MEMS Packaging: Fluxless Soldering and Reliability Assessment

This thesis presents process development and reliability assessment of the fluxless packaging of the MEMS devices. This packaging consists of metallized Kovar package with side wall of same material and circular holes for the optical fiber interconnect between the microstructures on the chip and the macro-environment. The back of the MEMS chip and the soldering part of the optical fiber is metallized. A thin solder perform is placed between the chip and the metallized package to attach the chip and a circular solder perform is used to attach the fiber to the metal substrate. The soldering process is fluxless hence organic free. Selection of soldering environment and solders is studied. Different process parameters are evaluated to achieve the fluxless soldering. Once the bonding between the die and the package and the fiber and the package are achieved the joining is to be assessed with different reliability tests like die shear test, fiber pull test, impact and vibration test.