| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly durable gas sensor and its manufacturing method by preventing generation of cracks between a poisoning prevention layer and a solid electrolyte body. SOLUTION: A diffusion rate-determining layer 21a and the poisoning prevention layer 22a are arranged from the side of a measurement gas chamber 7 to a communication hole 19a through which the measurement gas chamber 7 communicates with the outside. Side faces of the diffusion rate-determining layer 21a and the poisoning prevention layer 22a are kept in contact with each other. The poisoning prevention layer 22a essentially consists of calcium phosphate, and moreover, contains zirconia. To upper and lower faces of the poisoning prevention layer 22a, i.e., to faces of the poisoning prevention layer 22a in touch with solid electrolyte substrates 3a and 5a, there are set diffusion prevention layers 24a1 and 24a2 essentially consisting of alumina (namely, formed of a high-purity alumina) all over the faces of the poisoning prevention layer 22a so as to prevent contact between the poisoning prevention layer 22a and the solid electrolyte substrates 3a, 5a. |
