WO1993006053A1 - Substrat a faible constante dielectrique et procede de fabrication - Google Patents

Substrat a faible constante dielectrique et procede de fabrication Download PDF

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Publication number
WO1993006053A1
WO1993006053A1 PCT/US1991/009751 US9109751W WO9306053A1 WO 1993006053 A1 WO1993006053 A1 WO 1993006053A1 US 9109751 W US9109751 W US 9109751W WO 9306053 A1 WO9306053 A1 WO 9306053A1
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WO
WIPO (PCT)
Prior art keywords
substrate
ceramic particles
glass
weight percent
less
Prior art date
Application number
PCT/US1991/009751
Other languages
English (en)
Inventor
Lawrence Daniel David
Sarah Huffsmith Knickerbocker
Original Assignee
International Business Machines Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Business Machines Corporation filed Critical International Business Machines Corporation
Priority to JP4506167A priority Critical patent/JPH07108832B2/ja
Priority to EP92906259A priority patent/EP0605421A1/fr
Publication of WO1993006053A1 publication Critical patent/WO1993006053A1/fr

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/12—Mountings, e.g. non-detachable insulating substrates
    • H01L23/14—Mountings, e.g. non-detachable insulating substrates characterised by the material or its electrical properties
    • H01L23/15—Ceramic or glass substrates
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C14/00—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix
    • C03C14/002—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix the non-glass component being in the form of fibres, filaments, yarns, felts or woven material
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C14/00—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix
    • C03C14/004—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix the non-glass component being in the form of particles or flakes
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/03—Use of materials for the substrate
    • H05K1/0306—Inorganic insulating substrates, e.g. ceramic, glass
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2214/00—Nature of the non-vitreous component
    • C03C2214/02—Fibres; Filaments; Yarns; Felts; Woven material
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2214/00—Nature of the non-vitreous component
    • C03C2214/04—Particles; Flakes
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2214/00—Nature of the non-vitreous component
    • C03C2214/06—Whiskers ss
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2214/00—Nature of the non-vitreous component
    • C03C2214/32—Nature of the non-vitreous component comprising a sol-gel process
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/095—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00 with a principal constituent of the material being a combination of two or more materials provided in the groups H01L2924/013 - H01L2924/0715
    • H01L2924/097—Glass-ceramics, e.g. devitrified glass
    • H01L2924/09701—Low temperature co-fired ceramic [LTCC]

