To move towards a new generation powerful computing system, brain-inspired neuromorphic computing is expected to transform the architecture of the conventional computer, where memristors are considered to be potential solutions for synapses part. We propose and demonstrate a novel approach to achieve remarkable improvement of analog switching linearity in TaN/Ta/TaO x /Al 2 O 3 /Pt/Si memristors by varying Al 2 O 3 layer thickness. Presence of the Al 2 O 3 layer is confirmed from the Auger Electron Spectroscopy study. Good analog switching ratio of about 100× and superior switching uniformity are observed for the 1 nm Al 2 O 3 based device. Multilevel capability of the memristive devices is also explored for prospective use as a synapse. More than 10 4 and 4 × 10 4 cycles nondegradable dc and ac endurances, respectively, alongwith 10 4 second retention are achieved for the optimized device. Improved linearities of 2.41 and −2.77 for potentiation and depression, respectively are obtained for such 1 nm Al 2 O 3-based devices. The property of gradual resistance changed by pulse amplitudes confirms that the TaO x memristors can be potentially used as an electronic synapse.