Novel Type of Synaptic Transistors Based on a Ferroelectric Semiconductor Channel

Three-terminal synaptic transistors are basic units of neuromorphic computing chips, which may overcome the bottleneck of conventional von Neumann computing. So far, most of the three-terminal synaptic transistors use the dielectric layer to change the state of the channel and mimic the synaptic behavior. For this purpose, special dielectric layers are needed, such as ionic liquids, solid electrolytes, or ferroelectric insulators, which are difficult for miniaturization and integration. Here, we report a novel type of synaptic transistors using a two-dimensional ferroelectric semiconductor, i.e., alpha-In2Se3, as the channel material to mimic the synaptic behavior for the first time. The essential synaptic behaviors, such as single-spike response, paired-spike response, and multispike response have been experimentally demonstrated. Most importantly, the conventional gate dielectric material of our transistors may facilitate the miniaturization and batch manufacture of synaptic transistors. The results indicate that the three-terminal synaptic transistors based on two-dimensional ferroelectric semiconductors are very promising for neuromorphic systems.