Artificial Synapse Based on an InAs Nanowire Field-Effect Transistor with Ferroelectric Polymer P(VDF-TrFE) Passivation

Indium arsenide (InAs) nanowire (NW) is a promising semiconductor material in modern electronic and optoelectronic devices due to its fascinating properties such as narrow direct band gap, high mobility, etc. However, the surface and interface properties are the major factors limiting the performance of InAs NW devices. Here, we demonstrate an approach to improve the performance of InAs NW field-effect transistor (FET) by passivating the NW surface with ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)). After the ferroelectric film coating, the maximum field-effect mobility reaches 6547 cm² V^–1 s^–1 and the minimum subthreshold swing is 178 mV dec^–1, which is the best performance among the reported InAs NW FET with global back-gated structure. Additionally, synaptic behavior is observed for the first time in an InAs NW FET with P(VDF-TrFE) passivation. Typical synaptic functions are successfully simulated, including postsynaptic current (PSC), paired-pulse facilitation (PPF), and multiple-spike response. In addition, the energy consumption of our synaptic devices is only 230 fJ per synaptic event at 0.1 V, approaching the biological synapse level (∼10 fJ). This work is of great significance for developing low-power, high-speed, and biomimetic plasticity artificial synapses based on III–V NWs.