Articles | Volume 5, issue 1
J. Sens. Sens. Syst., 5, 85–93, 2016

Special issue: High-temperature sensors and materials

J. Sens. Sens. Syst., 5, 85–93, 2016

Review paper 17 Mar 2016

Review paper | 17 Mar 2016

Investigation of low-temperature cofired ceramics packages for high-temperature SAW sensors

Jochen Bardong1, Alfred Binder1, Sasa Toskov2, Goran Miskovic2, and Goran Radosavljevic2 Jochen Bardong et al.
  • 1Carinthian Tech Research, Europastraße 4/1, Villach, Austria
  • 2Institute of Sensor and Actuator Systems, Gusshausstrasse 27–29, Vienna, Austria

Abstract. Surface acoustic wave (SAW) temperature sensor devices have been developed for operating temperatures up to and above 1000 °C. A challenging task to make these devices available on the market is to develop an appropriate housing concept. A concept based on low-temperature cofired ceramics (LTCC) has been investigated and tested under elevated temperatures up to 600 °C. The devices showed promising results up to 450 °C. Thorough analysis of the possible failure mechanisms was done to increase the maximum temperature above this limit in further production cycles.

Short summary
In this work, a ceramic housing was designed using the versatile low-temperature cofired ceramics (LTCC) to test this technology at temperatures above 400°C. Inside the housing, a prototype sensor chip was mounted to monitor the signal quality during an applied heat treatment up to 600 °C. All devices failed at around 450–500 °C due to material migration from the glass seal of the housing to the sensing structures of the mounted chip. Elemental analysis identified bismuth as a contaminant.