Laminated ceramic electronic component and method for manufacturing same

• US 6,715,197 B2
• Filed: 05/22/2001
• Issued: 04/06/2004
• Est. Priority Date: 05/22/2000
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Okuyama, Shingo, Nakagawa, Tadahiro
• Primary Examiner(s): Donovan, Lincoln
• Assistant Examiner(s): Poker, Jennifer A.
• Application Number:
  US09/862,205
• Publication Number:
  US 20020008606A1
• Time in Patent Office: 1,050 Days
• Field of Search: 336/200, 296/021, 297/38, 297/45, 297/46, 298/30, 298/46, 361/301.4, 361/306.3, 361/307, 361/308.1, 361/309, 361/321.2
• US Class Current: 29/592.1
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 2017/0026 Multilayer LC-filter
• CPC Class Codes: H01F 41/043 by thick film techniques
• CPC Class Codes: H01G 4/30 Stacked capacitors H01G4/33 takes precedence
• CPC Class Codes: H03H 2001/0085 Multilayer, e.g. LTCC, HTCC, green sheets inside PCB filters H05K
• CPC Class Codes: H03H 3/00 Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H05K 3/4629 laminating inorganic sheets comprising printed circuits, e.g. green ceramic sheets
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/5317 Laminated device
• CPC Class Codes: Y10T 29/532 Conductor
• CPC Class Codes: Y10T 29/53204 Electrode

Abstract

A laminated ceramic electronic component significantly simplifies a step of forming external electrodes and has reliable electrical connection between an internal electrode and the external electrodes. A method for manufacturing the laminated ceramic electronic component includes the steps of forming composite sheets each having a conductor and a ceramic layer provided at the sides of the conductor on a carrier film, laminating the composite sheets with each other for forming a mother laminate, cutting the mother laminate in the thickness direction thereof so as to divide the conductor for forming laminates each forming one laminated ceramic electronic component, in which the conductor is exposed on the cut surface of the laminate, and firing the laminate so as to simultaneously form external electrodes from the exposed conductors and a sintered ceramic body.

Claims

1. A method for manufacturing a laminated ceramic electronic component, comprising the steps of:

forming composite sheets, each having a conductor portion and a ceramic layer portion, on a carrier film;

laminating the composite sheets with each other and separating each of the composite sheets from the carrier film to obtain a first laminated body;

cutting the first laminated body in a thickness direction thereof so as to divide the conductor portions to obtain at least one second laminated body having the conductor portions exposed on one of the cut surfaces; and

firing the at least one second laminated body to obtain a sintered ceramic body having an external electrode formed of the exposed conductor portions.

2. The method according to claim 1, wherein the laminating step includes the steps of press-bonding each of the composite sheets formed on the carrier film to a lamination stage or to a composite sheet that was previously laminated, separating the carrier film from each of the composite sheets, and repeating the steps of press bonding and separating.

3. The method according to claim 1, wherein the laminating step includes the steps of separating the composite sheets from the carrier films, laminating the composite sheets with each other after the separating step, and compressing the first laminated body in a thickness direction thereof.

4. The method according to claim 1, wherein the forming composite sheets step includes a step of printing the conductor portion and the ceramic layer portion at least two times so as to form each of the composite sheets.

5. The method according to claim 1, wherein the external electrode includes an edge surface portion extending along one of the cut surfaces exposed by the cutting and a pair of bent portions bent inside from the one of the cut surfaces at both ends of the edge surface portion.

6. The method according to claim 5, further comprising a step of cutting the first laminated body in a direction that is substantially perpendicular to the cut surface that includes the edge surface portion, wherein the at least one second laminated body formed during the cutting step has a substantially rectangular body having a pair of edge surfaces and a pair of side surfaces connecting therewith and the pair of bent portions are formed so as to extend along the pair of side surfaces.

7. The method according to claim 1, wherein the conductor portion of a composite sheet disposed at an outermost layer of the first laminated body has a pair of bent portions extending inside from an edge surface portion of the external electrode that is exposed by the cutting.

8. The method according to claim 5, wherein the external electrode having the edge surface portion and the pair of bent portions is formed such that an inner portion of a corner defined by the edge surface portion and the pair of bent portions has a substantially round shape.

9. The method according to claim 5, wherein the external electrode having the edge surface portion and the pair of bent portions is formed such that an outer portion of a corner defined by the edge surface portion and the bent portion has a substantially round shape.

10. The method according to claim 7, wherein a width of the edge surface portion of the external electrode increases toward the outermost layer of the at least one second laminated body along a laminating direction.

