Inducing Chalcogenide Phase Change with Ultra-Narrow Carbon Nanotube Heaters

TL;DR

This paper demonstrates that ultra-narrow carbon nanotube heaters can induce localized phase change in chalcogenide materials at significantly lower currents than traditional methods, with potential for highly miniaturized phase change memory devices.

Contribution

The study introduces a novel approach using sub-5 nm CNT heaters to efficiently induce phase change in GST at ultra-low currents, advancing phase change memory technology.

Findings

Localized phase change in GST achieved with CNT heaters

Significant resistance reduction at low currents (~25 uA)

Finite element simulations match experimental results

Abstract

Carbon nanotube (CNT) heaters with sub-5 nm diameter induce highly localized phase change in Ge2Sb2Te5 (GST) chalcogenide. A significant reduction in resistance of test structures is measured as the GST near the CNT heater crystallizes. Effective GST heating occurs at currents as low as 25 uA, significantly lower than in conventional phase change memory with metal electrodes (0.1-0.5 mA). Atomic force microscopy reveals nucleation sites associated with phase change in GST around the CNT heater. Finite element simulations confirm electrical characteristics consistent with the experiments, and reveal the current and phase distribution in GST.