Heating power-controlled micro-gas sensor array

A new type micro-gas sensor array and its operating mode were proposed in t his paper. Sensor array has a heater, and three sensing electrode and tempe rature sensor pairs. Three different sensing materials, Fe2O3 + V2O5, SnO2/ Au + Pd and nanocrystalline SnO2, were synthesized by coprecipitation metho d and used for selective gas sensing. Even though fabricated sensor array h as three sensing materials, 12 sensing responses in an array were implement ed by using heating power-control method as a sensor operating mode. The ga s-sensing characteristics were investigated as a function of the heating po wers (35, 40, 45, and 50 mW). Principal component analysis (PCA) was employ ed to discriminate the various kinds of gases, which is known as one of the most effective sensing signal analysis methods. From the PCA result, we co uld confirm that the gas sensor array with excellent gas discriminating abi lity could be obtained by using a heating power-controlled method. (C) 2001 Elsevier Science B.V. All rights reserved.