Definitions

  • This invention relates to glass and/or ceramic (hereinafter just ceramic) substrates, and more particularly relates to ceramic substrates useful for electronics packaging and to a method for making such substrates.
  • Ceramic structures are used in the production of electronic substrates and devices. Many different types of structures can be used, and a few of these structures are described below.
  • a multilayered ceramic circuit substrate may comprise patterned metal layers which act as electrical conductors sandwiched between ceramic layers which act as insulators.
  • the substrates may be designed with termination pads for attaching semiconductor chips, connector leads, capacitors, resistors, covers, etc. Interconnection between buried conductor levels can be achieved through vias formed by metal paste-filled holes in the individual ceramic layers formed prior to lamination, which, upon sintering will become a sintered dense metal interconnection of metal-based conductor.
  • conventional ceramic structures are formed from ceramic green sheets which are prepared by mixing a ceramic particulate, a catalyst (e.g., such as that disclosed in Herron et al. U.S. Patent 4,627,160), a thermoplastic polymeric binder, -2- plasticizers, and solvents. This composition is spread or cast into ceramic sheets or slips from which the solvents are subsequently volatilized to provide coherent and self-supporting flexible green sheets. After blanking, stacking, and laminating, the green sheets are eventually fired at temperatures sufficient to drive off the polymeric binder resin and sinter the ceramic particulates together into a densified ceramic substrate.
  • a catalyst e.g., such as that disclosed in Herron et al. U.S. Patent 4,627,160
  • -2- plasticizers e.g., such as that disclosed in Herron et al. U.S. Patent 4,627,160
  • solvents e.g., such as that disclosed in Herron et al. U.S. Patent
  • the electrical conductors used in formation of the electronic substrate may be high melting point metals such as molybdenum and tungsten or a noble metal such as gold. It is more desirable, however, to use a conductor having a low electrical resistance and low cost, such as copper and alloys thereof.
  • Present state-of-the-art ceramic substrates are made from cordierite glass-ceramic particulate materials such as that disclosed in Kumar et al.
  • alumina Prior to the cordierite glass-ceramic materials, alumina for a number of years had been an adequate dielectric material for microelectronic packaging. Alumina, however, has a dielectric constant approaching 10 which causes high signal propagation delay and low signal-to-noise ratio. Further, alumina has a TCE about twice as high as- silicon which impacts the silicon chip to ceramic thermal fatigue resistance.
  • Porous silica films have been formed which have a dielectric constant as low as 1. This material is not expected to be suitable for electronic packaging because of shrinkage on firing, insufficient mechanical integrity of the resulting structures, and thermal expansion mismatch with silicon.
  • a possible successor material of interest is a ceramic comprised of silica and borosilicate glass.
  • a ceramic comprised of silica and borosilicate glass.
  • Tosaki et al. U.S. Patent 4,547,625 and Kokuleu et al.
  • U. S. Patent 4,624,934 disclose mixtures of a borosilicate glass and silica glass or refractory particles. These mixtures are made by ball-milling the components together. The resulting products have dielectric constants of 4.05 or greater.
  • Non-Crystalline Solids 100, pp. 501-505 (1988) have proposed the patterning of silica and borosilicate glass films on glass substrates. The films are patterned by a mechanical stamper while the films are in the gel state.
  • the borosilicate glasses disclosed include, in addition to silica and boron oxide, magnesia, calcia, and alumina. These additional components are added to the glass for a number of reasons. Included among these reasons are the need for chemical stability of the glass and the desire that the ceramic particles not react excessively with the glass. Unfortunately, adding magnesia, calcia, and alumina also raises the dielectric constant of the glass. As noted in the
  • the objects of the invention have been achieved by providing a low dielectric constant substrate which comprises ceramic particles uniformly coated with a borosilicate glass.
  • a low dielectric constant substrate which comprises ceramic particles uniformly coated with a borosilicate glass.
  • the resulting ceramic substrate preferably has a dielectric constant of about 4 or less.
  • Figures 1A and IB are schematical representations before and after sintering, respectively, of a borosilicate glass/ceramic particle composition prepared by a conventional ball-milling technique.
  • Figures 2A and 2B are schematical representations before and after sintering, respectively, of a borosilicate glass/ceramic particle composition prepared by a sol-gel technique.
  • Figure 3 is a graph of percent theoretical density versus percent borosilicate glass coating on silica ceramic particles.
  • a low dielectric constant substrate comprising ceramic particles uniformly coated with a borosilicate glass where the substrate has a dielectric constant of about 4 or less.
