Patent US4935844A successfully refreshed from Google Patents.
US4935844A
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US
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Low dielectric constant compositions
Assignee: Individual
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Filing: 1989-10-19
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Granted: 1990-06-19
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Expires: 2009-10-19
Abstract
Abstract An alkali-free composition for making a ceramic dielectric body having a dielectric constant less than 5.0, which is a mixture of finely divided particles consisting essentially of 70-85% wt. slica and 15-30% wt. zinc borate flux. This composition can be used to make green tape and multilayer devices having internal copper conductors such as multilayer capacitors and multilayer interconnects.
Inventors
- 👤 Ian Burn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:26
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/005; H01G4/008; H01G4/0085; B; B22; B22F; B22F1/00; B22F1/10; B28; B28B; B28B1/00; B28B1/002; B28B23/00; B32; B32B; B32B18/00; C; C04; C04B; C04B41/00; C04B41/45; C04B41/50; C04B41/51; C04B41/5127; C04B41/5188; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K3/00; H05K3/46; H05K3/4644; H05K3/4664; H05K3/4667; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H10W70/098; C04B2235/00; C04B2235/65; C04B2235/656; C04B2235/6567; C04B2235/658; C04B2235/6583; C04B2235/6584; C04B2237/00; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/341; C04B2237/50; C04B2237/68; C04B2237/70; C04B2237/704; H05K1/09; H05K1/092; H05K2203/00; H05K2203/08; H05K2203/086; H05K2203/11; H05K2203/1126; H05K3/10; H05K3/12; H05K3/1283; H05K3/1291; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12903
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
58 words
A dielectric green tape for forming a ceramic dielectric body having a dielectric constant less than 5.0 comprising a layer of a composition comprising an alkali-free mixture of finely divided particles consisting essentially of: (a) 70-85% by weight silica particles and (b) 15-30% by weight zinc borate flux particles dispersed in an organic medium comprising a polymeric binder.
Claim 2
Dependent Claim
58 words
A dielectric green tape for forming a ceramic dielectric body having a dielectric constant less than 5.0 comprising a layer of a composition comprising an alkali-free mixture of finely divided particles consisting essentially of: (a) 70-85% by weight silica particles and (b) 15-30% by weight zinc borate flux particles dispersed in an organic medium comprising a polymeric binder.
Claim 3
Dependent Claim
38 words
The dielectric green tape of claim 1 wherein the zinc borate flux consists essentially of zinc oxide and boron oxide and the mole ratio of zinc oxice to boron oxide is in the range of 3/1 to 1/1.
Claim 4
Dependent Claim
24 words
The dielectric green tape of claim 2 wherein the mole ratio of zinc oxide to boron oxide is 2/1 in the zinc borate flux.
Claim 5
Dependent Claim
12 words
The dielectric green tape of claim 1 wherein the silica is alpha-quartz.
Claim 6
Dependent Claim
28 words
The dielectric green tape of claim 1 wherein the formed ceramic dielectric body has a thermal coefficient of expansion in the range of 1.5 to 8.5 ppm/° C.
Claim 7
Dependent Claim
57 words
A multilayer capacitor comprising a plurality of layers of the green tape of claim 1 having a printed thick film copper electrode layer therebetween, the multilayer capacitor having been fired in an atmosphere having a low oxygen content to effect volatilization of the organic medium, sintering and densification of the alkali free mixture of finely divided particles.
Claim 8
Dependent Claim
37 words
The multilayer capacitor of claim 6 wherein the zinc borate flux consists essentially of zinc oxide and boron oxide and the mole ratio of zinc oxice to boron oxide is in the range of 3/1 to 1/1.
Claim 9
Dependent Claim
23 words
The multilayer capacitor of claim 7 wherein the mole ratio of zinc oxide to boron oxide is 2/1 in the zinc borate flux.
Claim 10
Dependent Claim
11 words
The multilayer capacitor of claim 6 wherein the silica is alpha-quartz.
Claim 11
Dependent Claim
25 words
The multilayer capacitor of claim 6 wherein the dielectric layers have a thermal coefficient of expansion in the range of 1.5 to 8.5 ppm/° C.
Claim 12
Dependent Claim
56 words
A multilayer ceramic substrate comprising a plurality of layers of the green tape of claim 1 having interconnected copper conductor layers therebetween, the multilayer ceramic substrate having been fired in an atmosphere having a low oxygen content to effect volatilization of the organic medium, sintering and densification of the alkali free mixture of finely divided particles.
Claim 13
Dependent Claim
35 words
The multilayer ceramic substrate of claim 11 wherein the zinc borate flux consists essentially of zinc oxide and boron oxide and the mole ratio of zinc oxide is in the range of 3/1 to 1/1.
Claim 14
Dependent Claim
24 words
The multilayer ceramic substrate of claim 12 wherein the mole ratio of zinc oxide to boron oxide is 2/1 in the zinc borate flux.
Claim 15
Dependent Claim
12 words
The multilayer ceramic substrate of claim 11 wherein the silica is alpha-quartz.
Claim 16
Dependent Claim
25 words
The multilayer ceramic substrate of claim 11 wherein the dielectric layers have a thermal coefficient of expansion in the range of 1.5 to 8.5 ppm/°C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |