Au/Sn共晶键合技术在MEMS封装中的应用  

Application of the Au/Sn Eutectic Bonding Technology in the Packaging of MEMS

作　　者：胥超[1] 徐永青[1] 杨拥军[1] 杨志[2] 

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050051 [2]专用集成电路重点实验室,石家庄050051

出　　处：《微纳电子技术》2014年第2期131-135,共5页Micronanoelectronic Technology

摘　　要：研究了Au/Sn共晶圆片键合技术在MEMS气密性封装中的应用。设计了共晶键合多层材料的结构和密封环图形,盖帽层采用Ti/Ni/Au/Sn/Au结构,器件层采用Ti/Ni/Au结构,盖帽层腔体尺寸为4.5 mm×4.5 mm×20μm,Au/Sn环的宽度为700μm,优化了键合工艺,对影响气密性的因素(如组分配比、键合前处理和键合温度等)进行了分析。两层硅片在氮气气氛中靠静态的压力实现紧密接触。在峰值温度为300℃、持续时间为2 min的条件下实现了良好的键合效果,其剪切力平均值达到16.663 kg,漏率小于2×10-3 Pa·cm3/s,满足检验标准(GJB548A)的要求,验证了Au/Sn共晶键合技术在MEMS气密封装中的适用性。Abstract： The application of Au/Sn eutectic wafer bonding technology was researched in the her- metic packaging technology for MEMS. The structures of the eutectic bonding multi-layer mate- rials and the pattern of sealing rings were designed. The metal structure of the cap layer is Ti/ Ni/Au/Sn/Au, and the bottom layer structure is Ti/Ni/Au. The cavity size of the cap layer is 4. 5 mm - 4.5 mm x 20μm, and the Au/Sn sealing ring width is 700 μm. The bonding process was optimized, and the key factors （such as the composition ratio, bonding pretreatment and bonding temperature） affecting the airtightness of the hermetic packaging were analyzed. Two layers of silicon wafers were closely contacted by the static pressure in the nitrogen atmosphere. The good bonding was realized at the peak temperature of 300 ℃C for the duration time of 2 min. The average value of the high shear strength reaches 16. 663 kg and the leak rate is less than 2 x 10-3 Pa ℃ cm3/s, meeting the requirements of the inspection standard （GJB548A）. The applicability of the Au/Sn eutectic bonding technology was verified in the hermetic packaging technology for MEMS.

关 键 词：圆片级键合 键合温度 前处理 应力 剪切强度 漏率 

分 类 号：TH703[机械工程—仪器科学与技术] TN305.94[机械工程—精密仪器及机械]