Thermal-gradient-driven elemental segregation in Ge2Sb2Te5 phase change memory cells

doi:10.1063/1.5095470

This content will become publicly available on April 26, 2020

Title: Thermal-gradient-driven elemental segregation in Ge ₂Sb ₂Te ₅ phase change memory cells

Abstract

Thermal gradients have been predicted to play a large role in compositional segregation leading to failure in phase change memories. We have developed a methodology for isolating thermal-gradient driven segregation effects without interference from the electric field. In Ge ₂Sb ₂Te ₅ functional layers, Sb and Te move along the temperature gradient, while Ge segregates in the opposite direction. The direction of segregation is consistent for devices that were repeatedly melted, as well as for devices that were never melted and remained in the polycrystalline state. Here, the results have implications for the reliability of phase change memories.

Authors:

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Carnegie Mellon Univ., Pittsburgh, PA (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:: 2019-04-26

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

OSTI Identifier:: 1531245

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Applied Physics Letters

Additional Journal Information:: Journal Volume: 114; Journal Issue: 16; Journal ID: ISSN 0003-6951

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats


                    Yeoh, Phoebe, Ma, Yuanzhi, Cullen, David A., Bain, James A., and Skowronski, Marek. Thermal-gradient-driven elemental segregation in Ge2Sb2Te5 phase change memory cells.  United States: N. p., 2019. 
        Web.  doi:10.1063/1.5095470.

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                    Yeoh, Phoebe, Ma, Yuanzhi, Cullen, David A., Bain, James A., & Skowronski, Marek. Thermal-gradient-driven elemental segregation in Ge2Sb2Te5 phase change memory cells.  United States.  doi:10.1063/1.5095470.

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                    Yeoh, Phoebe, Ma, Yuanzhi, Cullen, David A., Bain, James A., and Skowronski, Marek. Fri .  
        "Thermal-gradient-driven elemental segregation in Ge2Sb2Te5 phase change memory cells".  United States.  doi:10.1063/1.5095470.

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@article{osti_1531245,

  title        = {Thermal-gradient-driven elemental segregation in Ge2Sb2Te5 phase change memory cells},

  author       = {Yeoh, Phoebe and Ma, Yuanzhi and Cullen, David A. and Bain, James A. and Skowronski, Marek},

  abstractNote = {Thermal gradients have been predicted to play a large role in compositional segregation leading to failure in phase change memories. We have developed a methodology for isolating thermal-gradient driven segregation effects without interference from the electric field. In Ge2Sb2Te5 functional layers, Sb and Te move along the temperature gradient, while Ge segregates in the opposite direction. The direction of segregation is consistent for devices that were repeatedly melted, as well as for devices that were never melted and remained in the polycrystalline state. Here, the results have implications for the reliability of phase change memories.},

  doi          = {10.1063/1.5095470},

  journal      = {Applied Physics Letters},

  number       = 16,

  volume       = 114,

  place        = {United States},

  year         = {2019},

  month        = {4}

}

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Works referenced in this record:

Thermomechanical properties and mechanical stresses of Ge₂Sb₂Te₅ films in phase-change random access memory
journal, November 2008

Park, Il-Mok; Jung, Jung-Kyu; Ryu, Sang-Ouk
Thin Solid Films, Vol. 517, Issue 2, p. 848-852
DOI: 10.1016/j.tsf.2008.08.194

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This content will become publicly available on April 26, 2020

Title: Thermal-gradient-driven elemental segregation in Ge 2Sb 2Te 5 phase change memory cells

Abstract

Citation Formats

Thermomechanical properties and mechanical stresses of Ge2Sb2Te5 films in phase-change random access memory journal, November 2008

Title: Thermal-gradient-driven elemental segregation in Ge ₂Sb ₂Te ₅ phase change memory cells

Thermomechanical properties and mechanical stresses of Ge₂Sb₂Te₅ films in phase-change random access memory
journal, November 2008