Skip to main content
eScholarship
Open Access Publications from the University of California

UC Davis

UC Davis Previously Published Works bannerUC Davis

Tuning thermal transport in ultrathin silicon membranes by surface nanoscale engineering.

  • Author(s): Neogi, Sanghamitra
  • Reparaz, J Sebastian
  • Pereira, Luiz Felipe C
  • Graczykowski, Bartlomiej
  • Wagner, Markus R
  • Sledzinska, Marianna
  • Shchepetov, Andrey
  • Prunnila, Mika
  • Ahopelto, Jouni
  • Sotomayor-Torres, Clivia M
  • Donadio, Davide
  • et al.

Published Web Location

https://pubs.acs.org/doi/pdf/10.1021/nn506792d
No data is associated with this publication.
Abstract

A detailed understanding of the connections of fabrication and processing to structural and thermal properties of low-dimensional nanostructures is essential to design materials and devices for phononics, nanoscale thermal management, and thermoelectric applications. Silicon provides an ideal platform to study the relations between structure and heat transport since its thermal conductivity can be tuned over 2 orders of magnitude by nanostructuring. Combining realistic atomistic modeling and experiments, we unravel the origin of the thermal conductivity reduction in ultrathin suspended silicon membranes, down to a thickness of 4 nm. Heat transport is mostly controlled by surface scattering: rough layers of native oxide at surfaces limit the mean free path of thermal phonons below 100 nm. Removing the oxide layers by chemical processing allows us to tune the thermal conductivity over 1 order of magnitude. Our results guide materials design for future phononic applications, setting the length scale at which nanostructuring affects thermal phonons most effectively.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Item not freely available? Link broken?
Report a problem accessing this item