Electroconductive paste, and method for producing ceramic substrate using it

• US 5,985,461 A
• Filed: 11/17/1997
• Issued: 11/16/1999
• Est. Priority Date: 12/04/1996
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Ohshita, Kazuhito, Tani, Hiroji
• Primary Examiner(s): Speer, Timothy
• Assistant Examiner(s): STEIN, STEPHEN J
• Application Number:
  US08/971,496
• Time in Patent Office: 729 Days
• Field of Search: 428/433, 428/209, 428/432, 428/323, 428/327, 428/901, 428/689, 156/89.18, 156/89.16, 156/89.11, 252/512, 106/1.13, 106/1.18
• US Class Current: 428/433
• CPC Class Codes: B32B 3/08 characterised by added members at particular parts layer formed of separate pieces of material which are juxtaposed side-by-side B32B3/14, B32B3/18
• CPC Class Codes: H01L 23/49883 the conductive materials containing organic materials or pastes, e.g. for thick films for printed circuits H05K1/092
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 1/092 Dispersed materials, e.g. conductive pastes or inks
• CPC Class Codes: H05K 3/4053 by thick-film techniques
• CPC Class Codes: H05K 3/4629 laminating inorganic sheets comprising printed circuits, e.g. green ceramic sheets
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

Provided is an electroconductive paste for forming via-holes through ceramic substrates, and a method for producing ceramic substrates using the paste. The via-holes formed with the paste crack little during baking, and have high electric reliability and good solderability and platability. The paste comprises from about 80 to 93% by weight of a spherical or granular electroconductive metal powder having a grain size range of between about 0.1 and 50 μm, from about 2 to 10% by weight of an insoluble resin powder having a grain size range of between about 0.1 and 50 μm, and from about 5 to 18% by weight of an organic vehicle. The via-holes 2 formed through a ceramic green sheet 1 are filled with the paste 1, and a plurality of those ceramic green sheets 1 are laminated under heat and baked under a predetermined condition to produce a multi-layered ceramic substrate 6.

Claims

1. An electroconductive paste for use in forming via-holes in ceramic substrates, comprising

from about 80 to 93% by weight of an electroconductive metal powder having a spherical or granular shape and a grain size range between about 0.1 and 50 μ

m,

from about 5 to 18% by weight of an organic vehicle, and

from about 2 to 10% by weight of resin powder selected from the group consisting of ethyl cellulose resin and crystalline cellulose resin, having a grain size range between about 0.1 and 50 μ

m and which is insoluble in the organic vehicle and decomposable upon baking.

2. The electroconductive paste according to claim 1, wherein the electroconductive metal powder is copper powder.

3. An electroconductive paste for use in forming via-holes in ceramic substrates, comprising

from about 80 to 93% by weight of an electroconductive metal powder having a spherical or granular shape and a grain size range between about 0.1 and 50 μ

m,

from about 2 to 10% by weight of a crystalline cellulose powder having a grain size range between about 0.1 and 50 μ

m, and

from about 5 to 18% by weight of an organic vehicle.

4. The electroconductive paste according to claim 3, wherein the electroconductive metal powder is copper powder.

5. A ceramic substrate having a via-hole in which an electroconductive paste is present, said electroconductive paste comprising

from about 80 to 93% by weight of an electroconductive metal powder having a spherical or granular shape and a grain size range between about 0.1 and 50 μ

m,

from about 5 to 18% by weight of an organic vehicle, and

from about 2 to 10% by weight of resin powder selected from the group consisting of ethyl cellulose resin and crystalline cellulose resin, having a grain size range between about 0.1 and 50 μ

m and which is insoluble in the organic vehicle and decomposable upon baking.

6. The ceramic substrate according to claim 5, wherein the electroconductive metal powder is copper powder.

7. A ceramic substrate having a via-hole in which an electroconductive paste is present, said electroconductive paste comprising

from about 80 to 93% by weight of an electroconductive metal powder having a spherical or granular shape and a grain size range between about 0.1 and 50 μ

m,

from about 2 to 10% by weight of a crystalline cellulose powder having a grain size range between about 0.1 and 50 μ

m, and

from about 5 to 18% by weight of an organic vehicle.

8. The ceramic substrate according to claim 7, wherein the electroconductive metal powder is copper powder.

9. A method for producing ceramic substrates, comprising the steps offorming a hole in a ceramic green sheet,filling the hole with an electroconductive paste,laminating a plurality of said ceramic green sheets to produce a laminate, andbaking the resulting laminate,

wherein the electroconductive paste comprises

from about 80 to 93% by weight of an electroconductive metal powder having a spherical or granular shape and a grain size range between about 0.1 and 50 μ

m,

from about 5 to 18% by weight of an organic vehicle, and

from about 2 to 10% by weight of resin powder selected from the group consisting of ethyl cellulose resin and crystalline cellulose resin, having a grain size range between about 0.1 and 50 μ

m and which is insoluble in the organic vehicle and decomposable upon baking.

10. A method according to claim 9, wherein the electroconductive metal powder is copper powder.

11. A method for producing ceramic substrates, comprising the steps offorming a hole in a ceramic green sheet,filling the hole with an electroconductive paste,laminating a plurality of said ceramic green sheets to produce a laminate, andbaking the resulting laminate,

wherein the electroconductive paste comprises

from about 80 to 93% by weight of an electroconductive metal powder having a spherical or granular shape and a grain size range between about 0.1 and 50 μ

m,

from about 2 to 10% by weight of a crystalline cellulose powder having a grain size range between about 0.1 and 50 μ

m, and

from about 5 to 18% by weight of an organic vehicle.

12. A method according to claim 11, wherein the electroconductive metal powder is copper powder.