Effects of surface/interface stress on phonon properties and thermal conductivity in AlN/GaN/AlN heterostructural nanofilms

Siyang Zhang, Xiaoya Tang, Haihui Ruan, Linli Zhu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

4 Citations (Scopus)

Abstract

The effect of surface/interface stress on phonon properties and thermal conductivity of GaN-based heterostructural nanofilms was theoretically investigated through the involvement of stress-dependent elastic modulus of nanostructures. The elastic model was used to quantitatively describe the spatially confined phonons in a GaN-based nanofilm under surface/interface stresses. The relationship between surface/interface stress and phonon thermal conductivity was further calculated for different phonon modes. Numerical results show that the positive (negative) surface/interface stress increases (decreases) the phonon energy and phonon group velocity while decreases (increases) the phonon density of state. With the increase of surface/interface stress, the phonon thermal conductivity of a nanofilm increases in SH mode but decreases in AS and SA modes. The surface/interface stress can also alter the temperature dependence of phonon thermal conductivity in heterostructural nanofilms. These simulation results will contribute to the analysis of heat transport in GaN-based heterostructural nanostructures and provide the theoretical support for the thermal performance design and optimization in GaN-based electronic devices.

Original languageEnglish
Article number732
JournalApplied Physics A: Materials Science and Processing
Volume125
Issue number10
DOIs
Publication statusPublished - 1 Oct 2019

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)

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