SENSOR ELEMENT FOR MEASURING PHYSICAL CHARACTERISTIC OF MEASUREMENT GAS

PROBLEM TO BE SOLVED: To manufacture a new sensor element without having uncontrolled dispersion of effective signals of the sensor element. SOLUTION: This sensor element is used for measuring a physical characteristic of a measurement gas, in particular, concentration of at least one kind of gas constituent in the measurement gas. The sensor element has one or more ceramic layers 11 and 12, a diffusion barrier 15 adjacent to the one or more ceramic layers 11 and 12, and formed of a base material having a silicon constituent and a yttrium constituent similarly to the ceramic layers 11 and 12, and at least one electrode 18 exposed to the measurement gas diffusing by penetrating the diffusion barrier 15. The sensor element is characterized in that the content of silicon in the diffusion barrier 15 is nearly equal to the content of silicon in the two or more ceramic layers 11 and 12, and the difference between them is not larger than 1 mass%. COPYRIGHT: (C)2009,JPO&INPIT