Stacked ceramic body and production method thereof

Abstract

This invention provides a stacked ceramic body that prevents reaction between components of dielectric layers and components of electrode layers of an unsintered stacked body during sintering and in which both components do not easily form a liquid phase, and a production method of such a stacked ceramic body. A print portion 13 is formed on a green sheet 1, 12 containing lead by use of an electrode paste consisting of copper oxide as its main component. A desired number of print sheets 10 are stacked to give an unsintered stacked body 15 . Degreasing is conducted in an atmosphere to degrease organic components. The print portion 13 is subjected to reducing treatment in a reducing atmosphere containing hydrogen and is converted to a print portion 13 containing copper as its main component. The unsintered stacked body 15 is sintered in a reducing atmosphere. Dielectric layers containing lead and electrode layers for applying a voltage to the dielectric layers are alternately stacked, and an oxidation portion containing copper is formed in the proximity of a surface of the electrode layer. A thickness of the oxidation portion in a stacking direction is 0.5 to 2 μm and a copper content in the oxidation portion is 1 to 30 wt %.

1 .- 11 . (canceled)  
   
   
       12 . A stacked ceramic body produced by a method comprising the steps of: 
 arranging a printed portion formed of an electrode paste consisting of copper or a copper compound as its main component on a green sheet formed of an oxide dielectric containing a lead oxide as its constituent element to form a print sheet;    stacking a plurality of said print sheets to form an unsintered stacked body;    conducting degreasing treatment by heat-treating for removing organic components contained in said unsintered stacked body; and    sintering said unsintered stacked body in a reducing atmosphere while controlling an oxygen partial pressure from room temperature to 400 to 600° C. to an oxygen partial pressure at which copper and lead oxide can coexist, or an oxygen partial pressure higher than said oxygen partial pressure at which copper and lead oxide can coexist,    wherein dielectric layers containing lead and electrode layers containing copper for applying a voltage to said dielectric layers are alternately stacked, and exposed portions of said electrode layers and portions in the proximity of said exposed portions are oxidation portions.    
   
   
       13 . A stacked ceramic body according to  claim 12 , wherein an oxidation width of said oxidation portion measured in a direction vertical to a stacking direction of said electrode layers is 0.05 to 2 mm.  
   
   
       14 . A stacked ceramic body according to  claim 12 , wherein a diffusion portion in which at least one kind of component constituting said electrode layer is diffused exists in the proximity of an interface with said electrode layer in said dielectric layer.  
   
   
       15 . A stacked ceramic body according to  claim 14 , wherein copper originating from said electrode layer is in a diffused state in said diffusion portion, a diffusion distance from the interface between said dielectric layer and said electrode layer in said diffusion portion is 0.5 to 2 μm, and a copper content in said diffusion portion is 0.1 to 30 wt %.  
   
   
       16 . A stacked ceramic body according to  claim 12 , wherein said stacked ceramic body is a piezoelectric device.