Memristive Memory Enhancement by Device Miniaturization for Neuromorphic Computing

The areal footprint of memristors is a key consideration in material-based neuromorphic computing and large-scale architecture integration. Electronic transport in the most widely investigated memristive devices is mediated by filaments, posing a challenge to their scalability in architecture implementation. Here, a compelling alternative memristive device is presented and it is demonstrated that areal downscaling leads to enhancement in the memristive memory window, while maintaining analog behavior, contrary to expectations. The device designs directly integrated on semiconducting Nb-doped SrTiO3 (Nb:STO) allows leveraging electric field effects at edges, increasing the dynamic range in smaller devices. The findings are substantiated by studying the microscopic nature of switching using scanning transmission electron microscopy, in different resistive states, revealing an interfacial layer whose physical extent is influenced by applied electric fields. The ability of Nb:STO memristors to satisfy hardware and software requirements with downscaling, while significantly enhancing memristive functionalities, make them strong contenders for non-von-Neumann computing, beyond complementary metal-oxide-semiconductor.

Automated summary

This study presents a compelling alternative memristive device that shows enhanced memristive memory window and maintained analog behavior through areal downscaling. By directly integrating the device designs on semiconducting Nb-doped SrTiO3, the electric field effects at edges are leveraged to increase the dynamic range in smaller devices. The findings also reveal the influence of applied electric fields on the physical extent of an interfacial layer, as observed through scanning transmission electron microscopy.