Ultrathin and Conformable Lead Halide Perovskite Photodetector Arrays for Potential Application in Retina-Like Vision Sensing

Solution-processed lead halide perovskites are considered one of the promising materials for flexible optoelectronics. However, the array integration of ultrathin flexible perovskite photodetectors (PDs) remains a significant challenge limited by the incompatibility of perovskite materials with manufacturing techniques involving polar liquids. Here, an ultrathin (2.4 mu m) and conformable perovskite-based PD array (10 x 10 pixels) with ultralight weight (3.12 g m(-2)) and excellent flexibility, is reported. Patterned all-inorganic CsPbBr3 perovskite films with precise pixel position, controllable morphology, and homogenous dimension, are synthesized by a vacuum-assisted drop-casting patterning process as the active layer. The use of waterproof parylene-C film as substrate and encapsulation layer effectively protects the perovskite films against penetration of polar liquids during the peeling-off process. Benefitting from the encapsulation and ultrathin property, the device exhibits long-term stability in the ambient environment, and robust mechanical stability under bending or 50% compressive strain. More importantly, the ultrathin flexible PD arrays conforming to hemispherical support realize imaging of light distribution, indicating the potential applications in retina-like vision sensing.

Automated summary

Solution-processed lead halide perovskites are promising materials for flexible optoelectronics, but integrating ultrathin flexible perovskite photodetectors remains challenging due to compatibility issues with manufacturing techniques involving polar liquids. This study introduces an ultrathin and conformable perovskite-based PD array with precise pixel position and excellent flexibility, protected by a waterproof parylene-C film against penetration of polar liquids. The device exhibits long-term stability and robust mechanical stability, with potential applications in retina-like vision sensing.