碳化硅直接键合机理及其力学性能研究

随着碳化硅(SiC)材料的MEMS器件在恶劣环境测量中的应用前景和迫切需求,进行了碳化硅的直接键合实验.研究了工艺条件对键合样品力学性能的影响,同时借助激光共聚焦扫描显微镜(CLSM)、扫描电子显微镜(SEM)、能谱仪(EDS)和拉曼光谱仪等对碳化硅键合样品界面的微观结构进行了分析.结果表明:退火温度和加载压力是影响键合效果的关键性因素.当退火温度为1 300℃,加载压力为3 MPa和退火时间为3 h时,此时键合样品的气密性非常好,力学性能达到最佳,键合强度2 MPa.最后通过样品微观界面分析表明碳化硅直接键合的机理为界面氧化硅过渡层的形成及粘性流动与碳化硅和碳化硅的熔融直接键合.

Mechanisms and Mechanical Properties of the Interface between SiC and SiC by Direct Bonding

For the broad prospect and imminence requirement of silicon carbide(SiC)material MEMS devices in harsh environments,direct bonding between SiC and SiC was achieved. The influence of the bonding process on the mechanical properties of bonded samples was investigated and optimized,and the bonding interfaces of the bonded sample were analyzed by confocal laser scanning microscope(CLSM),scanning electron microscopy(SEM),energy dispersive spectrometer(EDS)and Raman spectroscopy,respectively.The results indicate that the annealing temper-ature and the loading force are the main factors of the formation of the bonded samples. At the condition of anneal-ing temperature=1 300℃,loading force=3 MPa,and annealing time=3 h,air tightness of the bonded sample is ex-cellent,and it has the best mechanical property. Its bonding strength reaches 2 MPa. A transition layer between the bonding interface at the high temperature,which can appears viscous flow,and SiC-SiC fusion direct bonding are the principles of direct bonding between SiC and SiC through the microscopic interface.