Substrate Dependent Resistive Switching in Amorphous-HfOx Memristors: An Experimental and Computational Investigation

TL;DR

This study investigates how substrate thermal properties influence the performance of amorphous-HfOx memristors, demonstrating that low thermal conductivity substrates improve switching behavior and endurance through combined experimental and computational analysis.

Contribution

It provides the first comprehensive experimental and computational analysis of substrate-dependent thermal effects on HfOx memristor performance.

Findings

Glass substrates yield lower reset voltage and wider memory window.

Devices on glass show better endurance than on SiO2/Si.

Thermal environment significantly impacts memristor operation.

Abstract

While two-terminal HfOX (x<2) memristor devices have been studied for ion transport and current evolution, there have been limited reports on the effect of the long-range thermal environment on their performance. In this work, amorphous-HfOX based memristor devices on two different substrates, thin SiO2(280 nm)/Si and glass, with different thermal conductivities in the range from 1.2 to 138 W/m-K were fabricated. Devices on glass substrates exhibit lower reset voltage, wider memory window and, in turn, a higher performance window. In addition, the devices on glass show better endurance than the devices on the SiO2/Si substrate. These devices also show non-volatile multi-level resistances at relatively low operating voltages which is critical for neuromorphic computing applications. A Multiphysics COMSOL computational model is presented that describes the transport of heat, ions and electrons in these structures. The combined experimental and COMSOL simulation results indicate that the long-range thermal environment can have a significant impact on the operation of HfOx-based memristors and that substrates with low thermal conductivity can enhance switching performance.