Hermeticity tests on organically sealed micro-packages using FTIR spectroscopy

摘要

This paper presents hermeticity tests carried out on organically sealed MEMS micro-packages, using Fourier Transform Infra Red (FTIR) spectroscopy. Infrared spectroscopy, classically dedicated to material analysis, can be used to monitor the internal pressure of micro-packages, and to assess so their hermeticity. This technique was applied to BCB sealed micro-packages to study the influence of different parameters on their hermeticity properties, like the sealing ring dimensions or the addition of an external coating. The technique was validated for silicon micro-packages with a volume of 5 mm~3 or more. Moreover, measurements carried out on micro-cavities with external parylene coatings have demonstrated that infrared spectroscopy measurements could be performed on MEMS packages with hermetic organic coatings.