Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu, 215123, P. R. China.
Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Taipa, Macau SAR, 999078, P. R. China.
Adv Mater. 2022 May;34(18):e2200380. doi: 10.1002/adma.202200380. Epub 2022 Mar 28.
Photosynaptic organic field-effect transistors (OFETs) represent a viable pathway to develop bionic optoelectronics. However, the high operating voltage and current of traditional photosynaptic OFETs lead to huge energy consumption greater than that of the real biological synapses, hindering their further development in new-generation visual prosthetics and artificial perception systems. Here, a fully solution-printed photosynaptic OFET (FSP-OFET) with substantial energy consumption reduction is reported, where a source Schottky barrier is introduced to regulate charge-carrier injection, and which operates with a fundamentally different mechanism from traditional devices. The FSP-OFET not only significantly lowers the working voltage and current but also provides extraordinary neuromorphic light-perception capabilities. Consequently, the FSP-OFET successfully emulates visual nervous responses to external light stimuli with ultralow energy consumption of 0.07-34 fJ per spike in short-term plasticity and 0.41-19.87 fJ per spike in long-term plasticity, both approaching the energy efficiency of biological synapses (1-100 fJ). Moreover, an artificial optic-neural network made from an 8 × 8 FSP-OFET array on a flexible substrate shows excellent image recognition and reinforcement abilities at a low energy cost. The designed FSP-OFET offers an opportunity to realize photonic neuromorphic functionality with extremely low energy consumption dissipation.
光突触有机场效应晶体管（OFET）代表了开发仿生光电子学的可行途径。然而，传统光突触 OFET 的高工作电压和电流导致了巨大的能量消耗，超过了真实生物突触的能量消耗，这阻碍了它们在新一代视觉假体和人工感知系统中的进一步发展。在这里，我们报道了一种具有显著能量消耗降低的全溶液印刷光突触 OFET（FSP-OFET），其中引入源肖特基势垒来调节电荷载流子注入，其工作机制与传统器件有根本的不同。FSP-OFET 不仅显著降低了工作电压和电流，而且提供了非凡的神经形态光感知能力。因此，FSP-OFET 成功模拟了视觉神经对外部光刺激的反应，其短期可塑性的每个尖峰的能量消耗为 0.07-34 fJ，长期可塑性的每个尖峰的能量消耗为 0.41-19.87 fJ，这两种情况都接近生物突触的能量效率（1-100 fJ）。此外，由柔性衬底上的 8×8 FSP-OFET 阵列制成的人工光神经网络以较低的能量成本显示出出色的图像识别和增强能力。设计的 FSP-OFET 为实现具有极低能量消耗的光子神经形态功能提供了机会。
