Ceramic Sensor Elements for Geothermal Applications

The harsh environmental conditions of geothermal applications restrict the applicable sensor materials to a small number. This is an application area for ceramic multilayer technology, which, thanks to the possibility of 3D structuring of ceramic materials, offers the possibility of producing cost-effective harsh environment sensors suitable for mass production. This requires the stability of all materials used for the sensor, such as the ceramic and functional layers. For this purpose, we tested ceramic materials, metallization’s, and inorganic cover layers regarding their suitability for use in geothermal environments and will present the stability of these materials under corrosive attack. Based on the material selection a ceramic piezoresistive high pressure sensory element was designed, manufactured, and characterized in laboratory environment and in application-specific test stands.