Thermally conductive ultra-low-k dielectric layers based on two-dimensional covalent organic frameworks

Austin M. Evans, Ashutosh Giri, Vinod K. Sangwan, Sangni Xun, Matthew Bartnof, Carlos G. Torres-Castanedo, Halleh B. Balch, Matthew S. Rahn, Nathan P. Bradshaw, Edon Vitaku, David W. Burke, Hong Li, Michael J. Bedzyk, Feng Wang, Jean Luc Brédas, Jonathan A. Malen, Alan J.H. McGaughey, Mark C. Hersam, William R. Dichtel, Patrick E. Hopkins

Research output: Contribution to journalArticlepeer-review

168 Scopus citations


As the features of microprocessors are miniaturized, low-dielectric-constant (low-k) materials are necessary to limit electronic crosstalk, charge build-up, and signal propagation delay. However, all known low-k dielectrics exhibit low thermal conductivities, which complicate heat dissipation in high-power-density chips. Two-dimensional (2D) covalent organic frameworks (COFs) combine immense permanent porosities, which lead to low dielectric permittivities, and periodic layered structures, which grant relatively high thermal conductivities. However, conventional synthetic routes produce 2D COFs that are unsuitable for the evaluation of these properties and integration into devices. Here, we report the fabrication of high-quality COF thin films, which enable thermoreflectance and impedance spectroscopy measurements. These measurements reveal that 2D COFs have high thermal conductivities (1 W m−1 K−1) with ultra-low dielectric permittivities (k = 1.6). These results show that oriented, layered 2D polymers are promising next-generation dielectric layers and that these molecularly precise materials offer tunable combinations of useful properties.

Original languageEnglish (US)
Pages (from-to)1142-1148
Number of pages7
JournalNature materials
Issue number8
StatePublished - Aug 2021

ASJC Scopus subject areas

  • General Chemistry
  • General Materials Science
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

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