Challenges in interconnection and packaging of microelectromechanical systems (MEMS)

Integrated circuit packaging and their testing is well advanced because of the maturity of the IC industry, their wide applications, and availability of industrial infrastructure. This is not true for MEMS with respect to packaging and testing. It is more difficult to adopt standardized MEMS device packaging for wide applications although MEMS use many similar technologies to IC packaging. Packaging of MEMS devices is more complex since in some cases it needs to provide protection from the environment while in some cases allowing access to the environment to measure or affect the desired physical or chemical parameters. Microscopic mechanical moving parts of MEMS have also their unique issues. Therefore, testing MEMS packages using the same methodologies, as those for electronics packages with standard procedures might not always be possible especially when quality and reliability need to be assessed. Single MEMS chip packaging approaches and their limitations in the packaging of high performance MEMS will be reviewed in this presentation and also identifies a need for a systematic approach for this purpose. MEMS package reliability depends on package type, i.e. ceramic, plastic, or metal, and reliability of device. The MEMS device reliability depends on its materials and wafer level processes and sealing methods used for environmental protection. MEMS quality and reliability challenges are discussed and needs for study in these areas are identified.