Fabrication of GaO x based crossbar array memristive devices and their resistive switching properties

Memristive devices attract much attention for the application to neuromorphic computing. Here we focus on amorphous GaOx based memristive devices and their integration as a crossbar architecture which is mandatory to improve parallelism in computing and essential to future power-saving, high-speed and reliable artificial neural networks (ANN). Fabricated Pt/GaOx/ITO crossbar array memristive devices with 3 x 3 mu m(2) crosspoints exhibit non-filamentary reversible bipolar resistive switching (RS) without any electroforming processes. We demonstrate the gradual resistance change by repeating voltage sweep and applying pulse voltages. The expression of spike-timing-dependent plasticity property, one of synaptic functions in neuromorphic devices, is also successful in the present device. The obtained results strongly suggest that the drift of oxygen vacancies in GaOx plays an important role in the RS behavior and the GaOx based crossbar array memristive devices have a great potential for hardware implementation of ANN. (C) 2020 The Japan Society of Applied Physics