PROCESSING METHOD OF OXYGEN-CONCENTRATION DETECTOR AND OXYGEN CONCENTRATION DETECTOR OBTAINED BY SUCH METHOD AND THE LIKE

摘要

PURPOSE:To stabilize output characteristics, to improve reproducibility and to obtain an output value in high accuracy by making specified ACs flow through two pairs of electrodes under the states wherein the electrodes are heated and maintained at a specified temperature. CONSTITUTION:An annular-plate-shaped outer pump electrode 24 is provided around a gas introducing hole 14 in the outer surface of a solid-state electrolyte layer 20. An annular-plate-shaped inner pump electrode 26 is provided on the surface of the electrolyte layer 20 on the side where a flat space 12 is formed. An annular-plate- shaped measuring electrode 30 is provided on the surface of an electrolyte layer 22 on the side where the flat space 12 is formed. An annular-plate-shaped reference electrode 32 is provided on the surface of the electrolyte layer 22 which is exposed in an air path 18. Under the state wherein a detector is heated to 600 deg.C or higher and maintained, ACs which have the values 1 - 5 times the respective diffusing-limit current value and the frequencies of 10kHz or lower are conducted across the electrodes 24 and 26 and the electrodes 30 and 32. The surfaces of the metal particles of the electrodes 26 and 30 are dense.