摘要
为研究高功率氮化镓器件散热性能,构建氮化镓/石墨烯/金刚石异质结构,采用分子动力学方法调控异质界面热输运特性,并从声子输运角度揭示异质界面传热机理与调控机制.研究发现Ga-C接触方式的界面热导是N-C结构的3倍,且氮化镓/石墨烯/金刚石异质结构不具有热整流特性.N和B掺杂下界面热导先增大后减小,但Si掺杂下界面热导单调增大.两种Si掺杂势函数对应的界面热导差异不大,但双势函数下的石墨烯结构更稳定.线性掺杂和圆形掺杂两种掺杂形貌对界面热导影响不大,但线性掺杂下石墨烯声子谱变化更具规律性.氢化会严重阻碍界面传热,但三种氢化结构下的界面热导均随氢化率增加而增大.研究结果可为氮化镓器件热管理提供理论支持,同时对突破大功率电子器件散热瓶颈具有指导价值.
In order to ascertain the heat dissipation performance of high-power gallium nitride devices,the thermal transport characteristics of GaN/graphene/diamond heterostructures are investigated at heterogeneous interfaces through molecular dynamics simulations.This study focuses on phonon transport mechanisms and regulatory strategies in the interfacial regions.The key findings are summarized below.Comparative analysis of two contact configurations reveals that the Ga-C structure exhibits an interfacial thermal conductance three times higher than that of the N-C structure,which is attributed to its larger phonon cutoff frequency and enhanced interfacial phonon coupling as evidenced by phonon spectral analysis.The intrinsic heterostructure demonstrates no thermal rectification characteristics without interface engineering.The analysis of hydrogenation effects shows that although hydrogenation generally hinders interfacial heat transfer,the thermal conductance increases paradoxically with the increase of hydrogenation ratio.This counterintuitive phenomenon arises from hydrogen-induced lattice disorder/hybridization scattering causing phonon localization(particularly severe in GaN-side hydrogenation),while generating new phonon coupling channels.The elemental doping investigations show that nitrogen and boron doping leads to an initial increase and subsequent decrease in interfacial thermal conductance,while silicon doping produces monotonic enhancement.Overlap factor analysis indicates that N and B doping first strengthens then weakens interfacial phonon coupling,whereas Si doping significantly improves coupling through synergistic effects of strong interfacial interactions and phonon focusing.Comparative evaluation of two Si doping potential functions shows that the difference in thermal conductance results is negligible.The studies on doping morphology show that although linear doping configurations can cause systematic changes in graphene phonon spectra,their influence on interfacial thermal conductance is minimal.These findings offer critical theoretical insights into thermal management optimization of GaN-based devices and provide fundamental guidance for overcoming thermal dissipation bottlenecks in high-power electronic systems.
作者
刘东静
王鹏博
胡志亮
陆佳琪
肖煜
黄家强
LIU Dongjing;WANG Pengbo;HU Zhiliang;LU Jiaqi;XIAO Yu;HUANG Jiaqiang(Guangxi Education Department Key Laboratory of Microelectronic Packaging and Assembly Technology,College of Mechanical and Electrical Engineering,Guilin University of Electronic Technology,Guilin 541004,China;Guilin LDZX Semiconductor Co.,Ltd.,Guilin 541004,China)
出处
《物理学报》
北大核心
2025年第21期45-58,共14页
Acta Physica Sinica
基金
2024年度广西高校中青年教师科研基础能力提升项目(批准号:2024KY0203)
南宁市科学研究与技术开发计划科技重大专项(批准号:20241026)
广西重点研发计划(批准号:桂科AB25069315)
桂林电子科技大学研究生教育创新计划(批准号:2024YCXS016)
2023年广西壮族自治区级新工科研究与实践项目(批准号:XGK202309)资助的课题.
关键词
异质结构
分子动力学
界面热导
氢化
调控机理
heterostructure
molecular dynamics
interfacial thermal conductivity
hydrogenation
regulation mechanism
