Molecular dynamics simulation of film size and vacancy defect effects on the thermal conductivities of argon thin films

Abstract

It is well known that there is a size effect for the thermal conductivity of thin films and that vacancy defects in film reduce the film's thermal conduction. In this paper, the film size and vacancy defect effects on the thermal conductivities of argon thin films were studied by molecular dynamics simulations. The results show the existence of phonon boundary scattering. The results also confirm that the theoretical model based on the Boltzmann equation can accurately model the thermal conduction of thin argon films. Both the theoretical and MD results illustrate that, although, both the defect and the thickness of the thin film deduce the thermal conductivity, their physical mechanisms differ.

Keywords:

• molecular dynamics simulation
• size effect
• vacancy
• thermal conductivity

Acknowledgements

The project was supported by the National Natural Science Foundation of China (No. 50676047) and the Tsinghua Basic Research Foundation (No. JCpy2005049).