MEMS Packaging

Adhesives in both paste and film form have been used to attach and seal ceramic or metal lids to cavity packages that may also be ceramic or metal. These packages cannot be considered hermetic in the sense that seam-sealed, welded, or soldered fids are, but they are adequate for most commercial and consumer electronics where extreme moisture-temperature environments are not encountered. Packages sealed with Epo-Tek H77 epoxy adhesive are reported to provide near-hermetic sealing of hybrid microcircuits, integrated-circuit devices, and MEM packages withstand 100 hours of 95% relative humidity."... 

Walwadkar S, Cho J. Evaluation of die stress in MEMS packaging experimental and theoretical approaches. IEEE Trans Comp Packaging Technol. Dec. 2006 Vol. 29(Issue 4) 735-742. 

Wafer Bonding with intermediate Layers Wafers can be bonded using intermediate layers such as metals to form hermetic seals. Polymers, in general, do not provide water-tight sealing and are hence less important in the field of MEMS packaging. Soft metals such as indium can be bonded with silicon with a gold passivation [4]. Aluminum has been used to bond with silicon dioxide [5] and silicon nitride [6] to form hermetic seals. 

Many testing methods are available to evaluate the reliability of an IC/MEMS package. For example, if the dominant failure mode of a MEMS device is water condensation in the package, autoclave tests are available to test the... 

Due to the diversity of MEMS devices, MEMS packaging methodology is device and application dependent. Compromise solutions between cost, reliability, and process compatibility need to be considered. 

Electronic packaging IC packaging MEMS packaging Definition... 

Hetsroni G, Mosyak A, Segal Z (2001) Nonuniform temperature distribution in electronic devices cooled by flow in parallel micro-channels. IEEE Trans Comp Packag Technol 24(1) 16-23 Ho CM, Tai Y-C (1998) Micro-electronic mechanic systems (MEMS) and fluid flows. Ann Rev Fluid Mech 30 5-33... 

J. Kruckow, Packaging of bio-MEMS strategies, technologies, and applications. IEEE Trans. Adv. Packaging 28, 533-546 (2005). 

The packaging strategy presented in Sect. 5.1.6 can be directly applied to this array chip (see Fig. 6.15). The number of necessary bond pads is only five, since this chip takes full advantage of the CMOS-MEMS approach. The number of bondpads... 

H. Baltes, O. Brand, and M. Waelti. Packaging of CMOS MEMS , Microelectronics Reliability LO (2000), 1255-1262. 

The above discussion provides the context for 3-D batteries. That is, there are a variety of small power applications, typified by MEMS devices, which the most advanced, 2-D lithium battery systems are unable to satisfy. The inability to provide sufficient power is because of configuration and not because of intrinsic energy density. Three-dimensional designs offer the opportunity to achieve milliwatt-hour energies in cubic millimeter packages and, more importantly, with square millimeter footprints. While such power sources may not influence the enormous commercial markets in cell phones and laptop computers, they are certain to impact emerging markets where... 

The obvious advantage of the symmetrical arrangement is that the processes at all internal interfaces can be well defined and that most nonidealities at the mem-brane/solution interface tend to cancel out. Because the volume of the internal reference compartment is typically a few milliliters, the electrode does not suffer from exposure to electrically neutral compounds that would penetrate the membrane and change the composition of this solution. This type of potentiometric ion sensor has been used in the majority of basic studies of ion-selective electrodes. Most commercial ion-selective electrodes are also of this type. The drawbacks of this arrangement are also related to the presence of the internal solution and to its volume. Mainly for this reason, it is not conveniently possible to miniaturize it and to integrate it into a multisensor package. 

Grosser, V., Microfabrication of modular MEMS - assembly and reliability, in Proceedings of the Conference on Design, Test, Integration and Packaging of MEMS/ MOEMS, DTPI 2002 (5-8 May 2002), Cannes Mandelieu, 2002. 

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