Physical characterisation of selective stress coupline for resonant pressure sensors

This paper presents a selective stress coupling structure for resonant sensor applications. The structure is designed to selectively couple a resonant strain gauge into strain in one degree of freedom only. It constrains the displacement of the resonator such that it always stays aligned. A resonant pressure sensor is proposed that incorporates the stress isolation chip to allow a resonant strain gauge to be mounted to a large pressure sensitive silicon diaphragm. The chip behavior has been modeled using finite element analysis. Physical testing using a Wyko non-contact surface profiler has been carried out to investigate the selective stress coupling structure performance. (C) 2004 Elsevier B.V. All rights reserved.