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  • Open Access

Static dielectric constant of thin dielectrics in extremely scaled silicon nanosheet transistors

Massimo V. Fischetti1,*, Dallin O. Nielsen1, and Edward Chen2

  • *Contact author: max.fischetti@utdallas.edu
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APS Open Sci. 1, 000207 – Published 6 November, 2026

DOI: https://doi.org/10.1103/gx65-fjlr

Abstract

We argue that the static dielectric constant of small (thin and/or narrow) semiconductor and insulator nanostructures depends strongly on their environment. We do so by considering the electronic response, simply reviewing, briefly but critically, the existing literature. Regarding the ionic response, in addition to reviewing the literature, we use a simple model to account for the confinement of optical phonons in thin films and show that the reduction of their density of states has a negligible effect on the dielectric constant, in contrast to some claims found in the literature. In general, we argue that in realistic structures, such as double-gated Si nanosheets, the use of the bulk dielectric constants for both the channel and the gate insulators is justified.

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References (26)

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APS Open Sci. 1, 000207– Published 6 November, 2026
Vol. 1
  • Received 31 July 2026
  • Revised 30 September 2026
  • Accepted 27 October 2026
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