11. The method according to claim 7, wherein widths of the pair of bent portions of the external electrode increase toward the outermost layer of the at least one second laminated body along a laminating direction.

12. The method according to claim 1, wherein the forming step includes a step of forming a second conductor portion constituting an internal electrode which is performed at the same time that the conductor portion is formed.

13. The method according to claim 1, wherein in the firing step, the at least one second laminated body and a plurality of the external electrode are simultaneously formed.

14. The method according to claim 1, wherein a plurality of the external electrodes are formed during the step of firing and no additional steps are required for forming the plurality of external electrodes.

15. The method according to claim 1, further comprising a step of forming a plurality of internal electrodes and a plurality of external electrodes so as to be electrically connected to each other, wherein the plurality of internal electrodes and the plurality of external electrodes are fired at the same time during the step of firing.

16. A laminated ceramic electronic component manufactured according to the method of claim 1.

17. The method according to claim 1, wherein in the step of forming composite sheets, the conductor portion and the ceramic layer portion of each of the composite sheets do not overlap.

18. The method according to claim 15, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises an inductor.

19. The method according to claim 15, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises a capacitor.

58. The method according to claim 13, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises an LC filter.

20. A method for manufacturing a laminated ceramic electronic component, comprising the steps of:

forming composite sheets, each having a conductor portion and a ceramic layer portion, on a carrier film;

laminating the composite sheets with each other and separating each of the composite sheets from the carrier film to obtain a first laminated body;

cutting the first laminated body in a thickness direction thereof to obtain at least one second laminated body; and

firing the at least one second laminated body to obtain a sintered ceramic body, with the conductor portions forming a continuous external electrode on an edge surface of the laminated ceramic electronic component.

21. The method according to claim 20, wherein the laminating step includes the steps of press-bonding each of the composite sheets formed on the carrier film to a lamination stage or to a composite sheet that was previously laminated, separating the carrier film from each of the composite sheets, and repeating the steps of press bonding and separating.

22. The method according to claim 20, wherein the laminating step includes the steps of separating the composite sheets from the carrier films, laminating the composite sheets with each other after the separating step, and compressing the first laminated body in a thickness direction thereof.

23. The method according to claim 20, wherein the forming composite sheets step includes a step of printing the conductor portion and the ceramic layer portion at least two times so as to form each of the composite sheets.

24. The method according to claim 20, wherein the external electrode includes an edge surface portion extending along one of the cut surfaces and a pair of bent portions bent inside from the edge surface portion at both ends of the edge surface portion.

25. The method according to claim 24, further comprising a step of cutting the first laminated body in a direction that is substantially perpendicular to the cut surface that includes the edge surface portion, wherein the at least one second laminated body formed during the cutting step has a substantially rectangular body having a pair of edge surfaces and a pair of side surfaces connecting therewith and the pair of bent portions are formed so as to extend along the pair of side surfaces.

26. The method according to claim 20, wherein the conductor portion of one of the composite sheets disposed at an outermost layer of the first laminated body has a pair of bent portions extending inside from an edge surface portion of the external electrode.

27. The method according to claim 24, wherein the external electrode is formed such that an inner portion of a corner defined by the edge surface portion and the bent portion has a substantially round shape.

28. The method according to claim 24, wherein the external electrode is formed such that an outer portion of a corner defined by the edge surface portion and the bent portion has a substantially round shape.

29. The method according to claim 26, wherein a width of the edge surface portion of the external electrode increases toward the outermost layer of the at least one second laminated body along a laminating direction.

30. The method according to claim 26, wherein widths of the pair of bent portions of the external electrode increase toward the outermost layer of the at least one second laminated body along a laminating direction.

31. The method according to claim 20, wherein the forming step includes a step of forming a second conductor portion constituting an internal electrode which is performed at the same time that the conductor portion is formed.

32. The method according to claim 20, wherein in the firing step, the at least one second laminated body and a plurality of the external electrode are simultaneously formed.

33. The method according to claim 20, wherein a plurality of the external electrodes are formed during the step of firing and no additional steps are required for forming the plurality of external electrodes.

34. The method according to claim 20, further comprising a step of forming a plurality of internal electrodes and a plurality of external electrodes so as to be electrically connected to each other, wherein the plurality of internal electrodes and the plurality of external electrodes are fired at the same time during the step of firing.

35. A laminated ceramic electronic component manufactured according to the method of claim 20.

36. The method according to claim 20, wherein in the step of forming composite sheets, the conductor portion and the ceramic layer portion of each of the composite sheets do not overlap.

