Highly uniform photonic synapse arrays based on TIPS-pentacene nanowires/CsPbBr3 heterojunctions

Abstract

Inspired by the biological visual system, the biomimetic visual systems are of great significance to integrate large-scale and small-scale organic photon synaptic sensors and further construct a neural form of an artificial visual system. However, there are still many unavoidable problems in fabricating synaptic transistor arrays with good integrity. Herein, we fabricated synaptic arrays based on CsPbBr₃ thin film/TIPS-pentacene nanowires. Thanks to the confinement effect of the template imprinting process on organic precursor solutions, the surface of the composite film was smooth and flat without obvious grain boundaries and the composite transistor on the synaptic array had ultra-high stability. High cycling stability of a single device was obtained, and the excellent overall consistency of steady-state leakage source current and good transient photocurrent of multiple devices under dark and light conditions were achieved. The light-to-dark current ratio of the synaptic array exceeded 8 × 10³ when the light was introduced. The average transient peak photocurrent of −14 nA was achieved. Based on the compact model of organic transistors, the experimental data was fitted to estimate the impact of light power changes on the photoelectronic performance of the device and evaluate the transient operating stability of different devices within the arrays. Based on a composite synaptic array, an artificial vision system was constructed to achieve image processing functions.