Design and characterization of a humidity sensor realized in LTCC-technology

摘要

A new type of integrated temperature and humidity sensor applying Low Temperature Cofired Ceramics technology (LTCC) has been developed and characterized. The proposed device is based on the detection of the difference of thermal conductivity between water vapor and dry air. In this approach, sensing elements are implemented using heated metal film resistors (Pt-elements), where one is exposed to the humid environment that causes the sensor element to cool down with increased humidity, while the other one is sealed from the environment. LTCC-tapes are used for the formation of caps as well are acting as substrate. Sensor design is based on finite element analyses (FEA) where the critical design parameters have been analyzed with regard to the performance characteristic of the device.