SBIR Phase I: A Universal Wafer-Level Capping Process for MEMS and Microdevices

该小型企业创新研究(SBIR)第一阶段项目为微电子机械系统(MEMS)和其他微型设备提供通用封盖技术。这项技术将允许数千个移动的MEMS设备在惰性气体或真空中免受环境影响。CAP晶片技术本身已经开发完成--该项目的重点是开发广泛的焊料合金键合技术，以实现牢固的键合、良好的器件电气连接以及各种工艺和器件功能的几乎为零泄漏率的真空/密封密封。结合强度取决于金属沉积条件、连接前后的热平衡以及每种材料(金-铟、镍-锡、银-铟、银-锡、铜-铟等)之间的化学反应。电学特性将包括优化熔敷金属堆栈，以实现低电阻、欧姆接触的最佳化学电势和低电偶。最初，粘合的均匀性将通过检查来表征，但最终将通过密封/真空密封的传感器来表征，从而允许精细的泄漏率测量(10-15立方厘米/秒)和放气(原子从微腔表面解吸)的表征，以表征功能性密封/真空封装的成品率。该项目的更广泛的影响/商业潜力是为微电子机械系统(MEMS)提供通用的封装技术。封装(提供电气连接和环境保护)通常是将MEMS推向市场的最困难部分。MEMS市场预计将从2008年的80亿美元增长到2012年的150亿美元。大约110亿美元的市场份额可以从具有成本效益的晶圆级封装中受益。众多工业界和学术界研究人员正在为新兴的MEMS市场开发封装解决方案，包括射频(RF)开关、微流体、微电池、红外(IR)传感器和生物医学设备。该项目中的技术将为所有这些设备提供通用的封装解决方案。这将对市场产生几个影响：1)它将使这些新兴的MEMS器件能够以具有成本效益的方式进行封装，帮助它们进入市场；2)它将简化生产价值链，允许MEMS设计者在不考虑其封盖技术的情况下选择最佳工艺/制造厂；3)它将通过允许研究人员专注于MEMS器件本身的功能而无需考虑封装设计来增强创新。

This Small Business Innovation Research (SBIR) Phase I project provides a universal capping technology for microelectromechanical systems (MEMS) and other microdevices. The technology will allow for thousands of moving MEMS devices to get protected from the environment in an inert gas or vacuum. The cap wafer technology itself has already been developed-the focus of this project is to develop a wide range of solder alloy bonding technologies which will allow for strong bonds, good electrical connectivity to the devices and vacuum/hermetic seals with virtually zero leak rates for a wide range of processes and device functionalities. The bond strengths will depend on the metal deposition conditions, the thermal budget before and after bonding and chemical reactions between each material (gold-indium, nickel-tin, silver-indium, silver-tin, copper-indium, etc.). Electrical characterization will involve optimizing the deposited metal stack in order to achieve low electrical resistances, optimized chemical potentials for ohmic contact and low paracitics. Initially the bond uniformity will be characterized by inspection, but will eventually be characterized with hermetically/vacuum sealed sensors allowing for fine leak rate measurement (10-15 cubic centimeters/second) and the characterization of outgassing (desorption of atoms from the microcavity surfaces), in order to characterizing the yield of functional hermetic/vacuum packages.The broader impact/commercial potential of this project is to provide a universal packaging technology for microelectromechanical systems (MEMS). Packaging (providing electrical connectivity and environmental protection) is generally the most difficult part of bringing MEMS to market. The MEMS market is expected to grow from $8 billion in 2008 to $15 billion by 2012. An approximately $11 billion portion of this market can benefit from cost efficient wafer-level packaging. A wide range of industrial and academic researchers are developing packaging solutions for emerging MEMS markets including radio frequency (RF) switches, microfluidics, micro-batteries, infrared (IR) sensors and biomedical devices. The technology in this project will provide a universal packaging solution for all of these devices. This will have several effects on the market: 1) It will allow for these emerging MEMS devices to be cost effectively packaged helping them get to market, 2) it will simplify the value chain for production allowing MEMS designers to choose the optimal process/manufacturing house without consideration of their capping technology and 3) it will enhance innovation by allowing researchers to focus on the functionality of the MEMS device itself without having to consider the package design.