东南大学学报（自然科学版）2017，Vol.47Issue(3)：490-494,5.DOI:10.3969/j.issn.1001-0505.2017.03.013
掺杂硅纳米薄膜法向热导率的分子动力学模拟
Molecular dynamics simulation of out-of-plane thermal conductivity of doped silicon nanofilms
摘要
Abstract
The out-of-plane thermal conductivities of both pure silicon nanofilm and that doped with germanium (Ge) with film thicknesses ranging from 2.2 to 104.4 nm were calculated by non-equilibrium molecular dynamics (NEMD) simulation at an average temperature of 300 K.Ge atoms were doped in a random pattern with a doping density of 5％ and 50％,respectively.The results show that there is a large reduction in thermal conductivities of the silicon nanofilm after doping with the same thickness.The out-of-plane thermal conductivity of the Ge-doping silicon nanofilm as well as that of a pure one increases with the increase of the film thickness.By calculating the thermal conductivity accumulation function in terms of phonon mean free path (MFP),it indicates that at 300 K the dominant contribution to the bulk thermal conductivity of pure silicon comes from phonons with MFPs between 2 and 2 000 nm,while the MFPs of phonons that contribute about 80％ to the bulk thermal conductivity of Ge-doping silicon are between 0.1 and 30 nm,thus they are much less than those of the pure silicon.关键词
硅纳米薄膜/热导率/掺杂/分子动力学/声子平均自由程/热导率累积函数Key words
silicon nanofilm/thermal conductivity/doping/molecular dynamics/phonon mean free path/thermal conductivity accumulation function分类
能源科技引用本文复制引用
陈慧,魏志勇,陈伟宇,刘晨晗,毕可东,陈云飞..掺杂硅纳米薄膜法向热导率的分子动力学模拟[J].东南大学学报（自然科学版）,2017,47(3):490-494,5.基金项目
国家自然科学基金资助项目(51205061,51375092). （51205061,51375092）
