Wang Yu-Fen, Lin Yen-Chuan, Wang I-Ting, Lin Tzu-Ping, Hou Tuo-Hung
Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, Hsinchu, Taiwan.
Sci Rep. 2015 May 8;5:10150. doi: 10.1038/srep10150.
A two-terminal analog synaptic device that precisely emulates biological synaptic features is expected to be a critical component for future hardware-based neuromorphic computing. Typical synaptic devices based on filamentary resistive switching face severe limitations on the implementation of concurrent inhibitory and excitatory synapses with low conductance and state fluctuation. For overcoming these limitations, we propose a Ta/TaOx/TiO2/Ti device with superior analog synaptic features. A physical simulation based on the homogeneous (nonfilamentary) barrier modulation induced by oxygen ion migration accurately reproduces various DC and AC evolutions of synaptic states, including the spike-timing-dependent plasticity and paired-pulse facilitation. Furthermore, a physics-based compact model for facilitating circuit-level design is proposed on the basis of the general definition of memristor devices. This comprehensive experimental and theoretical study of the promising electronic synapse can facilitate realizing large-scale neuromorphic systems.
一种能够精确模拟生物突触特征的双端模拟突触器件有望成为未来基于硬件的神经形态计算的关键组件。基于丝状电阻开关的典型突触器件在实现具有低电导和状态波动的并发抑制性和兴奋性突触方面面临严重限制。为了克服这些限制，我们提出了一种具有卓越模拟突触特征的Ta/TaOx/TiO2/Ti器件。基于氧离子迁移引起的均匀（非丝状）势垒调制的物理模拟准确地再现了突触状态的各种直流和交流演变，包括尖峰时间依赖可塑性和双脉冲易化。此外，基于忆阻器器件的一般定义，提出了一种便于电路级设计的基于物理的紧凑模型。对这种有前景的电子突触进行的全面实验和理论研究有助于实现大规模神经形态系统。
