Abstract
By confining phase transitions to the nanoscale interface between two different crystals, interfacial phase change memory heterostructures represent the state of the art for energy efficient data storage. We present the effect of strain engineering on the electrical switching performance of the Sb2Te3– GeTe superlattice van der Waals devices. Multiple Ge atoms switching through a two-dimensional Te layer reduces the activation barrier for further atoms to switch; an effect that can be enhanced by biaxial strain. The out-of-plane phonon mode of the GeTe crystal remains active in the superlattice heterostructures. The large in-plane biaxial strain imposed by the Sb2Te3layers on the GeTe layers substantially improves the switching speed, reset energy, and cyclability of the superlattice memory devices. Moreover, carefully controlling residual stress in the layers of Sb2Te3–GeTe interfacial phase change memories provides a new degree of freedom to design the properties of functional superlattice structures for memory and photonics applications.
Original language | English |
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Article number | 025003 |
Journal | Nano Futures |
Volume | 1 |
Issue number | 2 |
DOIs |
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Publication status | Published - 1 Sept 2017 |
Bibliographical note
Funding Information:This work was supported by the SUTD-MIT International Design Centre (IDC), Designer Chalcogenides Project (IDCSF1200108OH) and the A-star Singapore–China joint research program under the grant 1420200046. SL, LW, and ZS acknowledge the support from the National Key Research and Development Program of China (2017YFB0701703) and the National Natural Science Foundation of China (61076121).We thank Dr Zefang Zhang for donating Raman sample substrates.
Publisher Copyright:
© 2017 IOP Publishing Ltd.
Keywords
- Avalanche effect
- Interfacial disordering
- Phase change memory
- Strain engineering
- Superlattice
ASJC Scopus subject areas
- Bioengineering
- General Chemistry
- Atomic and Molecular Physics, and Optics
- Biomedical Engineering
- General Materials Science
- Electrical and Electronic Engineering