M.Santo-Zarnik, D.Belavic, S.Macek, F.Novak.
Fault diagnosis based of a finite-element model of a piezoresistive ceramic pressure sensor,
Proc. 11th Int. Mixed-Signals Testing Workshop, IMSTW'05, pp. 171-178, Cannes, France, June 27-29, 2005.

In this paper we present our experience in fault diagnosis of a piezoresistive ceramic pressure sensor based on a finite-element model. The sensor was designed using low-temperature cofired ceramic technology (LTCC). The sensing elements were thick-film resistors acting as strain gauges, which translate the strain into an electrical signal. The sensitivity of the sensor to the applied pressure depends on the construction, the material properties of the diaphragm, and the piezoresistive properties of the thick-film resistors and the location of the sensing resistors. In the design phase, a finite-element analysis was used to reveal the strain distribution in the sensing structure and analyse the sensitivity of the thick-film resistors to the applied pressure. The finite-element model was experimentally verified and validated by comparing the simulation results to the measured characteristics of a set of test specimens. The model serves for fault diagnosis and troubleshooting of the existing prototype series. Some experimental case studies will illustrate the approach.