Thermal conductivity of Si{endash}Ge superlattices
- Department of Materials Science and Engineering
- Center for Semiconductor Research, Research Triangle Institute, Research Triangle Park, Durham, North Carolina 27709-2195 (United States)
The thermal conductivity of Si{endash}Ge superlattices with superlattice periods 30{lt}L{lt}300 {Angstrom}, and a Si{sub 0.85}Ge{sub 0.15} thin film alloy is measured using the 3{omega} method. The alloy film shows a conductivity comparable to bulk SiGe alloys while the superlattice samples have a thermal conductivity that is smaller than the alloy. For 30{lt}L{lt}70 {Angstrom}, the thermal conductivity decreases with decreasing L; these data provide a lower limit to the interface thermal conductance G of epitaxial Si{endash}Ge interfaces: G{gt}2{times}10{sup 9}Wm{sup {minus}2}K{sup {minus}1} at 200 K. Superlattices with relatively longer periods, L{gt}130 {Angstrom}, have smaller thermal conductivities than the short-period samples. This unexpected result is attributed to a strong disruption of the lattice vibrations by extended defects produced during lattice-mismatched growth. {copyright} {ital 1997 American Institute of Physics.}
- Research Organization:
- Univ. of Illinois at Urbana-Champaign, IL (United States)
- DOE Contract Number:
- FG02-91ER45439
- OSTI ID:
- 508920
- Journal Information:
- Applied Physics Letters, Vol. 70, Issue 22; Other Information: PBD: Jun 1997
- Country of Publication:
- United States
- Language:
- English
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