Thermal Conductivity of Amorphous and Crystalline SiO₂ Nano-Films from Molecular Dynamics Simulations

Abstract:

Normal thermal conductivity of amorphous and crystalline SiO₂ nano-films is calculated by nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 100 to 700K and thicknesses from 2 to 6nm. The calculated temperature and thickness dependences of thermal conductivity are in good agreement with previous literatures. In the same thickness, higher thermal conductivity is obtained for crystalline SiO₂ nano-films. And more importantly, for amorphous SiO₂ nano-films, thickness can be any direction of x, y, z-axis without effect on the normal thermal conductivity, for crystalline SiO₂ nano-films, the different thickness directions obtain different thermal conductivity results. The different results of amorphous and crystalline SiO₂ nano-films simply show that film thickness and grain morphology will cause different effects on thermal conductivity.

• Periodical: Key Engineering Materials (Volume 501)
• Pages: 64-69
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.501.64
• Online since: January 2012
• Authors: Yan He, Yuan Zheng Tang, Man Ding, Lian Xiang Ma
• Keywords: Amorphous SiO₂, Crystalline SiO₂, Molecular Dynamic (MD), Nano-Films, Thermal Conductivity (TC)

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