Ceramic capacitive pressure sensor based on LTCC technology

This work is focused on the design and fabrication of a capacitive ceramic pressure sensor using LTCC technology. The multilayer technology helps us to tailor the thickness of the flexible membrane depending on the pressure range we are working in. In the bottom part of the substrate a entire signal conditioning electronics is located. An integrated circuit suitably chosen for this application measures the capacitance and converts it to a proportional voltage to the pressure. The present paper will deeply discuss technological details about LTCC technology applied to these devices, as well as hot aspects of the design such as planarity of the membrane, its thickness, gap between electrodes, electrodes and guard rings. Results of the devices taking into account these aspects will be also shown.