Exploring “No Man's Land”—Arrhenius Crystallization of Thin-Film Phase Change Material at 1 000 000 K s−1 via Nanocalorimetry

8Citations
Citations of this article
14Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Non-volatile phase-change memory (PCM) devices are based on phase-change materials such as Ge2Sb2Te5(GST). PCM requires critically high crystallization growth velocity (CGV) for nanosecond switching speeds, which makes its material-level kinetics investigation inaccessible for most characterization methods and remains ambiguous. In this work, nanocalorimetry enters this “no-man's land” with scanning rate up to 1 000 000 K s−1 (fastest heating rate among all reported calorimetric studies on GST) and smaller sample-size (10–40 nm thick) typical of PCM devices. Viscosity of supercooled liquid GST (inferred from the crystallization kinetic) exhibits Arrhenius behavior up to 290 °C, indicating its low fragility nature and thus a fragile-to-strong crossover at ≈410 °C. Thin-film GST crystallization is found to be a single-step Arrhenius process dominated by growth of interfacial nuclei with activation energy of 2.36 ± 0.14 eV. Calculated CGV is consistent with that of actual PCM cells. This addresses a 10-year-debate originated from the unexpected non-Arrhenius kinetics measured by commercialized chip-based calorimetry, which reports CGV 103−105 higher than those measured using PCM cells. Negligible thermal lag (<1.5 K) and no delamination is observed in this work. Melting, solidification, and specific heat of GST are also measured and agree with conventional calorimetry of bulk samples.

Cite

CITATION STYLE

APA

Zhao, J., Hui, J., Ye, Z., Lai, T., Efremov, M. Y., Wang, H., & Allen, L. H. (2022). Exploring “No Man’s Land”—Arrhenius Crystallization of Thin-Film Phase Change Material at 1 000 000 K s−1 via Nanocalorimetry. Advanced Materials Interfaces, 9(23). https://doi.org/10.1002/admi.202200429

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free