by the transparent conductive electrodes that are inherent to conventional sandwich-architecture devices. However, the fabrication methods for these unconventional architectures rely heavily on expensive photolithography, which limits scalability. Herein, we present an alternative cost-effective microfabrication technique in which the conventional photolithography process is replaced by microsphere lithography in which a close-packed polystyrene microsphere monolayer acts as the patterning mask for the honeycomb-shaped electrodes. A comprehensive comparison between photolithography and microsphere lithography fabrication techniques was conducted. Using microsphere lithography, we achieve highly efficient devices having a stabilized power conversion efficiency (PCE) of 8.6%, twice the reported value using photolithography. Microsphere lithography also enabled the fabrication of the largest back-contact PSC to date, having an active area of 0.75 cm 2 and a stabilized PCE of 2.44%. Graphical Abstract: Low-cost and scalable microsphere lithography enables back-contact perovskite solar cells with a stabilized power output of 8.6% ga1 Highlights: Efficient back-contact perovskite solar cell (BC-PSC) fabricated without the need for high-cost photolithography. Highest stabilized PCE at 8.6% for a polycrystalline BC-PSC fabricated via a photolithography-free method. Superior back-contact electrode morphology and smaller feature size using microsphere lithography. Featuring device having the largest active area for a BC-PSC at 0.75 cm 2 . In-depth charge-carrier dynamics analysis revealing charge extraction and interfacial properties in BC-PSC.