Monolithic ceramic electronic component and production process therefor, and ceramic paste and production process therefor

• US 6,599,463 B2
• Filed: 12/13/2000
• Issued: 07/29/2003
• Est. Priority Date: 12/13/1999
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kimura, Koji, Kato, Koji, Suzuki, Koji, Tanaka, Satoru, Miyazaki, Makoto
• Primary Examiner(s): DERRINGTON, JAMES H
• Application Number:
  US09/735,879
• Publication Number:
  US 20010006451A1
• Time in Patent Office: 958 Days
• Field of Search: 264/614, 264/615, 264/616, 264/617, 264/618, 264/669, 264/670, 156/89.12
• US Class Current: 264/614
• CPC Class Codes: B32B 18/00 Layered products essentially comprising ceramics, e.g. refractory products
• CPC Class Codes: B32B 2038/042 Punching
• CPC Class Codes: B32B 2311/08 Silver
• CPC Class Codes: B32B 2311/12 Copper
• CPC Class Codes: B32B 2311/22 Nickel or cobalt
• CPC Class Codes: B32B 37/0046 characterised by constructional aspects of the apparatus
• CPC Class Codes: B32B 38/145 Printing
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3262 Manganese oxides, manganates, rhenium oxides or oxide-forming salts thereof, e.g. MnO
• CPC Class Codes: C04B 2235/3275 Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
• CPC Class Codes: C04B 2235/3279 Nickel oxides, nickalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/36 Glass starting materials for making ceramics, e.g. silica glass
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2237/06 Oxidic interlayers
• CPC Class Codes: C04B 2237/064 based on alumina or aluminates
• CPC Class Codes: C04B 2237/068 based on refractory oxides, e.g. zirconia
• CPC Class Codes: C04B 2237/08 Non-oxidic interlayers
• CPC Class Codes: C04B 2237/083 Carbide interlayers, e.g. silicon carbide interlayers
• CPC Class Codes: C04B 2237/09 wherein the active component for bonding is not the largest fraction of the interlayer
• CPC Class Codes: C04B 2237/405 Iron metal group, e.g. Co or Ni
• CPC Class Codes: C04B 2237/407 : Copper
• CPC Class Codes: C04B 2237/408 : Noble metals, e.g. palladium, platina or silver
• CPC Class Codes: C04B 2237/50 : Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
• CPC Class Codes: C04B 2237/68 : Forming laminates or joining articles wherein at least one substrate contains at least two different parts of macro-size, e.g. one ceramic substrate layer containing an embedded conductor or electrode
• CPC Class Codes: C04B 35/053 : Fine ceramics
• CPC Class Codes: C04B 35/111 : Fine ceramics
• CPC Class Codes: C04B 35/2658 : Other ferrites containing manganese or zinc, e.g. Mn-Zn ferrites
• CPC Class Codes: C04B 35/46 : based on titanium oxides or titanates containing also zirconium or hafnium oxides, zirconates or hafnates C04B35/49
• CPC Class Codes: C04B 35/468 : based on barium titanates
• CPC Class Codes: C04B 35/486 : Fine ceramics
• CPC Class Codes: C04B 35/491 : based on lead zirconates and lead titanates , e.g. PZT
• CPC Class Codes: C04B 35/565 : based on silicon carbide
• CPC Class Codes: C04B 35/584 : based on silicon nitride
• CPC Class Codes: C04B 35/6264 : Mixing media, e.g. organic solvents
• CPC Class Codes: C04B 35/63 : using additives specially adapted for forming the products , e.g.. binder binders
• CPC Class Codes: C04B 35/632 : Organic additives
• CPC Class Codes: C04B 35/634 : Polymers C04B35/636 takes precedence
• CPC Class Codes: C04B 35/63416 : Polyvinylalcohols [PVA]; Polyvinylacetates
• CPC Class Codes: C04B 35/63424 : Polyacrylates; Polymethacrylates
• CPC Class Codes: C04B 35/636 : Polysaccharides or derivatives thereof
• CPC Class Codes: C04B 35/6365 : Cellulose or derivatives thereof
• CPC Class Codes: C04B 35/638 : Removal thereof
• CPC Class Codes: C04B 37/005 : consisting of glass or ceramic material
• CPC Class Codes: H01C 7/003 : Thick film resistors
• CPC Class Codes: H01C 7/18 : comprising a plurality of layers stacked between terminals
• CPC Class Codes: H01F 17/0013 : with stacked layers
• CPC Class Codes: H01F 41/043 : by thick film techniques
• CPC Class Codes: H01F 41/046 : structurally combined with ferromagnetic material
• CPC Class Codes: H01G 4/12 : Ceramic dielectrics H01G4/085 takes precedence
• CPC Class Codes: H01G 4/30 : Stacked capacitors H01G4/33 takes precedence
• CPC Class Codes: H01L 21/4857 : Multilayer substrates multilayer metallisation on monolayer substrate H01L21/4846

