Nanothermal Characterization of Amorphous and Crystalline Phases in Chalcogenide Thin Films with Scanning Thermal Microscopy

TL;DR

This study uses scanning thermal microscopy to measure and compare the thermal properties of amorphous and crystalline phases in GeTe and Ge2Sb2Te5 chalcogenide thin films, crucial for phase change memory devices.

Contribution

It provides quantitative nanothermal characterization of phase change materials, estimating thermal conductivities and boundary conductances for both phases and two film thicknesses.

Findings

Thermal conductivities differ significantly between amorphous and crystalline phases.

Thermal boundary conductances are independently estimated for each phase.

Results inform the thermal management in phase change memory devices.

Abstract

The thermal properties of amorphous and crystalline phases in chalcogenide phase change materials (PCM) play a key role in device performance for non-volatile random-access memory. Here, we report the nanothermal morphology of amorphous and crystalline phases in laser pulsed GeTe and Ge2Sb2Te5 thin films by scanning thermal microscopy (SThM). By performing SThM measurements and applying quantitative physical models to two film thicknesses, the PCM thermal conductivities and thermal boundary conductances between the PCM and SThM probe are independently estimated for the amorphous and crystalline phase of each stoichiometry.