1. Quasicrystalline phase-change memory.
- Author
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Lee, Eun-Sung, Yoo, Joung E., Yoon, Du S., Kim, Sung D., Kim, Yongjoo, Hwang, Soobin, Kim, Dasol, Jeong, Hyeong-Chai, Kim, Won T., Chang, Hye J., Suh, Hoyoung, Ko, Dae-Hong, Cho, Choonghee, Choi, Yongjoon, Kim, Do H., and Cho, Mann-Ho
- Subjects
PHASE change memory ,PHASE change materials ,CRYSTAL structure ,PHASE transitions ,THERMAL stability ,SUPERLATTICES - Abstract
Phase-change memory utilizing amorphous-to-crystalline phase-change processes for reset-to-set operation as a nonvolatile memory has been recently commercialized as a storage class memory. Unfortunately, designing new phase-change materials (PCMs) with low phase-change energy and sufficient thermal stability is difficult because phase-change energy and thermal stability decrease simultaneously as the amorphous phase destabilizes. This issue arising from the trade-off relationship between stability and energy consumption can be solved by reducing the entropic loss of phase-change energy as apparent in crystalline-to-crystalline phase-change process of a GeTe/Sb
2 Te3 superlattice structure. A paradigm shift in atomic crystallography has been recently produced using a quasi-crystal, which is a new type of atomic ordering symmetry without any linear translational symmetry. This paper introduces a novel class of PCMs based on a quasicrystalline-to-approximant crystalline phase-change process, whose phase-change energy and thermal stability are simultaneously enhanced compared to those of the GeTe/Sb2 Te3 superlattice structure. This report includes a new concept that reduces entropic loss using a quasicrystalline state and takes the first step in the development of new PCMs with significantly low phase-change energy and considerably high thermal stability. [ABSTRACT FROM AUTHOR]- Published
- 2020
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