37. The method according to claim 34, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component is an inductor.

38. The method according to claim 34, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component is a capacitor.

59. The method according to claim 33, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises an LC filter.

39. A method for manufacturing a laminated ceramic electronic component, comprising the steps of:

forming composite sheets, each having a conductor portion and a ceramic layer portion, on a carrier film;

laminating the composite sheets with each other and separating each of the composite sheets from the carrier film to obtain a first laminated body;

cutting the first laminated body in a thickness direction thereof so as to obtain at least one second laminated body; and

firing the at least one second laminated body to obtain a sintered ceramic body with the conductor portions forming an external electrode, with at least a portion of the external electrode extending on at least one of the top and bottom surfaces of the laminated ceramic electronic component.

40. The method according to claim 39, wherein the laminating step includes the steps of press-bonding each of the composite sheets formed on the carrier film to a lamination stage or to a composite sheet that was previously laminated, separating the carrier film from each of the composite sheets, and repeating the steps of press bonding and separating.

41. The method according to claim 39, wherein the laminating step includes the steps of separating the composite sheets from the carrier films, laminating the composite sheets with each other after separating, and compressing the first laminated body in the thickness direction thereof.

42. The method according to claim 39, wherein the forming composite sheets step includes a step of printing the conductor portion and the ceramic layer portion at least two times so as to form each of the composite sheets.

43. The method according to claim 39, wherein the external electrode includes an edge surface portion extending along one of the cut surfaces exposed by the cutting and a pair of bent portions bent inside from the one of the cut surfaces at both ends of the edge surface portion.

44. The method according to claim 43, further comprising a step of cutting the first laminated body in a direction that is substantially perpendicular to the cut surface that includes the edge surface portion, wherein the at least one second laminated body formed during the cutting step has a substantially rectangular body having a pair of edge surfaces and a pair of side surfaces connecting therewith and the pair of bent portions are formed so as to extend along the pair of side surfaces.

45. The method according to claim 39, wherein the conductor portion of one of the composite sheets disposed at an outermost layer of the at least one second laminated body has a pair of bent portions extending inside from an edge surface portion of the external electrode.

46. The method according to claim 43, wherein the external electrode having the edge surface portion and the pair of bent portions is formed such that an inner portion of a corner defined by the edge surface portion and the pair of bent portions has a substantially round shape.

47. The method according to claim 43, wherein the external electrode having the edge surface portion and the pair of bent portions is formed such that an outer portion of a corner defined by the edge surface portion and the bent portion has a substantially round shape.

48. The method according to claim 45, wherein a width of the edge surface portion of the external electrode increases toward the outermost layer of the at least one second laminated body along a laminating direction.

49. The method according to claim 45, wherein widths of the pair of bent portions of the external electrode increase toward the outermost layer of the at least one second laminated body along a laminating direction.

50. The method according to claim 39, wherein the forming step includes a step of forming a second conductor portion constituting an internal electrode which is performed at the same time that the conductor portion is formed.

51. The method according to claim 39, wherein in the firing step, the at least one second laminated body and a plurality of the external electrodes are simultaneously formed.

52. The method according to claim 39, wherein a plurality of the external electrodes are formed during the step of firing and no additional steps are required for forming the plurality of external electrodes.

53. The method according to claim 39, further comprising a step of forming a plurality of internal electrodes and a plurality of external electrodes so as to be electrically connected to each other, wherein the plurality of internal electrodes and the plurality of external electrodes are fired at the same time during the step of firing.

54. A laminated ceramic electronic component manufactured according to the method of claim 39.

55. The method according to claim 39, wherein in the step of forming composite sheets, the conductor portion and the ceramic layer portion of each of the composite sheets do not overlap.

56. The method according to claim 53, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises an inductor.

57. The method according to claim 53, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises a capacitor.

60. The method according to claim 57, wherein the plurality of internal electrodes are arranged such that the laminated ceramic electronic component comprises an LC filter.

61. A method for manufacturing a laminated ceramic electronic component, comprising the steps of:

forming composite sheets, each having a conductor portion and a ceramic layer portion, on a carrier film;

laminating the composite sheets with each other to obtain a first laminated body;

cutting the first laminated body in a thickness direction thereof so as to divide the conductor portions to obtain at least one second laminated body having the conductor portions exposed on one of the cut surfaces; and

firing the at least one second laminated body to obtain a sintered ceramic body having an external electrode formed of the exposed conductor portions, wherein

the external electrode is formed on the left and right sides of the plurality of the composite sheets.