Effect of the Thermal Conductivity on Resistive Switching in GeTe and Ge2Sb2Te5 Nanowires

Sungjin Park, Dambi Park, Kwangsik Jeong, Taeok Kim, Seungjong Park, Min Ahn, Won Jun Yang, Jeong Hwa Han, Hong Sik Jeong, Seong Gi Jeon, Jae Yong Song, Mann-Ho Cho

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

The thermal conduction characteristics of GeTe and Ge2Sb2Te5(GST) nanowires were investigated using an optical method to determine the local temperature by Raman spectroscopy. Since the localization of surface charge in a single-crystalline nanostructure can enhance charge-phonon scattering, the thermal conductivity value (κ) of single crystalline GeTe and GST nanowires was decreased significantly to 1.44 Wm-1 K-1 for GeTe and 1.13 Wm-1 K-1 for GST, compared to reported values for polycrystalline structures. The SET-to-RESET state in single-crystalline GeTe and GST nanowires are characteristic of a memory device. Unlike previous reports using GeTe and GST nanowires, the SET-to-RESET characteristics showed a bipolar switching shape and no unipolar switching. In addition, after multiple cycles of operation, a significant change in morphology and composition was observed without any structural phase transition, indicating that atoms migrate toward the cathode or anode, depending on their electronegativities. This change caused by a field effect indicates that the structural phase transition does not occur in the case of GeTe and GST nanowires with a significantly lowered thermal conductivity and stable crystalline structure. Finally, the formation of voids and hillocks as the result of the electromigration critically degrades device reliability.

Original languageEnglish
Pages (from-to)21819-21827
Number of pages9
JournalACS Applied Materials and Interfaces
Volume7
Issue number39
DOIs
Publication statusPublished - 2015 Oct 7

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Materials Science(all)

Cite this

Park, S., Park, D., Jeong, K., Kim, T., Park, S., Ahn, M., Yang, W. J., Han, J. H., Jeong, H. S., Jeon, S. G., Song, J. Y., & Cho, M-H. (2015). Effect of the Thermal Conductivity on Resistive Switching in GeTe and Ge2Sb2Te5 Nanowires. ACS Applied Materials and Interfaces, 7(39), 21819-21827. https://doi.org/10.1021/acsami.5b05703