chapter  4
34 Pages

Packaging, Processing, and Material Requirements for MEMS Devices

Properties of important etchants best suited for specific MEMS applications are summarized. Properties of thin-film materials needed in the fabrication of MEMS devices such as MEMS transducers, resonators, and accelerometers are identified. Packaging and sealing material requirements are summarized with emphasis on

coefficient of thermal expansion (CTE) match and mechanical integrity of the device. It is important to mention that rapid progress in the design, development, fabrication, and commercialization of MEMS and NT devices is contingent on the availability of advanced materials to the MEMS designers. In addition to traditional materials used in silicon microelectronics involving single crystals and polysilicon, silicon oxide (SiO), silicon nitride (Si3N4), and aluminum (Al), it is now possible to introduce and integrate a wide variety of metals, alloys, semiconductors, ceramics and glasses, polymers, and elastomers (polyimides) in the design of MEMS or NT devices. In summary, important properties of structural materials, high-quality factor (Q) dielectric ceramics, and low-loss electroplating materials best suited for fabrication of MEMS devices are summarized.