A hole-dominated highly sensitive position-sensitive detector based on a MAPbI3 heterojunction

Abstract

CH₃NH₃(MA)PbI₃, a typical material of organic-inorganic hybrid perovskites, possesses essential electrical and optoelectronic properties, such as a direct band gap, long carrier diffusion length, and high absorption coefficient, making it ideal for high-performance photoelectric devices. While recent advancements have achieved in perovskite-based photodetectors, the utilization of MAPbI₃ in position-sensitive detectors (PSDs) remains unknown. In this work, we develop a PSD using a Spiro-OMeTAD/MAPbI₃ heterostructure, demonstrating a lateral photovoltaic response spanning 405 to 780 nm under zero bias and non-uniform laser irradiation. Notably, the PSD shows an ultra-low power detection range of 1 to 10 μW, with an optimal position sensitivity of 494.38 mV/mm and nonlinearity of <11.87% at 671 nm. Moreover, the Spiro-OMeTAD/MAPbI₃ heterojunction PSD exhibits remarkable stability across various frequencies, with response times of 1.243/0.52 ms. By adjusting the electrode space from 0.3 to 2.9 mm, the PSD's response shows a decreasing trend while maintaining a significant position sensitivity of 132.78 mV/mm at 2.9 mm. Leveraging this unique characteristic, we successfully implement an intensity-modulated optical mapping capability.