Assembly Technologies for Piezoelectric Sensors up to 1000 °C

The realization of sensors with high sensitivity and low measurement uncertainty at temperatures up to 1000 °C is a major challenge. The use of CTGS resonators is a sufficient prerequisite, since thermal stability and a high resonance quality are given. However, a hermetic housing is indispensable to keep unwanted environmental influences away. In this work, we consider assembly technologies for piezoelectric sensors which are used for high temperatures. Possible material combinations as well as their material properties are examined. Challenges for the development of high temperature sensors with these materials are the packaging technology and the electrical connections. Electrical, thermal and mechanical influences of the assembly technology on the sensor signals up to 1000°C have been largely unexplored up to now, as have fundamental questions on hermeticity and damage mechanisms under permanent or changing high temperature loads. This research work will establish a method to develop a sensor housing that is stable for operations up to 1000 °C and also a final implementation of this concept is shown.