N‐Doped ZnSnO Optoelectronic Synaptic Thin Film Transistors with Enhanced Visible‐Light Response

In this work, nitrogen‐doped zinc‐tin‐oxygen (ZnSnO:N) optoelectronic synaptic thin film transistors (TFTs) with superior visible light response are fabricated. Nitrogen doping narrows the bandgap of ZnSnO, which in turn broadens the absorption spectrum. Additionally, the reduction of non‐radiative centers in the channel layer prolongs the lifetime of the photogenerated electrons, resulting in enhancements to the photo response throughout the visible region. Optoelectronic synaptic devices based on ZnSnO:N TFTs can accurately replicate synaptic behaviors, including short‐term plasticity (STP) and long‐term plasticity (LTP). Furthermore, the ZnSnO:N optoelectronic synaptic TFT‐based array has the potential to improve image contrast. The ZnSnO:N TFT exhibits a considerable improvement in both visible light photosensitivity and synaptic plasticity.