Band offsets between SiO{sub 2} and phase change materials in the (GeTe){sub x}(Sb{sub 2}Te{sub 3}){sub 1-x} pseudobinary system

Journal Article · Mon Mar 28 04:00:00 EDT 2011 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3573787· OSTI ID:21518357

Fang, Lina Wei-Wei; Yeo, Yee-Chia ^[1]; Rong, Zhao; Luping, Shi ^[2]; Zheng, Zhang; Jisheng, Pan ^[3]; Chong, Tow-Chong ^[4]

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1. Department of Electrical and Computer Engineering, National University of Singapore, Singapore 119260 (Singapore)
2. Data Storage Institute, Agency for Science, Technology and Research (A-STAR), DSI Building, 5 Engineering Drive 1, Singapore 117608 (Singapore)
3. Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A-STAR), 3 Research Link, Singapore 117602 (Singapore)
4. Singapore University of Technology and Design, 287 Ghim Moh Road 04-00, Singapore 279623 (Singapore)

The energy band alignment between stoichiometric phase change alloys residing along the pseudobinary line of GeTe-Sb{sub 2}Te{sub 3}[(GeTe){sub x}(Sb{sub 2}Te{sub 3}){sub 1-x}] and SiO{sub 2} was obtained employing high-resolution x-ray photoelectron spectroscopy. The valence band offsets were determined using both the core-level spectra and valence band spectra in the analysis. The results obtained show that the band offsets vary with the composition of the (GeTe){sub x}(Sb{sub 2}Te{sub 3}){sub 1-x} alloy, exhibiting a parabolic dependence on the amount of GeTe in the alloy. Increasing the proportion of GeTe in the (GeTe){sub x}(Sb{sub 2}Te{sub 3}){sub 1-x} alloy was generally found to increase (decrease) the valence band (conduction band) offsets, while the binary alloys (GeTe, Sb{sub 2}Te{sub 3}) have similar band offset values. This information could be useful for phase change memory device design and optimization.

• OSTI ID: 21518357
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 13 Vol. 98; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOY SYSTEMS
ANTIMONY COMPOUNDS
ANTIMONY TELLURIDES
BINARY ALLOY SYSTEMS
CHALCOGENIDES
DESIGN
ELECTRON SPECTROSCOPY
GERMANIUM COMPOUNDS
GERMANIUM TELLURIDES
GLASS
MATERIALS
MEMORY DEVICES
OXIDES
OXYGEN COMPOUNDS
PHASE CHANGE MATERIALS
PHASE TRANSFORMATIONS
PHOTOELECTRON SPECTROSCOPY
RESOLUTION
SILICON COMPOUNDS
SILICON OXIDES
SPECTRA
SPECTROSCOPY
STOICHIOMETRY
TELLURIDES
TELLURIUM COMPOUNDS
VALENCE
X-RAY PHOTOELECTRON SPECTROSCOPY