Low Power MoS<sub>2</sub>/Nb<sub>2</sub>O<sub>5</sub> Memtransistor Device with Highly Reliable Heterosynaptic Plasticity
Jae Hyeon Nam, Se‐Young Oh, Hye Yeon Jang, Ojun Kwon, Heejeong Park, Woojin Park, Jung‐Dae Kwon, Yonghun Kim, Byungjin Cho
Abstract
Abstract Artificial synapses based on 2D MoS 2 memtransistors have recently attracted considerable attention as a promising device architecture for complex neuromorphic systems. However, previous memtransistor devices occasionally cause uncontrollable analog switching and unreliable synaptic plasticity due to random variations in the field‐induced defect migration. Herein, a highly reliable 2D MoS 2 /Nb 2 O 5 heterostructure memtransistor device is demonstrated, in which the Nb 2 O 5 interlayer thickness is a critical material parameter to induce and tune analog switching characteristics of the 2D MoS 2 . Ultraviolet photoelectron spectroscopy and photoluminescence analyses reveal that the Schottky barrier height at the 2D channel–electrode junction of the MoS 2 /Nb 2 O 5 heterostructure films is increased, leading to more effective contact barrier modulation and allowing more reliable resistive switching. The 2D/oxide memtransistors attain dual‐terminal (drain and gate) stimulated heterosynaptic plasticity and highly precise multi‐states. In addition, the memtransistor devices show an extremely low power consumption of ≈6 pJ and reliable potentiation/depression endurance characteristics over 2000 pulses. A high pattern recognition accuracy of ≈94.2% is finally achieved from the synaptic plasticity modulated by the drain pulse configuration using an image pattern recognition simulation. Thus, the novel 2D/oxide memtransistor makes a potential neuromorphic circuitry more flexible and energy‐efficient, promoting the development of more advanced neuromorphic systems.