Polydopamine-assisted pixeled lead-free perovskite photosensors array

Abstract

Perovskite is a promising photosensor material for direct integration on integrated circuit (IC) chips due to the low-temperature growth process. However, the pixeled perovskite integration technology for high-resolution imaging faces challenges because of the poor perovskite stability and complex substrates. This work demonstrates a pixeled perovskite integration method on complex substrates with polydopamine (PDA)-assisted hydrophilic-hydrophobic treatment. Compared with conventional hydrophilic-hydrophobic treatment, the rich functional group in PDA can endow patterned wetting-dewetting regions on complex substrates. Besides, the proper band alignment between PDA and perovskite film enables a 6.8-fold suppression of dark current and a detectivity improvement from 1.6 × 1010 to 5.8 × 1010 Jones. We demonstrate the pixeled Cs2AgBiBr6 perovskite photosensor array in SiO2-Au hybrid substrates and confirm the optical imaging function. These results can contribute to the direct integration of photosensors on IC chips in the future.