Neuro-Transistor Based on UV-Treated Charge Trapping in MoTe2 for Artificial Synaptic Features

Abstract

The diversity of brain functions depend on the release of neurotransmitters in chemical synapses. The back gated three terminal field effect transistors (FETs) are auspicious candidates for the emulation of biological functions to recognize the proficient neuromorphic computing systems. In order to encourage the hysteresis loops, we treated the bottom side of MoTe2 flake with deep ultraviolet light in ambient conditions. Here, we modulate the short-term and long-term memory effects due to the trapping and de-trapping of electron events in few layers of a MoTe2 transistor. However, MoTe2 FETs are investigated to reveal the time constants of electron trapping/de-trapping while applying the gate-voltage pulses. Our devices exploit the hysteresis effect in the transfer curves of MoTe2 FETs to explore the excitatory/inhibitory post-synaptic currents (EPSC/IPSC), long-term potentiation (LTP), long-term depression (LTD), spike timing/amplitude-dependent plasticity (STDP/SADP), and paired pulse facilitation (PPF). Further, the time constants for potentiation and depression is found to be 0.6 and 0.9 s, respectively which seems plausible for biological synapses. In addition, the change of synaptic weight in MoTe2 conductance is found to be 41% at negative gate pulse and 38% for positive gate pulse, respectively. Our findings can provide an essential role in the advancement of smart neuromorphic electronics.

Implementation of Synaptic Device Using Ultraviolet Ozone Treated Water‐in‐Bisalt/Polymer Electrolyte‐Gated Transistor

“…[15][16][17] Also, UVO treatment is one of the representative post-treatment that has been widely applied to surface modification in various fields. [18][19][20] We performed hysteresis analysis and X-ray photoelectron spectroscopy (XPS) analysis to determine the cause of the improvement in long-term plasticity performance. Since surface trap sites of IGZO generated by the UVO treatment can interact with lithium cations at the interface, the overall performance of the WEST is improved.…”

An artificial synaptic transistor using an α-In2Se3 van der Waals ferroelectric channel for pattern recognition

“…6 For an articial synaptic device to be effectively used in an ANN, it is desirable that it includes linearly spaced conductance weight states, high endurance, longer retention and low energy consumption. To date, multiple device concepts have been proposed to realize articial synapse, such as resistive random access memristors (RRAMs), 7,8 phase-change memory (PCM), 9 charge trapping transistors, 10 ion movement in electrolytes, 11 and ferroelectric based devices with excellent performance and high integration capability. However, solid state devices are far from even remotely reaching the performance of actual biological synapse.…”

Flexible Nonvolatile Bioresistive Random Access Memory with an Adjustable Memory Mode Capable of Realizing Logic Functions

“…RRAM is considered a potential candidate solution for overcoming the von Neumann bottleneck [ 4 ]. Emerging 2D materials have received more and more attention in the preparation of memristors due to their unique structures and properties, such as flexible and wearable devices, and neural networks [ 5 , 6 , 7 ]. Memory devices prepared with metal oxides [ 8 , 9 , 10 , 11 ], organic polymers [ 12 , 13 , 14 , 15 ], perovskites [ 16 , 17 , 18 , 19 ], and other materials as active layers still have major deficiencies in terms of sustainable use and biocompatibility.…”