Analysis of coupled diaphrams using coupled-mode theory

Diapharagm pressure sensors based on silicon micro-machining have advantages of small size and integrability with control electronics to form efficient MEMS applications. In this paper analysis of diaphragm based pressure sensors are presented by deriving the displacement function. Governing equations for individual diaphragms are given followed by analysis of a systems of two coupled diaphragms. Coupled mode theory is used to analyse the two diaphragm pressure sensor by expanding the combined mode fields in terms of individual modes of the single diaphragms. Results are presented for typical diaphragm parameters. Results indicate that coupled diaphragm sensors can be more efficient than single diaphragms sensors.