【作者】 张卓；

【导师】 汪学方；

【作者基本信息】 华中科技大学 ， 机械制造及其自动化， 2011， 硕士

【摘要】 微机电系统(Micro Electro Mechanical System, MEMS)是将微机械元件、微型传感器、微型执行器、信号处理与控制电路等集成于一体的微系统。很多MEMS器件,如陀螺仪、加速度传感器和谐振器等都需要采用真空封装来降低机械运动部件运动时气体的阻尼,提高器件的品质因数,从而提高器件的性能。目前国内外MEMS真空封装技术仍然不是非常成熟,还存在高成本、低可靠性等问题。因此MEMS真空封装是一个急需重点研究的课题。硅通孔(Through Silicon Via, TSV)技术是一种应用于高密度三维封装中的新兴互连技术。本文提出了一种MEMS真空封装的结构和工艺,根据MEMS圆片级真空封装的要求和TSV技术的特点,将TSV技术应用于MEMS圆片级真空封装中。研究的主要内容和创新点如下:(1)将TSV技术运用于MEMS圆片级真空封装中;(2)研究中比较几种圆片键合工艺的特点,结合项目要求,完成了金硅键合方案拟定、结构设计、工艺流程的设计以及掩膜版图形设计等设计工作;并完成工艺的制作,包括光刻、键合腔体的腐蚀以及键合工艺,并通过多次试验优化键合工艺参数;(3)研究TSV技术的特点,根据MEMS圆片级真空封装的特殊性和要求完成适用于MEMS圆片级真空封装的TSV的工艺的设计,并完成TSV工艺的制作,包括通孔刻蚀、绝缘层的制作、金属薄膜沉积和电镀填充等,最后通过多次试验优化工艺参数;(4)针对封装腔体内部的真空度变化和实时检测的问题,提出薄膜热敏电阻即皮拉尼计的方案,通过设计与计算得到皮拉尼计关键结构尺寸,完成皮拉尼计的加工,最后对皮拉尼计的特性进行了实验研究。(5)对本文中完成的封装进行检测和评价。包括粗检漏和细检漏两种不同的泄漏率的检测和键合强度的检测。更多还原

【Abstract】 MEMS (Micro Electro Mechanical System) is a micro system that integrate micro mechanical element, micro sensor, micro actuator and signal processing&control circuit. Many MEMS devices, like accelerometer, gyroscope and resonator, need vacuum packaging in order to reduce the damping of mechanical part moving, improve quality factor and increase property of device as well. However, development in MEMS vacuum packaging at home and abroad is not mature. So MEMS vacuum packaging is a project that in dire need to be researched on. TSV (Through Silicon Via) is a new interconnected technology that used in high density 3-dimensional packaging. A new structure and technique of MEMS vacuum packaging is proposed. TSV technique is used in MEMS wafer level vacuum packaging based on the need of wafer level vacuum packaging and characteristics of TSV. The detailed contents for this article are as follows:(1) TSV technology used in MEMS wafer level vacuum packaging is proposed.(2) According to the project need, the characteristics of several wafer bonding processes are compared. The structural design, process design and mask pattern design of Au-Si bonding scheme are completed. The processes of lithography, cavity etching and Au-Si bonding are completed as well. The Au-Si boding process parameters are optimized by multiple tests.(3) The characteristic of TSV is researched. TSV process design is completed based on the need and particularity of MEMS wafer level vacuum packaging. The processes of TSV technique including through-hole etching, insulating layer manufacture, metal film deposition and electroplating filling are completed as well, and the electroplating filling process parameters are optimized by multiple tests.(4) A scheme using film resistor (pirani gage) is propounded to resolve the problem of vacuum changes inside package and real Time monitoring. The dimension of pirani gage is received by structural design and calculation. Pirani gage manufacture and the research on characteristics of pirani gage are completed.(5) The vacuum packaging quality of this article are tested and evaluated, including leakage rate test (including rough test and accurate test) and bonding strength test.更多还原