B1.3 - Design Study of a Wireless Pressure Sensor for Medical Application

This work provides crucial contributions for an implantable wireless sensor proposed for epidural or subdural brain pressure monitoring. We designed a pressure sensor based on SAW (surface acoustic wave) reflective delay lines on a diaphragm. FEM simulations were used to optimize the sensitivity, size and mechanical stability of the device. We have chosen a design that allows maximizing the sensor effect, while simultaneously providing temperature compensation. A production process for SAW membrane sensors on lithiumniobate was developed. It integrates different methods for the production of thin membranes like ultra sound drilling and laser processing as well as the protection of the sensitive SAW structures. We fabricated prototypes that demonstrated encouraging behavior in wired and wireless measurements in a pressure chamber.