Electrically Driven Reversible Phase Changes in Layered In2 Se3 Crystalline Film

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 29(2017), 42 vom: 19. Nov.
1. Verfasser: Choi, Min Sup (VerfasserIn)
Weitere Verfasser: Cheong, Byung-Ki, Ra, Chang Ho, Lee, Suyoun, Bae, Jee-Hwan, Lee, Sungwoo, Lee, Gun-Do, Yang, Cheol-Woong, Hone, James, Yoo, Won Jong
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2017
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article indium selenides layered materials metal-to-insulator transition phase changes vacancy layers
Beschreibung
Zusammenfassung:© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
An unconventional phase-change memory (PCM) made of In2 Se3 , which utilizes reversible phase changes between a low-resistance crystalline β phase and a high-resistance crystalline γ phase is reported for the first time. Using a PCM with a layered crystalline film exfoliated from In2 Se3 crystals on a graphene bottom electrode, it is shown that SET/RESET programmed states form via the formation/annihilation of periodic van der Waals' (vdW) gaps (i.e., virtual vacancy layers) in the stack of atomic layers and the concurrent reconfiguration of In and Se atoms across the layers. From density functional theory calculations, β and γ phases, characterized by octahedral bonding with vdW gaps and tetrahedral bonding without vdW gaps, respectively, are shown to have energy bandgap value of 0.78 and 1.86 eV, consistent with a metal-to-insulator transition accompanying the β-to-γ phase change. The monolithic In2 Se3 layered film reported here provides a novel means to achieving a PCM based on melting-free, low-entropy phase changes in contrast with the GeTe-Sb2 Te3 superlattice film adopted in interfacial phase-change memory
Beschreibung:Date Completed 18.07.2018
Date Revised 30.09.2020
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.201703568