  • the dielectric constant is a function of the composition of the borosilicate glass, the percent of borosilicate glass coating the ceramic particles, and the composition of the ceramic particles.
  • the uniform coating of the ceramic particles is a distinguishing characteristic resulting from their prior sol-gel processing.
  • the fact that ceramic particles coated by a sol-gel process can be so readily identified is made apparent by a comparison of Figures 1 and 2.
  • Figure 1 a ceramic mixture is schematically illustrated after being prepared by a conventional ball-milling technique.
  • the ceramic particles are mixed with borosilicate glass particles prior to sintering.
  • the borosilicate glass has formed irregularly shaped globules cementing the ceramic particles together. Note that there is little, if any, coating of the ceramic particles by the glass.
  • Figures 2A and 2B also schematically illustrate ceramic mixtures prior to and after sintering, respectively.
  • the ceramic mixture prior to sintering has been prepared by a sol-gel process.
  • the ceramic particles have been coated with a borosilicate glass. The coating appears uniform which shall mean that the coating is evenly distributed around the periphery of the ceramic particles.
  • the borosilicate glass coating on the ceramic particles appears intact and uniform even where there is particle to particle bonding. Note the absence of borosilicate globules which can cause distortion.
  • the glass comprises 10 to 50 volume percent of the substrate with the remainder being made up by the ceramic particles.
  • the borosilicate glass is made up of 10 to 30 weight percent boron oxide with the remainder being silica (Si0 2 ).
  • silica Si0 2
  • no additional compounds should be added to the boron oxide and silica. It has been found that the best properties are obtained when boron oxide and silica are the essential components of the borosilicate glass. It is, of course, possible that applications of the present invention may require additional properties not important here, for example, lowered melting point.
  • magnesia, calcia, and/or alumina and/or other components should amount to no more than about 20 weight percent of the glass, more preferably about 10 weight percent or less, while the amount of boron oxide should remain in the range of 10 to 30 weight percent.
  • the preferred ceramic particles are silica and cordierite for lowest dielectric constant
  • other ceramic particles may be added to or instead of the silica and/or cordierite to the ceramic mixture to obtain the desired properties.
  • these other ceramic particles may include alumina, spodumene, mullite, enstatite, forsterite, spinel, beta-eucryptite, anorthite, aluminum nitride, silicon nitride, and mixtures thereof.
  • Porous substrates are advantageous in that they have a lower dielectric constant than fully dense substrates .
  • porous substrates often suffer from poor mechanical integrity.
  • the present inventors have found, however, that mechanically strong, porous substrates may be made by regulating the amount of -borosilicate glass that coats the ceramic particles.
  • the substrates according to the invention are made by the following process:
  • (a) coating the ceramic particles with- a borosilicate glass by a sol-gel process consists of hydrolyzing a boron oxide precursor with a silica precursor in a solvent or solvent mixture, mixing this solution with the ceramic particles and then stripping the solvent or solvent mixture from the ceramic particles.
  • a convenient stripping process is drying the particles in an oven or on a hot plate at low temperature.
  • the glass mixture and ceramic particles chosen are selected to meet the electrical and mechanical requirements of the resulting substrate.
  • a low dielectric constant preferably about 4 or less
  • the substrate is by the tape casting method.
  • the coated particles are mixed with a suitable solvent or solvents and a binder material to form a slurry.
  • binders include
  • the substrate 25 has copper (preferred because of its low resistivity) wiring patterns, then a protective atmosphere has to be used to sinter the substrate and burn out the organic residues while avoiding oxidation 30 of the copper. Additionally, because copper melts at 1083°C, the substrate should be able to be sintered at a temperature less than about 1000°C.
  • a ceramic material consisting of 10 weight percent borosilicate glass (20 weight percent B 2 0 3 , 80 weight percent Si0 2 ) and 90 weight percent silica particles was made in the following manner:
  • TEOS TEOS
  • HCl HCl
  • 34 milliliters (0.2 mole) of triethylborate was added to the slurry, which was further stirred overnight.
  • the slurry was then poured into a flat tray and warmed gently on a hot plate to drive off all of the solvents. The powder was subsequently broken up in a Pulverisette 2 grinding mill.
  • pellet samples for ceramics having 10 weight percent and 30 weight percent B 2 0 3 in the borosilicate glass were prepared. With these samples as well, the percent of the glass coating on the silica particles was varied.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • General Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Power Engineering (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

