Study On The Electrical Properties Of A Novel Organic Iron Field Effect Memristor

Memristor is a kind of resistance switch that dynamically changes its internal resistance state based on the“memory”applied voltage or current history,which is an important candidate for future storage and massive parallelism and low-power operation in neuromorphic computation.However,state-of-the-art two-terminal memristor suffering from excessive write noise,abrupt resistance variation,inherently stochasticity,poor endurance and costly energy consumption.The signal transmission is carried via the channel and the synaptic weights presented by various channel conductance are modulated independently via the gate and drain terminals?information transmission and learning process?in the three-terminal memristor.In the construction of a large-scale array,transistor synaptic devices can largely avoid the phenomenon of sneak paths caused by parasitic currents and have the advantages of easier wiring in constructing a multiple input-output neural network.In order to realize the artifical synapses and neuromorphology computing and other functional advantages,this work develops a new artificial synapse based on a field-effect transistor incorporating a novel two-dimensional materials with an organic ferroelectric gate layer.The main research contents are as follows:1.At first,a double-gate FET was successfully fabricated by exploring experimental conditions and optimizing experimental parameters.A clear hysteresis,was observed in the transfer characteristic curve of a MoS₂-FETs with ferroelectric poly?vinylidene fluoride/trifluoroethylene?[P?VDF-TrFE?]gate layer.The field effect carrier mobility of MoS₂ nanoflakes reached approximately 95.6 cm²/Vs under the control of the polarization field of P?VDF-TrFE?,whereas the effect carrier mobility was only approximately 15.3 cm²/Vs in MoS₂-FETs with traditional dielectric poly?methylmethacrylate??PMMA?gate layer.Furthermore,the ferroelectric MoS₂-FETs possess a higher ON/OFF resistance ratio?approximately 10⁷?than the PMMA MoS₂-FETs?approximately 10⁵?.This experiment established the foundation for the next exploration of its related memristive properties.2.We demonstrated that modulation of the channel carrier concentration in MoS₂-FETs by pulse voltage-controlled ferroelectric polarization switching yield memristive behaviour with conductance variation exceeding 4 orders of magnitude and 10⁷ cycles enduration.Our results suggest a new opportunity for ferroelectrics combining 2D materials as a new class of memristive systems.The system is expected to provide experimental basis for the realization of learning functions in a complex synapses-based circuit.3.We demonstrate an organic ferroelectric transistor as a regulable artificial synapse in which the purely electronic mechanism associating with ferroelectric domain dynamics results in a steerable resistive switching within more than 100intermediate resistance states.Essential synaptic plasticity and learning behaviours including both spike-timing dependent plasticity?STDP?and spike-rate-dependent plasticity?SRDP?were emulated in a single device.The energy consumption for each synaptic operation can be reduced to few fJ.These performance gains and efficiency in the CMOS-compatible organic ferroelectric synapses open a path towards implementation of unsupervised learning in high-density memristive crossbar arrays.