Fabrication and Characterization of Gas-Sensitive Layers Based on Nanocrystalline Materials

A new generation of solid state sensors based on nanocrystalline BaTiO3 films containing various semiconducting oxides has been developed. The sensors were fabricated from BaTiO3 based nanopowder mixtures using thick film technology and were characterized regarding their CO2-gas sensitivity at different operation temperatures and gas environments. It was found that the sensors operate over a wide range of CO2 concentrations. Interfering gases have only minor effects on the sensor response. By using miniaturized Al2O3-substrates as carriers for the sensitive nanocrystalline layer a significant decrease of the power and powder consumption for each sensor was achieved.