Methods for manufacturing ceramic green sheet and multilayer ceramic electronic parts

• US 6,607,690 B2
• Filed: 10/05/2001
• Issued: 08/19/2003
• Est. Priority Date: 10/06/2000
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Anahara, Toshiya, Nakamura, Ichiro
• Primary Examiner(s): Fiorilla, Christopher A.
• Application Number:
  US09/971,756
• Publication Number:
  US 20020125618A1
• Time in Patent Office: 683 Days
• Field of Search: 264/615, 264/614, 264/619, 264/650, 264/213
• US Class Current: 264/614
• CPC Class Codes: B32B 18/00 Layered products essentially comprising ceramics, e.g. refractory products
• CPC Class Codes: C04B 2235/658 Atmosphere during thermal treatment
• CPC Class Codes: C04B 2235/785 Submicron sized grains, i.e. from 0,1 to 1 micron
• CPC Class Codes: C04B 2237/346 Titania or titanates
• CPC Class Codes: C04B 35/6342 Polyvinylacetals, e.g. polyvinylbutyral [PVB]
• CPC Class Codes: H01G 4/12 Ceramic dielectrics H01G4/085 takes precedence
• CPC Class Codes: H01G 4/30 Stacked capacitors H01G4/33 takes precedence

Abstract

A ceramic green sheet is manufactured by preparing a support which includes a releasing layer formed on its top surface and has a smoothness that at least a region of the top surface of the support to be coated with a ceramic slurry has substantially no projections having a height of equal to or more than about 1 μm, and applying a ceramic slurry to the releasing layer of the support, which ceramic slurry contains a ceramic powder dispersed in a medium. This ceramic green sheet has a small thickness of, for example, about 0.3 to 3 μm, has no depressions or through holes caused by a filler in the support and is excellent in smoothness.

Claims

1. A method for manufacturing a ceramic green sheet for multilayer ceramic electronic parts by applying a ceramic slurry onto a support, the method comprising:

providing a support having top and bottom surfaces and having a releasing layer on its top surface and having a smoothness such that at least a region of the top surface of the support to be coated with a ceramic slurry has substantially no projections having a height of equal to or more than about 1 μ

m; and

applying a ceramic slurry comprising a ceramic powder dispersed in a medium to the releasing layer of the support.

2. The method according to claim 1, wherein the support has a smoothness such that at least a region of the bottom surface of the support has substantially no projections having a height of equal to or more than about 1 μ

m, and wherein said region of the bottom surface corresponds to the region of the top surface to be coated with the ceramic slurry.

3. The method according to claim 2, wherein the ceramic slurry is applied such that the resulting ceramic green sheet has a thickness of from about 0.3 to 3 μ

m.

4. The method according to claim 3, wherein the top surface of the support to be coated with the ceramic slurry has a coefficient of static friction and a coefficient of kinetic friction both of which are less than or equal to about 0.45.

5. The method according to claim 4, further comprising making said support.

6. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 5;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

7. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 4;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

8. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 2;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the sintered compact.

9. The method according to claim 1, wherein the ceramic slurry is applied such that the resulting ceramic green sheet has a thickness of from about 0.3 to 3 μ

m.

10. The method according to claim 9, wherein the top surface of the support to be coated with the ceramic slurry has a coefficient of static friction and a coefficient of kinetic friction both of which are less than or equal to about 0.45.

11. The method according to claim 10, further comprising making said support.

12. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 10;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

13. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 9;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

14. The method according to claim 1, wherein the top surface of the support to be coated with the ceramic slurry has a coefficient of static friction and a coefficient of kinetic friction both of which are less than or equal to about 0.45.

15. The method according to claim 14, further comprising making said support.

16. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 15;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

17. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 14;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

18. The method according to claim 1, further comprising making said support.

19. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 18;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the resulting sintered compact.

20. A method for manufacturing multilayer ceramic electronic parts, the method comprising:

forming a plurality of ceramic green sheets by the method as claimed in claim 1;

providing a base metal electrode on a surface of each of said ceramic green sheets;

laminating said electrode containing ceramic green sheets together to form a laminate;

firing said laminate to thereby yield a sintered compact; and

forming an electrode on an exterior surface of the sintered compact.