Title
Polymorphism of GeSbTe superlattice nanowires
Document Type
Article
Publication Date
2-13-2013
Abstract
Scaling-down of phase change materials to a nanowire (NW) geometry is critical to a fast switching speed of nonvolatile memory devices. Herein, we report novel composition-phase-tuned GeSbTe NWs, synthesized by a chemical vapor transport method, which guarantees promising applications in the field of nanoscale electric devices. As the Sb content increased, they showed a distinctive rhombohedral-cubic-rhombohedral phase evolution. Remarkable superlattice structures were identified for the Ge8Sb 2Te11, Ge3Sb2Te6, Ge 3Sb8Te6, and Ge2Sb 7Te4 NWs. The coexisting cubic-rhombohedral phase Ge 3Sb2Te6 NWs exhibited an exclusively uniform superlattice structure consisting of 2.2 nm period slabs. The rhombohedral phase Ge3Sb8Te6 and Ge2Sb 7Te4 NWs adopted an innovative structure; 3Sb2 layers intercalated the Ge3Sb2Te6 and Ge 2Sb1Te4 domains, respectively, producing 3.4 and 2.7 nm period slabs. The current-voltage measurement of the individual NW revealed that the vacancy layers of Ge8Sb2Te11 and Ge3Sb2Te6 decreased the electrical conductivity. © 2013 American Chemical Society.
Publication Source (Journal or Book title)
Nano Letters
First Page
543
Last Page
549
Recommended Citation
Jung, C., Kim, H., Im, H., Seo, Y., Park, K., Back, S., Cho, Y., Kim, C., Park, J., & Ahn, J. (2013). Polymorphism of GeSbTe superlattice nanowires. Nano Letters, 13 (2), 543-549. https://doi.org/10.1021/nl304056k