Abstract
Despite extensive studies on thermal transport in thin silicon films, there has been little work studying the thermal conductivity of single-crystal rectangular, cross-sectional nanobeams that are commonly used in many applications such as nanoelectronics (FinFETs), nano-electromechanical systems, and nanophotonics. Here, we report experimental data on the thermal conductivity of silicon nanobeams of a thickness of ∼78 nm and widths of ∼65 nm, 170 nm, 270 nm, 470 nm, and 970 nm. The experimental data agree well (within ∼9%) with the predictions of a thermal conductivity model that uses a combination of bulk mean free paths obtained from ab initio calculations and a suppression function derived from the kinetic theory. This work quantifies the impact of nanobeam aspect ratios on thermal transport and establishes a criterion to differentiate between thin films and beams in studying thermal transport. The thermal conductivity of a 78 nm × 65 nm nanobeam is ∼32 W m-1 K-1, which is roughly a factor of two smaller than that of a 78 nm thick film.
Original language | English |
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Article number | 213102 |
Journal | Applied Physics Letters |
Volume | 110 |
Issue number | 21 |
DOIs | |
Publication status | Published - 2017 May 22 |
Externally published | Yes |
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)