Abstract

A process for producing a monolithic ceramic electronic component, which includes: providing a ceramic slurry, a conductive paste, and a ceramic paste; forming a plurality of composite structures each comprising a ceramic green sheet produced by shaping the ceramic slurry, internal circuit element films formed by applying the conductive paste partially onto a main surface of the ceramic green sheet so as to provide step-like sections, and a ceramic green layer which compensates for spaces defined by the step-like sections, the ceramic green layer being formed by applying the ceramic paste onto the region on the main surface of the sheet on which the element films are not formed, so as to substantially compensate for the spaces; forming a green laminate by laminating the composite structures; and firing the green laminate, wherein the ceramic paste contains ceramic powder, an organic solvent, and an organic binder. A monolithic ceramic electronic component produced through the process; a ceramic paste; and a production process for the ceramic paste are also disclosed.

Claims

1. A process for producing a monolithic ceramic electronic component, which comprises:

forming a composite structure by shaping the ceramic slurry into a ceramic green sheet having a main surface, applying a conductive paste onto a portion of the main surface of the ceramic green sheet so as to provide step-like section of an internal circuit element film, and applying a ceramic paste onto the region on the main surface of the sheet on which the element film has not been formed so as to form a ceramic green layer which substantially compensates for the spaces defined by the step-like section;

forming a green laminate by laminating a plurality of the composite structures; and

firing the green laminate,

wherein the ceramic paste comprises ceramic powder, an organic solvent and an organic binder, and

wherein the organic binder comprises a member selected from the group consisting of (a) a mixture of polyvinyl butyral and cellulose ester, (b) a mixture of a polyacrylate and a cellulose ester, (c) a mixture of polyvinyl butyral and polyvinyl acetate and (d) a mixture of polyvinyl butyral and a polyacrylate, and wherein the binder mixtures are at a weight ratio of about 10;

90 to 90;

10.

2. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the binder comprises a mixture of polyvinyl butyral and cellulose ester.

3. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the binder comprises a mixture of a polyacrylate and a cellulose ester.

4. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the binder comprises a mixture of polyvinyl butyral and polyvinyl acetate.

5. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the binder comprises a mixture of polyvinyl butyral and a polyacrylate.

7. A process for producing a monolithic ceramic electronic component according to claim 1, further comprising preparing the ceramic paste by

dispersing a first mixture comprising ceramic powder and a first organic solvent in the absence of organic binder to provide a primary dispersion;

dispersing a second mixture comprising organic binder and the primary dispersion to provide a secondary dispersion; and

removing the first organic solvent from the secondary dispersion by heating the secondary dispersion,

wherein a second organic solvent having a relative evaporation rate lower than that of the first organic solvent is incorporated into the first mixture or the second mixture or both.

8. A process for producing a monolithic ceramic electronic component according to claim 7, wherein the ceramic slurry and the ceramic past each contain a ceramic powder of substantially the same composition;

the amount of binder is about 1 to 20 wt. % based on the ceramic;

the first organic solvent has a relative evaporation rate of at least 100; and

the second organic solvent has a relative evaporation rate of less than about 50 and a boiling point of at least about 150°

C.

9. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the ceramic slurry and the ceramic paste each contain a ceramic powder of substantially the same composition.

10. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the ceramic slurry and the ceramic paste each contain a dielectric ceramic powder.

11. A process for producing a monolithic ceramic electronic component according to claim 10, wherein the internal circuit element films are disposed so as to form internal electrodes arranged to provide capacitance between pairs thereof, and the monolithic ceramic electronic component is a monolithic ceramic capacitor.

12. A process for producing a monolithic ceramic electronic component according to claim 1, wherein the ceramic slurry and the ceramic paste each contain a magnetic ceramic powder.

13. A process for producing a monolithic ceramic electronic component according to claim 12, wherein the internal circuit element films are curved conductive films disposed so as to form a monolithic inductor when the green laminate is fired.

6. A process for producing a monolithic ceramic electronic which comprises:

forming a composite structure by shaping the ceramic slurry into a ceramic green sheet having a main surface, applying a conductive paste onto a portion of the main surface of the ceramic green sheet so as to provide step-like section of an internal circuit element film, and applying a ceramic paste onto the region on the main surface of the sheet on which the element film has not been formed so as to form a ceramic green layer which substantially compensates for the spaces defined by the step-like section;

forming a green laminate by laminating a plurality of the composite structures; and

firing the green laminate,

wherein the ceramic paste comprises ceramic powder, an organic solvent and an organic binder, and

wherein the organic binder comprises a copolymer of alkyl (meth) acrylate and a reactive monomer having a carboxyl group, an alkylene oxide group, a hydroxyl group, a glycidyl group, an amino group or an amido group.

14. A process for producing a monolithic ceramic electronic component according to claim 6, further comprising preparing the ceramic paste by

dispersing a first mixture comprising ceramic powder and a first organic solvent in the absence of organic binder to provide a primary dispersion;

dispersing a second mixture comprising organic binder and the primary dispersion to provide a secondary dispersion; and

removing the first organic solvent from the secondary dispersion by heating the secondary dispersion,

wherein a second organic solvent having a relative evaporation rate lower than that of the first organic solvent is incorporated into the first mixture or the second mixture or both.

15. A process for producing a monolithic ceramic electronic component according to claim 14, wherein the ceramic slurry and the ceramic paste each contain a ceramic powder of substantially the same composition;

the binder copolymer has a molecular weight of about 1,000 to 300,000 and contains at least about 50 mol % alkyl (meth) acrylate;

the amount of binder is about 1 to 20 wt. % based on the ceramic;

the first organic solvent has a relative evaporation rate of at least 100; and

the second organic solvent has a relative evaporation rate of less than about 50 and a boiling point of at least about 150°

C.

16. A process for producing a monolithic ceramic electronic component according to claim 15, wherein the binder copolymer has a molecular weight of about 10,000 to 100,000;

the amount of binder is about 3 to 10 wt. % based on the ceramic; and

the second organic solvent has a boiling point of about 200 to 250°

C.

17. A process for producing a monolithic ceramic electronic component according to claim 6, wherein the ceramic slurry and the ceramic paste each contain a ceramic powder of substantially the same composition.

18. A process for producing a monolithic ceramic electronic component according to claim 6, wherein the ceramic slurry and the ceramic paste each contain a dielectric ceramic powder.

19. A process for producing a monolithic ceramic electronic component according to claim 18, wherein the internal circuit element films are disposed so as to form internal electrodes arranged to provide capacitance between pairs thereof, and the monolithic ceramic electronic component is a monolithic ceramic capacitor.

20. A process for producing a monolithic ceramic electronic component according to claim 6, wherein the ceramic slurry and the ceramic paste each contain a magnetic ceramic powder.

21. A process for producing a monolithic ceramic electronic component according to claim 20 wherein the internal circuit element films are curved conductive films disposed so as to form a monolithic inductor when the green laminate is fired.