Multilayer ceramic substrate and manufacturing thereof

Abstract

A multilayer ceramic substrate includes stacked ceramic layers, and external electrodes including first conductive layers penetrating through one region of an outermost layer of the stacked ceramic layers to thereby be embedded therein, and second and third conductive layers sequentially stacked on the first conductive layers. Each of the first and second conductive layers is formed of a ceramic powder and a metal powder.

What is claimed is: 
     
         1 . A method for manufacturing a multilayer ceramic substrate, the method comprising:
 filling a through hole of a first ceramic sheet with a first conductive layer, and sequentially stacking second and third conductive layers on a surface of the first ceramic sheet to cover the first conductive layer;   forming a via electrode in a through hole of a second ceramic sheet;   forming an internal electrode on a surface of a third ceramic sheet; and   sequentially stacking the first through the third ceramic sheets on one another, and simultaneously firing the stacked first through third ceramic sheets, the via electrode, the internal electrode, and the first through third conductive layers,   wherein the internal electrode is electrically connected to the third conductive layer through the via electrode formed in the second ceramic sheet and the first conductive layer formed in the first ceramic sheet, and   each of the first and second conductive layers is formed of a ceramic powder and a metal powder.   
     
     
         2 . The method of  claim 1 , wherein a concentration of the ceramic powder in the first conductive layer is greater than that in the second conductive layer. 
     
     
         3 . The method of  claim 1 , wherein a compositional ratio of the ceramic powder and the metal powder in the first conductive layer is (20 to 30) wt % to (70 to 80) wt %. 
     
     
         4 . The method of  claim 1 , wherein a compositional ratio of the ceramic powder and the metal powder in the second conductive layer is (5 to 10) wt % to (90 to 95) wt %. 
     
     
         5 . The method of  claim 1 , wherein the firing is performed at a temperature equal to or higher than 800° C. 
     
     
         6 . The method of  claim 1 , a concentration of the ceramic powder increases from the third conductive layer to the first conductive layer.