Pirani gauge based hermeticity monitoring for un-cooled micro bolometer array

This paper presents a novel method to analyze the thermal conductance under vacuum environment for MEMS devices. The Si/Ge-based Pirani gauge introduced is developed for monitoring the package hermeticity of MEMS Bolometer array, which has the total same structure as the single bolometer pixel for the characteristic of functional material. Meanwhile the ‘Extended Fourier's Law’ is verified by free molecular theory and is applied into the thermal analysis of the micro-structure under the pressure below 100Pa. Thermal interaction between Focus Plane Arrays (FPAs) and Pirani gauge is checked to guarantee the normal performance as the influence from each side are under 2×10 −3 K, which is acceptable for the products. This design can save the cost in fabrication significantly due to no extra process flow. The commercial value is affirmed by industry partner.