AUTHOR=Zarudnyi Konstantin , Mehonic Adnan , Montesi Luca , Buckwell Mark , Hudziak Stephen , Kenyon Anthony J. 

TITLE=Spike-Timing Dependent Plasticity in Unipolar Silicon Oxide RRAM Devices

JOURNAL=Frontiers in Neuroscience

VOLUME=Volume 12 - 2018

YEAR=2018

URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2018.00057

DOI=10.3389/fnins.2018.00057

ISSN=1662-453X

ABSTRACT=Resistance switching, or Resistive RAM (RRAM) devices show considerable potential for application in hardware spiking neural networks (neuro-inspired computing) by mimicking some of the behaviour of biological synapses, and hence enabling non-von Neumann computer architectures. Spike-timing depend-ent plasticity (STDP) is one such behaviour, and one example of several classes of plasticity that are being examined with the aim of finding suitable algorithms for application in many computing tasks such as co-incidence detection, classification and image recognition. In previous work we have demonstrated that the neuromorphic capabilities of silicon-rich silicon oxide (SiOx) resistance switching devices extend beyond plasticity to include thresholding, spiking and integration. We previously demonstrated such behaviours in devices operated in the unipolar mode, opening up the question of whether we could add plasticity to the list of features exhibited by our devices. Here we demonstrate clear STDP in unipolar devices. Significant-ly, we show that the response of our devices is broadly similar to that of biological synapses. This work further reinforces the potential of simple two-terminal RRAM devices to mimic neuronal functionality in hardware spiking neural networks.