Recent advances in oxide-based synaptic transistors for neuromorphic applications

With the increasing demand for processing massive and unstructured data, computing systems based on the von Neumann architecture are facing challenges of low-speed and high-energy consumption. Neuromorphic devices with synaptic functions are gradually emerging, which provides hardware support for the construction of brain-like computing systems. As an important branch of neuromorphic devices, synaptic transistors have shown great potential in energy-efficient parallel computing. Among the various types of synaptic transistors, oxide-based synaptic transistors (OSTs) have attracted widespread attention due to their compatibility with silicon technology and operating stability. Herein, the basic functionalities and the latest developments of OSTs are introduced. According to different operating mechanisms, OSTs are classified as electrolyte-gated synaptic transistors, ferroelectric synaptic transistors, charge trapping synaptic transistors, and photoelectric synaptic transistors. The material selection, device configuration, and synaptic characteristics of various devices are discussed. The application scenarios of OSTs in various fields are summarized. Finally, the development prospects of OSTs that could be significant for constructing neuromorphic systems are outlined.