Milk–Ta2O5 Hybrid Memristors with Crossbar Array Structure for Bio-Organic Neuromorphic Chip Applications

Abstract

In this study, a high-performance bio-organic memristor with a crossbar array structure using milk as a resistive switching layer (RSL) is proposed. To ensure compatibility with the complementary metal oxide semiconductor process of milk RSL, a high-k Ta2O5 layer was deposited as a capping layer; this layer enables high-density, integration-capable, photolithography processes. The fabricated crossbar array memristors contain milk–Ta2O5 hybrid membranes, and they exhibit bipolar resistance switching behavior and uniform resistance distribution across hundreds of repeated test cycles. In terms of the artificial synaptic behavior and synaptic weight changes, milk–Ta2O5 hybrid crossbar array memristors have a stable analog RESET process, and the memristors are highly responsive to presynaptic stimulation via paired-pulse facilitation excitatory post-synaptic current. Moreover, spike-timing-dependent plasticity and potentiation and depression behaviors, which closely emulate long-term plasticity and modulate synaptic weights, were evaluated. Finally, an artificial neural network was designed and trained to recognize the pattern of the Modified National Institute of Standards and Technology (MNIST) digits to evaluate the capability of the neuromorphic computing system. Consequently, a high recognition rate of over 88% was achieved. Thus, the milk–Ta2O5 hybrid crossbar array memristor is a promising electronic platform for in-memory computing systems.

Effect of oxygen vacancy and Si doping on the electrical properties of Ta2O5 in memristor characteristics

“…One of the key advantages of Ta 2 O 5 as a memristor material is its ability to undergo resistive switching (RS), a phenomenon in which the resistance of the material can be switched between high and low states by applying an electric field. Ta 2 O 5 memristors, like other comparable metal oxides, are important due to their potential to revolutionize memory and computing technologies, facilitate new forms of artificial intelligence, curtail energy consumption, and empower the development of intricate and complex systems 8,9,[14][15][16][17] . Usually, the RS phenomenon in Ta 2 O 5 is attributed to the creation and disruption of conductive filaments (CFs) within the material, which can be controlled by the applied voltage and the presence of oxygen vacancies (OVs) [18][19][20] .…”