Substrat à faible constante diélectrique comprenant des particules céramiques enrobées de manière uniforme d'un verre de borosilicate. Le substrat présente de préférence une constante diélectrique inférieure ou égale à 4 environ. On décrit également un procédé de fabrication du substrat à faible constante diélectrique dont un des aspects principaux consiste à enrober des particules céramiques du verre de borosilicate selon un procédé sol-gel.
PCT/US1991/009751 1991-09-26 1991-12-27 Substrat a faible constante dielectrique et procede de fabrication WO1993006053A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP4506167A JPH07108832B2 (ja) 1991-09-26 1991-12-27 低誘電率基板およびその製法
EP92906259A EP0605421A1 (fr) 1991-09-26 1991-12-27 Substrat a faible constante dielectrique et procede de fabrication

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US76572991A 1991-09-26 1991-09-26
US765,729 1991-09-26

Publications (1)

Publication Number Publication Date
WO1993006053A1 true WO1993006053A1 (fr) 1993-04-01

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EP (1) EP0605421A1 (fr)
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0697725A3 (fr) * 1994-08-19 1997-02-19 Hitachi Ltd Composition céramique pour substrat de circuit et méthode de fabrication
EP0975464A1 (fr) * 1997-03-21 2000-02-02 Electro-Science Laboratories, Inc. Compositions de revetement de nitrure de silicium
US6762141B2 (en) * 2000-03-13 2004-07-13 Siemens Aktiengesellschaft Ceramic mass, method for the production of a ceramic mass and use of a ceramic mass
WO2011115953A1 (fr) * 2010-03-15 2011-09-22 Ppg Industries Ohio, Inc. Dispersions de particules encapsulées et leurs procédés de production et d'utilisation
CN103553559A (zh) * 2013-10-17 2014-02-05 天津大学 CaO-B2O3-SiO2玻璃+氮化铝陶瓷的复合材料及制备方法
US11939268B2 (en) 2019-12-31 2024-03-26 Industrial Technology Research Institute Low-k material and method for manufacturing the same

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0234896A2 (fr) * 1986-02-28 1987-09-02 Digital Equipment Corporation Dispositifs microélectroniques et procédés pour leur fabrication
EP0275652A1 (fr) * 1986-12-19 1988-07-27 Corning Glass Works Article céramique composite et son procédé de fabrication
WO1989001461A1 (fr) * 1987-08-13 1989-02-23 Ceramics Process Systems Corporation Boitiers en metal/ceramique conjointement frittables et materiaux utilises pour leur fabrication
EP0326093A2 (fr) * 1988-01-28 1989-08-02 E.I. Du Pont De Nemours And Company Compostion diélectrique
WO1991013042A1 (fr) * 1990-02-28 1991-09-05 E.I. Du Pont De Nemours And Company Composition dielectrique a base de ceramique amelioree et procede de preparation associe

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0234896A2 (fr) * 1986-02-28 1987-09-02 Digital Equipment Corporation Dispositifs microélectroniques et procédés pour leur fabrication
EP0275652A1 (fr) * 1986-12-19 1988-07-27 Corning Glass Works Article céramique composite et son procédé de fabrication
WO1989001461A1 (fr) * 1987-08-13 1989-02-23 Ceramics Process Systems Corporation Boitiers en metal/ceramique conjointement frittables et materiaux utilises pour leur fabrication
EP0326093A2 (fr) * 1988-01-28 1989-08-02 E.I. Du Pont De Nemours And Company Compostion diélectrique
WO1991013042A1 (fr) * 1990-02-28 1991-09-05 E.I. Du Pont De Nemours And Company Composition dielectrique a base de ceramique amelioree et procede de preparation associe

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0697725A3 (fr) * 1994-08-19 1997-02-19 Hitachi Ltd Composition céramique pour substrat de circuit et méthode de fabrication
US5825632A (en) * 1994-08-19 1998-10-20 Hitachi, Ltd. Circuit substrate and electronics computer, using sintered glass ceramics
US6118671A (en) * 1994-08-19 2000-09-12 Hitachi, Ltd. Circuit substrate and manufacture thereof, ceramic composition for circuit substrate, and electronics computer
EP0975464A1 (fr) * 1997-03-21 2000-02-02 Electro-Science Laboratories, Inc. Compositions de revetement de nitrure de silicium
EP0975464A4 (fr) * 1997-03-21 2000-04-12 Electro Science Lab Inc Compositions de revetement de nitrure de silicium
US6214754B1 (en) 1997-03-21 2001-04-10 Electro-Science Laboratories, Inc. Silicon nitride coating compositions
US6762141B2 (en) * 2000-03-13 2004-07-13 Siemens Aktiengesellschaft Ceramic mass, method for the production of a ceramic mass and use of a ceramic mass
WO2011115953A1 (fr) * 2010-03-15 2011-09-22 Ppg Industries Ohio, Inc. Dispersions de particules encapsulées et leurs procédés de production et d'utilisation
CN103553559A (zh) * 2013-10-17 2014-02-05 天津大学 CaO-B2O3-SiO2玻璃+氮化铝陶瓷的复合材料及制备方法
US11939268B2 (en) 2019-12-31 2024-03-26 Industrial Technology Research Institute Low-k material and method for manufacturing the same

Also Published As

Publication number Publication date
JPH07108832B2 (ja) 1995-11-22
EP0605421A1 (fr) 1994-07-13
JPH07502245A (ja) 1995-03-09

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