Multilayer ceramic substrate and manufacturing thereof

Patent metadata

Field	Value
Publication number	US-2016157341-A1
Application number	US-201514887108-A
Country	US
Kind code	A1
Filing date	Oct 19, 2015
Priority date	Dec 1, 2014
Publication date	Jun 2, 2016
Grant date	—

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.

First claim

What is claimed is:

1 . A multilayer ceramic substrate comprising:
a ceramic layer including a plurality of ceramic sheets stacked on one another; and external electrodes each including a first conductive layer penetrating through one region of an outermost ceramic sheet of the ceramic layer to thereby be embedded therein, and second and third conductive layers sequentially stacked on the first conductive layer, wherein each of the first and second conductive layers is formed of a ceramic powder and a metal powder.

2 . The multilayer ceramic substrate of claim 1 , wherein a concentration of the ceramic powder in the first conductive layer is higher than that in the second conductive layer.

3 . The multilayer ceramic substrate 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 multilayer ceramic substrate 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 multilayer ceramic substrate of claim 1 , wherein the third conductive layer is formed of the metal powder.

6 . The multilayer ceramic substrate of claim 1 , wherein the second conductive layer protrudes from an external surface of the ceramic layer.

7 . The multilayer ceramic substrate of claim 1 , wherein W 1 and W 2 satisfy W 1 ≦W 2 , in which W 1 is a width of the first conductive layer and W 2 is a width of the second conductive layer.

8 . The multilayer ceramic substrate of claim 1 , wherein the ceramic layer and the external electrode are co-fired.

9 . The multilayer ceramic substrate of claim 1 , wherein the ceramic powder of the first and second conductive layers is the same as that of the ceramic layer.

10 . The multilayer ceramic substrate of claim 9 , wherein the ceramic powder of the first and second conductive layers further contains at least one selected from magnesium carbonate (MgCO 3 ), barium carbonate (BaCO 3 ), calcium carbonate (CaCO 3 ), and silica (SiO 2 ).

11 . The multilayer ceramic substrate of claim 1 , wherein the third conductive layer covers an upper surface and side surfaces of the second conductive layer.

12 . The multilayer ceramic substrate of claim 1 , further comprising:
a plurality of internal electrodes and a plurality of via electrodes provided in the plurality of ceramic sheets of the ceramic layer, wherein some of the plurality of via electrodes contact the first conductive layer.

13 . The multilayer ceramic substrate of claim 1 , wherein the outermost ceramic sheet of the ceramic layer is at least one of uppermost or lowermost ceramic sheet thereof.

14 . The multilayer ceramic substrate of claim 1 , wherein a concentration of the ceramic powder increases from the third conductive layer to the first conductive layer.

15 . 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.

16 . The method of claim 15 , wherein a concentration of the ceramic powder in the first conductive layer is greater than that in the second conductive layer.

17 . The method of claim 15 , 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 %.

18 . The method of claim 15 , 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 %.

19 . The method of claim 15 , wherein the firing is performed at a temperature equal to or higher than 800° C.

20 . The method of claim 15 , a concentration of the ceramic powder increases from the third conductive layer to the first conductive layer.

Assignees

• Samsung Electro Mech

Inventors

• Lee Taek Jung
• Kim Yong Suk

Classifications

• H05K1/092 Primary

  Dispersed materials, e.g. conductive pastes or inks · CPC title

• H05K3/46 Primary

  Manufacturing multilayer circuits · CPC title

• H05K1/0306

  Inorganic insulating substrates, e.g. ceramic, glass · CPC title

• H05K1/0271

  Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion · CPC title

• H05K3/4644

  by building the multilayer layer by layer, i.e. build-up multilayer circuits (making via holes in the insulating layers H05K3/0011; special circuit boards as base or core whereon the multilayer is built H05K3/4602) · CPC title