基于拉曼散射的石墨烯/氧化硅界面传热研究  

Thermal Transport Study of Graphene/SiO_2 Interface Based on Two-Step Raman Thermometry

作　　者：李满[1] 赵晓龙[2] 肖湘衡[2] 岳亚楠[1] 

机构地区：[1]武汉大学动力与机械学院,武汉430072 [2]武汉大学物理科学与技术学院,武汉430072

出　　处：《工程热物理学报》2016年第9期1945-1951,共7页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51206124;No.51428603)

摘　　要：本文提出了一种"拉曼热测量两步法",成功测量了单层石墨烯与二氧化硅基底之间的界面热阻和石墨烯在基底作用下的导热系数。第一步利用稳态电流加热石墨烯,利用拉曼响应测量其与基底的温差,继而测得石墨烯与基底之间的界面热阻。第二步通过激光加热,由拉曼散射信号获得不同加热功率下的石墨烯的局部温度,根据点热源热扩散模型推导出石墨烯的导热系数。研究发现非约束状态下的石墨烯在加热状态下由于具有明显的形貌变化(褶皱,局部脱离基底等),导致产生较大的接触热阻;同时实验发现由于界面处的声子散射和泄漏,基底状态下的石墨烯导热系数较低。本文利用拉曼热测量技术同时实现了石墨烯界面热阻和石墨烯导热系数的无损化和非接触式测量。In this work,we propose a two-step Raman method for comprehensively study thermal transport of graphene interface materials,and accomplish interface thermal resistance characterization and in-plane thermal conductivity measurement of graphene/Si02 Interface.The first step is to measure interfacial thermal resistance between graphene and substrate by probing temperature difference between them based on Raman thermometry when the graphene is uniformly heated.The second step is measuring the local temperature response of graphene by Raman thermometry applied with laser heating.Thermal conductivity of supported graphene can be calculated from the theory for two parallel transport directions：in-plane transport and interface transport.Results show that the thermal resistance between graphene and SiO_2 is 2.94^（＋1.90）_（-1.44）×10^（-3） m^2·K/W,which is attributed to the morphology change（corrugation and local separation of samples） caused by electrical heating Thermal conductivity of this supported graphene is significantly suppressed to 179^（＋111）_（-86） W/（m·K）.Phonons scattering and leakage at the interface are mainly responsible for the huge reduction of thermal conductivity of graphene on substrate.This two-step Raman approach simultaneously realizes the comprehensive study of interfacial thermal resistance and thermal conductivity of raw graphene interface materials.

关 键 词：拉曼散射 石墨烯 导热系数 界面热阻 

分 类 号：TK124[动力工程及工程热物理—工程热物理]