Monolithic Ceramic IR-Emitter for Gas Analyzer

The results developed in a research project resulted from the cooperation between Fraunhofer IKTS in the field of ceramic multilayer technology and InfraTec GmbH in the field of infrared sensors and measurement technology and were generated within the project’s duration of 4 years. New types of miniature heaters embedded in ceramics were developed and their properties regarding modulation, spectral emission, long term and high temperature stability were characterized and optimized. A new process chain based on ceramic multilayer technology was developed to produce the IR emitter, which is based on a combination of sacrificial paste technology using screen or stencil printing and Low Temperature Cofired Technology (LTCC) processing. The generated dielectric layer thicknesses of 15-20 µm are half as thick as with conventional LTCC tape manufacturing processes. To optimize the emission coefficient towards a black body, new ceramic pastes suitable for screen printing have been developed. In this way, black surfaces could be created on the radiators, which are characterized by high temperature stability and low thermal mass. First long-term studies of the IR emitter up to 2000 hours show functionality at 650 °C with low degradation.