Thermal boundary resistance at Si/Ge interfaces by molecular dynamics simulation

Tianzhuo Zhan, Satoshi Minamoto, Yibin Xu, Yoshihisa Tanaka, Yutaka Kagawa

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

In this study, we investigated the temperature dependence and size effect of the thermal boundary resistance at Si/Ge interfaces by non-equilibrium molecular dynamics (MD) simulations using the direct method with the Stillinger-Weber potential. The simulations were performed at four temperatures for two simulation cells of different sizes. The resulting thermal boundary resistance decreased with increasing temperature. The thermal boundary resistance was smaller for the large cell than for the small cell. Furthermore, the MD-predicted values were lower than the diffusion mismatch model (DMM)-predicted values. The phonon density of states (DOS) was calculated for all the cases to examine the underlying nature of the temperature dependence and size effect of thermal boundary resistance. We found that the phonon DOS was modified in the interface regions. The phonon DOS better matched between Si and Ge in the interface region than in the bulk region. Furthermore, in interface Si, the population of low-frequency phonons was found to increase with increasing temperature and cell size. We suggest that the increasing population of low-frequency phonons increased the phonon transmission coefficient at the interface, leading to the temperature dependence and size effect on thermal boundary resistance.

Original languageEnglish
Article number047102
JournalAIP Advances
Volume5
Issue number4
DOIs
Publication statusPublished - 2015 Apr 1
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Thermal boundary resistance at Si/Ge interfaces by molecular dynamics simulation'. Together they form a unique fingerprint.

  • Cite this