US5296189A
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US
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Method for producing metal powder with a uniform distribution of dispersants, method of uses thereof and structures fabricated therewith
Assignee: International Business Machines Corp
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Filing: 1992-04-28
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Granted: 1994-03-22
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Expires: 2012-04-28
Abstract
Abstract Methods of fabricating powders of metal particles containing grain growth control additives are described. A powder, metal particles, e.g., copper particles, are mixed with a powder of additive particles, e.g., alumina particles. The mixture is milled in a high energy ball mill to provide metal particles having substantially uniformly distributed therein of additive particles. The ball milled powder contains elongated high aspect ratio particles. The high aspect ratio particles are reduced in size by jet impact milling. The jet impact milled powder can be used to form a conductor forming paste in the fabrication of a metallized ceramic substrate for semiconductor chip packaging application. The jet impact milled powder has particles of sufficiently small in size to fill vias between metallization layers in the green ceramic precursor to the ceramic substrate. During sintering of the combination of ceramic precursor and conductor forming paste, the grain growth control additive results in a substantially void free via filled with metal having a fine grain morphology.
Inventors
- 👤 Sung K. Kang
- 👤 Sampath Purushothaman
- 👤 John J. Ritsko
- 👤 Jane M. Shaw
- 👤 Subhash L. Shinde
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:46
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/09; H05K1/092; B; B22; B22F; B22F9/00; B22F9/02; B22F9/04; C; C22; C22C; C22C1/00; C22C1/10; C22C1/1084; B22F2009/043; B22F2999/00
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
72 words
A method of forming a powder of particles containing a substantially uniform distribution of an additive therein comprising: providing a first powder of particles; providing a second powder of said additive particles; ball milling an admixture of said first powder and said second powder to provide ball milled particles; jet impact milling said ball milled admixtures to form said powder of said particles containing said substantially uniform distribution of said additive therein.
Claim 2
Independent Claim
72 words
A method of forming a powder of particles containing a substantially uniform distribution of an additive therein comprising: providing a first powder of particles; providing a second powder of said additive particles; ball milling an admixture of said first powder and said second powder to provide ball milled particles; jet impact milling said ball milled admixtures to form said powder of said particles containing said substantially uniform distribution of said additive therein.
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein said ball milling is high energy ball milling.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein said additive is a grain growth control additive.
Claim 5
Dependent Claim
45 words
The method of claim 1, wherein said jet impact milling comprises: providing a first and second stream of said ball milled particle admixture; directing said first stream at said second stream so that particles in said first stream collide with particles in said second stream.
Claim 6
Dependent Claim
15 words
The method of claim 4, wherein said jet impact milling fractures said ball milled particles.
Claim 7
Dependent Claim
17 words
The method of claim 1, wherein said first powder of particles is a powder of metal particles.
Claim 8
Dependent Claim
27 words
The method of claim 1, wherein said additives are particles selected from the group consisting of particles of alumina, yttria, thoria, titania or other refractory metal oxides.
Claim 9
Dependent Claim
23 words
The method of claim 1, wherein said particles of said first powder have a size from about 2 microns to about 5 microns.
Claim 10
Dependent Claim
20 words
The method of claim 1, wherein said additive particles have a size from about 0.05 microns to about 0.1 microns.
Claim 11
Dependent Claim
20 words
The method of claim 1, wherein said admixture of said first powder and said second powder further includes a solvent.
Claim 12
Dependent Claim
20 words
The method of claim 10, wherein said solvent is selected from the group consisting of ethyl alcohol or methyl alcohol.
Claim 13
Dependent Claim
16 words
The method of claim 1, wherein said powder of particles is an electrical conductor forming composition.
Claim 14
Dependent Claim
17 words
The method of claim 1, further including screening said powder to screen out particles of preselected size.
Claim 15
Dependent Claim
12 words
The method of claim 6, wherein said metal particles are copper particles.
Claim 16
Dependent Claim
134 words
The method of claim 12, further comprising; forming at least one green sheet comprised of a binder having dispersed therein particles selected from the group consisting of particles of glass and an admixture of glass particles and crystalline particles, said green sheet having a sintering temperature below the melting point of said electrical conductors; forming on a surface of said first green sheet a pattern of said conductor forming composition, superimposing a second said sheet on said surface of said first sheet to sandwich said pattern therebetween; laminating said superimposed sheets together to form a laminate; heating said laminate to a burn-out temperature and maintaining said laminate thereat for sufficient time to decompose and eliminate said binder; and sintering said laminate to form a ceramic structure having electrical conductors extending within the interior thereof.
Claim 17
Dependent Claim
18 words
The method of claim 15, wherein said burn-out temperature is from about 160° C. to about 450° C.
Claim 18
Dependent Claim
35 words
The method of claim 15, where said crystalline particles are selected from the group consisting of cordierite, spodument, eucryptite, enstatite, celsian, wollastinite, willemite, anorthite, lithium disilicate, lithium metasilicate, mullite, aluminum nitride, alumina and combinations thereof.
Claim 19
Dependent Claim
41 words
The method of claim 15, wherein said glass is selected from the group consisting of borosilicate glass, lead glass and precursors to cordierite, spodumene, eucryptite, enstatite, celsian, wollastinite, willemite, anorthite, lithium disilicate, lithium metasilicate, mullite, aluminum nitride, alumina and combinations thereof.
Claim 20
Dependent Claim
20 words
The method of claim 15, including providing means for extending said pattern to at least one surface of said laminate.
Claim 21
Dependent Claim
16 words
The method of claim 15, wherein said laminate is sintered in a reducing or inert atmosphere.
Claim 22
Dependent Claim
24 words
The method of claim 18, including mounting an integrated semiconductor chip on said surface in electrical connection to a portion of said pattern extension.
Claim 23
Dependent Claim
14 words
The method of claim 15, wherein said conductor forming composition further includes a binder.
Claim 24
Dependent Claim
20 words
The method of claim 15, wherein said glass is selected from the group consisting of crystallizable glass and uncrystallizable glass.
Claim 25
Dependent Claim
39 words
The method of claim 12, further comprising; forming a body of a green precursor to a ceramic material; said body containing patterns of said electrical conductor forming composition; firing said body to form a ceramic containing electrical conductors therein.
Claim 26
Dependent Claim
14 words
The method of claim 1, wherein said additive particles control thermal coefficient of expansion.
Claim 27
Dependent Claim
12 words
The method of claim 1, wherein said additive particles control electrical conductivity.
Claim 28
Dependent Claim
12 words
The method of claim 1, wherein said additive particles control fracture toughness.
Claim 29
Dependent Claim
12 words
The method of claim 1, wherein said additive particles control flexural strength.
References Cited (Backward Citations)
US1792262A
Cited
US3070436A
Cited
US3166416A
Cited
US3192042A
Cited
US3218135A
Cited
US3143789A
Cited
US4090874A
Cited
US4398969A
Cited
US4609525A
Cited
US4443249A
Cited
US4557893A
Cited
US4599119A
Cited
US4594181A
Cited
US4600604A
Cited
US4891059A
Cited
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