Measurements of the Thermal Resistivity of InAlAs, InGaAs, and InAlAs/InGaAs Superlattices

Journal Article · Tue Feb 26 00:00:00 EST 2019 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/acsami.8b17268· OSTI ID:1605418

Jaffe, G. R. ^[1]; Mei, S. ^[2]; Boyle, C. ^[2]; Kirch, J. D. ^[2]; Savage, D. E. ^[2]; Botez, D. ^[2]; Mawst, L. J. ^[2]; Knezevic, I. ^[2]; Lagally, M. G. ^[2]; Eriksson, M. A. ^[2]

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1. Univ. of Wisconsin, Madison, WI (United States); University of Wisconsin-Madison Department of Physics
2. Univ. of Wisconsin, Madison, WI (United States)

Thermal management efforts in nanoscale devices must consider both the thermal properties of the constituent materials and the interfaces connecting them. It is currently unclear whether alloy/alloy semiconductor superlattices such as InAlAs/InGaAs have lower thermal conductivities than their constituent alloys. We report measurements of the crossplane thermal resistivity of InAlAs/InGaAs superlattices at room temperature, showing that the superlattice resistivities are larger by a factor of 1.2–1.6 than that of the constituent bulk materials, depending on the strain state and composition. We show that the additional resistance present in these superlattices can be tuned by a factor of 2.5 by altering the lattice mismatch and thereby the phonon-mode mismatch at the interfaces, a principle that is commonly assumed for superlattices but has not been experimentally verified without adding new elements to the layers. We find that the additional resistance in superlattices does not increase significantly when the layer thickness is decreased from 4 to 2 nm. Here, we also report measurements of 250–1000 nm thick films of undoped InGaAs and InAlAs lattice-matched to InP substrates, for there is no published thermal conductivity value for the latter, and we find it to be 2.24 ± 0.09 at 22 °C, which is ~2.7 times smaller than the widely used estimates.

• Research Organization: Univ. of Wisconsin, Madison, WI (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: FG02-03ER46028; SC0008712
• OSTI ID: 1605418
• Journal Information: ACS Applied Materials and Interfaces, Journal Name: ACS Applied Materials and Interfaces Journal Issue: 12 Vol. 11; ISSN 1944-8244
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
InAlAs
InGaAs
Thermal conductivity
quantum cascade laser
superlattice
thermal resistivity