Method of producing solid electrolyte oxygen-sensing element of laminated structure with measuring electrode partially deposited from vapor phase

摘要

A method of producing an oxygen sensing element of the concentration cell type in the form of a lamination of relative thin layers. The first step of the method is to prepare a lamination of a ceramic shield layer (12) which serves as a substrate, an inner or reference electrode layer (16), an oxygen ion conductive solid electrolyte layer (18) and an outer or measurement electrode layer (20) which is porously formed by sintering an electronically conducting powder, preferably a cermet powder, applied to the solid electrolyte layer surface in the form of paste. To improve the responsiveness of the oxygen sensing element, an additional measurement electrode layer (24), preferably not thicker than 0.5 microns, is formed on the sintered measurement electrode layer (20) by a physical vapor deposition technique such as sputtering, ion plating or vacuum evaporation by using a mask formed with an opening through which only the outer surface of the sintered measurement electrode layer is exposed. IMAGE