摘要
目的为了实现金刚石与GaN的良好键合,利用Ti/Ag中间层,在室温下开展了多晶金刚石与GaN的键合技术研究。方法首先,分别在抛光自支撑多晶金刚石晶圆以及GaN晶圆表面,通过磁控溅射依次沉积Ti黏附层、Ti/Ag梯度层以及纳米Ag层,形成Ti/Ag过渡层复合结构。然后通过真空键合系统成功实现了金刚石与Ga N键合。通过扫描电子显微镜(SEM)、原子力显微镜(AFM)、X射线衍射(XRD)以及X射线光电子能谱(XPS)等表征手段,对键合前后样品表面进行形貌及结构分析;通过超声扫描显微镜(SAM),以及拉伸力学测试系统,对键合后的键合率以及键合强度进行评价。结果借助Ti/Ag中间层进行键合,对晶圆表面的粗糙度具有较高容忍度,且在常温下即能实现良好键合,室温键合率达到95.5%。通过拉伸强度测试可知,键合强度达到13.7MPa。结论Ag纳米颗粒高的表面活性是实现键合界面常温融合的关键,而Ti底层良好的附着特性,Ti/Ag梯度层的引入以及Ti与Ag之间通过扩散反应形成的金属间化合物,则是提高金刚石与GaN键合强度的关键因素。
Wafer bonding has become the mainstream technology for developing GaN-on-Diamond devices.Room temperature bonding technology can avoid lattice mismatch and differences in thermal expansion coefficients caused by high temperature growth process,and there is no need to consider the low thermal conductivity of the nucleation layer.The use of diamond with high thermal conductivity as a bonding material can maximize the heat dissipation capacity.Therefore,the work aims to study the bonding technology between polycrystalline diamond and GaN with Ti/Ag intermediate layer at room temperature.Firstly,5 mm×5 mm diamond and GaN samples were ultrasonically cleaned.Afterwards,Ti adhesion layer,Ti/Ag gradient layer,and Ag nano-layer were deposited on the surface of polished free-standing polycrystalline diamond wafers and GaN wafers by magnetron sputtering,forming a Ti/Ag transition layer composite structure.The thickness of each layer was about 5 nm,with a total thickness of 5 nm.The Ti/Ag gradient layer with component transition was formed by controlling the deposition power.Finally,the deposited film sides of the two samples were attached and fixed,and diamond and GaN were successfully bonded through a vacuum bonding system at room temperature and certain pressure conditions.By means of scanning electron microscope(SEM),atomic force microscope(AFM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS),the morphology and structure of the sample surface were analyzed.The bonding rate and strength after bonding were evaluated with scanning acoustic microscope(SAM)and tensile mechanical testing system.With the help of Ti/Ag intermediate layer,good bonding between diamond and GaN was successfully achieved at room temperature.The use of metal film as the intermediate bonding layer had a high tolerance for the roughness of the wafer surface,and good bonding could be achieved at room temperature through diffusion,with a bonding rate of 95.5%at room temperature.Through tensile strength testing,the bonding strength reache
作者
乔冠中
李淑同
王越
刘金龙
陈良贤
魏俊俊
李成明
QIAO Guanzhong;LI Shutong;WANG Yue;LIU Jinlong;CHEN Liangxian;WEI Junjun;LI Chengming(Institute of Advanced Materials and Technology,University of Science and Technology Beijing,Beijing 100083,China;Shunde Innovation School,University of Science and Technology Beijing,Guangdong Foshan 528399,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2024年第18期175-182,共8页
Surface Technology
基金
国家自然科学基金(52172037)
北京市自然科学基金(2212036)
佛山市科技创新专项(BK21BE004)。
