Process Development and Die Shear Testing in MOEMS Packaging

Micro-Opto-electro-Mechanical Systems (MOEMS), which are MEMS integrated with photonics, share the traditional challenges of MEMS packaging with the additional issues of optical interconnects and optical surface contamination. Optoelectronic systems require signals through a package using fiber-optics, coaxial or other interconnection approaches. Precise optical component alignment and accurate thermal management is critical to achieve component and system performance capabilities. As the requirements for higher signal speeds and higher data rates grow, and as operating frequencies move to the higher GHz regions and beyond, the choice of packaging technology becomes critical. Optical MEMS packages not only have to provide electrical connections but also support high precision optics and mechanics, vital for operation of optical MEMS devices. Analogous to MEMS, packaging is also a critical path in reliability and cost of MOEMS devices. One of the commonly observed failures is the de-lamination between the chip (die) and the die attach. The focus of this paper is the development of a reliable fluxless die attachment process suitable for MOEMS assemblies with long operational life time. The reliability assessment was carried out at the Texas Microfactory™ at UT Arlington according to the MIL-STD-883F for die shear reliability.