Enhanced Synaptic Linearity in ZnO-Based Invisible Memristive Synapse by Introducing Double Pulsing Scheme

The synaptic plasticity of indium tin oxide (ITO)/ZnO/ITO highly transparent (more than 88%) analog switching resistive memory device is investigated. Highly stable analog switching behavior for more than 2500 cycles with a good memory window of approximately two orders makes it suitable for synapse application. The synaptic response is investigated by applying identical electrical pulses. The potentiation and depression of the device used the conventional identical single-pulse scheme to perform high nonlinearity (0.83) and decaying training epochs. However, the linearity and the training epochs are improved to 0.44 by implementing the identical double-pulse scheme. The proposed double-pulse scheme offers a broad dynamic range (200) having 320 conductance states. This invisible structure and double-pulse scheme can be highly suitable for the neuromorphic computing devices.