Theoretical investigation on hermeticity testing of MEMS packages based on MIL-STD-883E

In the present study, a gas flow model is used to show that the helium bomb test and bubble test methods in MIL-STD-883E are not applicable for hermeticity testing of packages with small internal volumes (<10⁻³ cm³), typically encountered for microelectromechanical systems (MEMS). The reasons include inaccurate reading due to helium loss in dwell period, undefined regime in leak rate spectrum, and unpractical reject limit for small vacuum packages. The simulation results indicate the necessity to develop new test methods for hermeticity testing of MEMS packages, such as to integrate pressure sensors in the package.