摘要 |
PROBLEM TO BE SOLVED: To provide a heater-integrated type oxygen sensor element capable of rapidly raising temperature, having a ceramic porous layer with high adherence, and having an electrode prevented from being poisoned by an exhaust gas. SOLUTION: This heater-integrated type oxygen sensor element is provided with a cylindrical tube 2 formed of a ceramic solid electrolyte and having one end sealed, a reference electrode 3 and a measurement electrode 4 formed at opposite positions of the inside surface and the outside surface of the cylindrical tube 2, respectively, a ceramic insulation layer 5 having an opening 6 formed so as to expose part or the whole part of the measurement electrode 4 with a heating element 7 embedded around the opening 6, a dense ceramic solid electrolyte layer 8 formed on the surface of the insulation layer 5, and the ceramic porous layer 11 overlaid so as to cover at least the opening 6 and the electrolyte layer 8 around it. A ceramic intermediate layer 12 having a thickness of 5-100 μm and a surface roughness Ra of 1.5-4 μm is formed between the electrolyte layer 8 and the porous layer 11. |