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Title: Thermal conductivity measurement of amorphous dielectric multilayers for phase-change memory power reduction

Abstract

In this work, we investigate the temperature-dependent thermal conductivities of few nanometer thick alternating stacks of amorphous dielectrics, specifically SiO{sub 2}/Al{sub 2}O{sub 3} and SiO{sub 2}/Si{sub 3}N{sub 4}. Experiments using steady-state Joule-heating and electrical thermometry, while using a micro-miniature refrigerator over a wide temperature range (100–500 K), show that amorphous thin-film multilayer SiO{sub 2}/Si{sub 3}N{sub 4} and SiO{sub 2}/Al{sub 2}O{sub 3} exhibit through-plane room temperature effective thermal conductivities of about 1.14 and 0.48 W/(m × K), respectively. In the case of SiO{sub 2}/Al{sub 2}O{sub 3}, the reduced conductivity is attributed to lowered film density (7.03 → 5.44 × 10{sup 28 }m{sup –3} for SiO{sub 2} and 10.2 → 8.27 × 10{sup 28 }m{sup –3} for Al{sub 2}O{sub 3}) caused by atomic layer deposition of thin-films as well as a small, finite, and repeating thermal boundary resistance (TBR) of 1.5 m{sup 2} K/GW between dielectric layers. Molecular dynamics simulations reveal that vibrational mismatch between amorphous oxide layers is small, and that the TBR between layers is largely due to imperfect interfaces. Finally, the impact of using this multilayer dielectric in a dash-type phase-change memory device is studied using finite-element simulations.

Authors:
;  [1];  [2];  [3];  [4]; ;  [5]; ;  [6]
  1. Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)
  2. Department of Material Science and Engineering, Stanford University, Stanford, California 94305 (United States)
  3. (United States)
  4. School of Energy and Power Engineering, Xi'an Jiatong University, Xi'an, Shaanxi 710049 (China)
  5. Hewlett-Packard Labs, 1501 Page Mill Rd., Palo Alto, California 94304 (United States)
  6. Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States)
Publication Date:
OSTI Identifier:
22597851
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; DENSITY; DIELECTRIC MATERIALS; FINITE ELEMENT METHOD; JOULE HEATING; LAYERS; MEMORY DEVICES; MOLECULAR DYNAMICS METHOD; SILICA; SILICON NITRIDES; SILICON OXIDES; SIMULATION; STEADY-STATE CONDITIONS; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0273-0400 K; THERMAL BOUNDARY RESISTANCE; THERMAL CONDUCTIVITY; THIN FILMS

Citation Formats

Fong, S. W., E-mail: swfong@stanford.edu, Wong, H.-S. P., Sood, A., Department of Mechanical Engineering, Stanford University, Stanford, California 94305, Chen, L., Kumari, N., Gibson, G. A., Asheghi, M., and Goodson, K. E. Thermal conductivity measurement of amorphous dielectric multilayers for phase-change memory power reduction. United States: N. p., 2016. Web. doi:10.1063/1.4955165.
Fong, S. W., E-mail: swfong@stanford.edu, Wong, H.-S. P., Sood, A., Department of Mechanical Engineering, Stanford University, Stanford, California 94305, Chen, L., Kumari, N., Gibson, G. A., Asheghi, M., & Goodson, K. E. Thermal conductivity measurement of amorphous dielectric multilayers for phase-change memory power reduction. United States. doi:10.1063/1.4955165.
Fong, S. W., E-mail: swfong@stanford.edu, Wong, H.-S. P., Sood, A., Department of Mechanical Engineering, Stanford University, Stanford, California 94305, Chen, L., Kumari, N., Gibson, G. A., Asheghi, M., and Goodson, K. E. 2016. "Thermal conductivity measurement of amorphous dielectric multilayers for phase-change memory power reduction". United States. doi:10.1063/1.4955165.
@article{osti_22597851,
title = {Thermal conductivity measurement of amorphous dielectric multilayers for phase-change memory power reduction},
author = {Fong, S. W., E-mail: swfong@stanford.edu and Wong, H.-S. P. and Sood, A. and Department of Mechanical Engineering, Stanford University, Stanford, California 94305 and Chen, L. and Kumari, N. and Gibson, G. A. and Asheghi, M. and Goodson, K. E.},
abstractNote = {In this work, we investigate the temperature-dependent thermal conductivities of few nanometer thick alternating stacks of amorphous dielectrics, specifically SiO{sub 2}/Al{sub 2}O{sub 3} and SiO{sub 2}/Si{sub 3}N{sub 4}. Experiments using steady-state Joule-heating and electrical thermometry, while using a micro-miniature refrigerator over a wide temperature range (100–500 K), show that amorphous thin-film multilayer SiO{sub 2}/Si{sub 3}N{sub 4} and SiO{sub 2}/Al{sub 2}O{sub 3} exhibit through-plane room temperature effective thermal conductivities of about 1.14 and 0.48 W/(m × K), respectively. In the case of SiO{sub 2}/Al{sub 2}O{sub 3}, the reduced conductivity is attributed to lowered film density (7.03 → 5.44 × 10{sup 28 }m{sup –3} for SiO{sub 2} and 10.2 → 8.27 × 10{sup 28 }m{sup –3} for Al{sub 2}O{sub 3}) caused by atomic layer deposition of thin-films as well as a small, finite, and repeating thermal boundary resistance (TBR) of 1.5 m{sup 2} K/GW between dielectric layers. Molecular dynamics simulations reveal that vibrational mismatch between amorphous oxide layers is small, and that the TBR between layers is largely due to imperfect interfaces. Finally, the impact of using this multilayer dielectric in a dash-type phase-change memory device is studied using finite-element simulations.},
doi = {10.1063/1.4955165},
journal = {Journal of Applied Physics},
number = 1,
volume = 120,
place = {United States},
year = 2016,
month = 7
}
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