基于纳米点嵌入的界面导热性能优化  

Nanodot embedding based optimization ofinterfacial thermal conductance

作　　者：邱钰珺 李亨宣 李亚涛 黄春朴 李卫华 张旭涛[1] 刘英光 Qiu Yu-Jun;Li Heng-Xuan;Li Ya-Tao;Huang Chun-Pu;Li Wei-Hua;Zhang Xu-Tao;Liu Ying-Guang(Department of Power Engineering,North China Electric Power University,Baoding 071003,China)

机构地区：[1]华北电力大学动力工程系,保定071003

出　　处：《物理学报》2023年第11期191-196,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:52076080);河北省自然科学基金(批准号:E2020502011)资助的课题.

摘　　要：调节界面热导(ITC)是纳米电子器件热管理的关键任务.本文采用非平衡态分子动力学方法研究了在界面处嵌入锡(Sn)纳米点对硅锗(Si/Ge)ITC的影响.研究发现,在声子弹性和非弹性两种竞争机制下ITC随Sn纳米点的数量的增加先升后降,在嵌入4个Sn纳米点时达到顶峰,ITC是完美界面(无纳米点嵌入)时的1.92倍.通过计算声子透射函数和态密度可以知道,ITC增加的原因是声子的非弹性散射得到加强,增强的非弹性声子散射为界面声子输运打开了新的通道.随着纳米点数量增加到一定值时,声子的弹性散射逐渐占据主导地位,ITC开始降低.Regulating the interfacial thermal conductance is a key task in the thermal management of electronic devices,and implanting nanostructures at the interface is an effective way to improve the interfacial thermal conductance.In order to study the effect of the embedding of nanostructures on the thermal conductivity of the interface,the effect of embedding tin(Sn)nanodots at the interface on the interfacial thermal conductance of silicon-germanium(Si/Ge)composite material is investigated by using a non-equilibrium molecular dynamics simulation.It is found that the phonon transmission function of the hybrid interface with embedded nanodots is significantly larger than that of the perfect interface(there are no nanodots at interface).The enhanced transmission function plays a role in facilitating the thermal transport at the interface,which enhances the interfacial thermal conductance.The simulation results also indicate that the interfacial thermal conductance changes nonlinearly with the increase of the number of Sn nanodots,firstincreasing and then decreasing.This is attributed to the competition between two phonon transport mechanisms,which are elastic scattering of phonons and inelastic scattering of phonons.When four nanodots are inserted,the interfacial thermal conductance reaches a maximum value,which is 1.92 times that of a perfect interface.In order to reveal the reason why the interfacial thermal conductance varies nonlinearly with the number of nanodots,the transmission function and density of states of photons are calculated,and the result indicates that the increasing of interfacial thermal conductance is due to the enhancement of phonons inelastic scattering,which opens new channels for the interfacial phonons transport.As the number of nanodots increases to a certain value,the elastic scattering of phonons gradually dominates,and the interfacial thermal conductance starts to decrease.In addition,temperature is also a key factor affecting the interfacial thermal conductance.This study shows that as the

关 键 词：界面热导 纳米点 分子动力学模拟 声子 

分 类 号：TB383.1[一般工业技术—材料科学与工程] O643.1[理学—物理化学]