US4961998A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dielectric composition having controlled thermal expansion
Assignee: Vibrantz Corp
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Filing: 1989-02-10
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Granted: 1990-10-09
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Expires: 2009-02-10
Abstract
Abstract Dielectric ink, paste and tape compositions having controlled thermal expansion contain a mixture of glasses wherein at least one glass has a coefficient of thermal expansion (CTE) below the CTE of the substrate to which the dielectric composition is applied and at least one glass has a CTE above the CTE of said substrate. The dielectric compositions significantly reduce or eliminate warpage of the substrate.
Inventors
- 👤 Robert E. Senkalski
- 👤 Donald L. Hasenmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:28
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/14; C; C03; C03C; C03C3/00; C03C3/04; C03C3/062; C03C3/064; C03C3/066; C03C3/076; C03C3/089; C03C3/091; C03C3/093; C04; C04B; C04B41/00; C04B41/45; C04B41/50; C04B41/5022; H; H01; H01B; H01B3/00; H01B3/02; H01B3/08; H01B3/084; H01B3/085; H01B3/087; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; Y; Y10; Y10S; Y10S428/00; Y10S428/901
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
88 words
A dielectric composition, suitable for casting or laminating onto a ceramic substrate, comprising in combination (a) about 20-65% by weight of a refractory filler, (b) about 10-30% by weight of an organic binder and (c) about 25-60% by weight of a mixture of (i) at least one non-crystalline glass having a coefficient of thermal expansion less than the coefficient of thermal expansion of said substrate and (ii) at least one non-crystalline glass having a coefficient of thermal expansion greater than the coefficient of thermal expansion of said substrate.
Claim 2
Dependent Claim
88 words
A dielectric composition, suitable for casting or laminating onto a ceramic substrate, comprising in combination (a) about 20-65% by weight of a refractory filler, (b) about 10-30% by weight of an organic binder and (c) about 25-60% by weight of a mixture of (i) at least one non-crystalline glass having a coefficient of thermal expansion less than the coefficient of thermal expansion of said substrate and (ii) at least one non-crystalline glass having a coefficient of thermal expansion greater than the coefficient of thermal expansion of said substrate.
Claim 3
Dependent Claim
22 words
A composition of claim 1 wherein said substrate is selected from the group consisting of alumina, aluminum nitride, beryllia and silicon carbide.
Claim 4
Dependent Claim
13 words
A composition of claim 2 wherein said substrate comprises 96% by weight alumina.
Claim 5
Dependent Claim
27 words
A composition of claim 3 wherein said substrate has a coefficient of thermal expansion from about 7.5×10°-6/°C. to about 7.9×10°-6/°C. over a temperature of about 25°-900° C.
Claim 6
Dependent Claim
24 words
A composition of claim 1 wherein the weight ratio of said glass (i) to said glass (ii) ranges from about 10:90 to about 90:10.
Claim 7
Dependent Claim
24 words
A composition of claim 1 wherein the weight ratio of said glass (i) to said glass (ii) ranges from about 25:75 to about 75:25.
Claim 8
Dependent Claim
12 words
A composition of claim 1 wherein said glass is a borosilicate glass.
Claim 9
Dependent Claim
51 words
A composition of claim 3 wherein said glass (i) has a coefficient of thermal expansion of about 6.77×10°-6 per °C. over a temperature range of about 25°-250° C. and said glass (ii) has a coefficient of thermal expansion of about 8.0×10°-6 per °C. over a temperature range of about 25°-250° C.
Claim 10
Dependent Claim
33 words
A composition of claim 3 wherein said glass (i) comprises by weight about 22.8% SiO 2 , 29.5% B 2 O 3 , 1.5% Co 2 O 3 38.3% BaO and 7.9% ZnO.
Claim 11
Dependent Claim
49 words
A composition of claim 3 wherein said glass (i) comprises by weight 100 parts Si, 73.9 parts Ca, 62.8 parts Zn, 17.4 parts Al, 10.1 parts Ti, 7.3 parts K, 14.0 parts Zr, 6.6 parts Pb, 6.0 parts Mn, 3.7 parts Sn, 3.1 parts P and 2.4 parts Rb.
Claim 12
Dependent Claim
42 words
A composition of claim 3 wherein said glass (ii) comprises by weight about 52.3% SiO 2 , 15.4% B 2 O 3 , 4.1% Al 2 O 3 , 4.3% Na 2 O, 5.4% CaO, 17.3% SrO and 1.2% ZrO 2 .
Claim 13
Dependent Claim
41 words
A composition of claim 3 wherein said glass (ii) comprises by weight about 15.0% SiO 2 , 26.7% B 2 O 3 , 3.0% Al 2 O 3 , 50.2% BaO, 2.1% Bi 2 O 3 and 3.0% TiO 2 .
Claim 14
Dependent Claim
41 words
In a process for fabricating an electronic circuit board, the improvement comprising applying a layer of the composition of claim 1 onto a rigid ceramic substrate and firing said substrate at a temperature of about 800° C. to about 1000° C.
Claim 15
Dependent Claim
11 words
A ceramic substrate containing cast thereon a composition of claim 1.
Claim 16
Dependent Claim
21 words
A composition of claim 1 wherein said composition is a paste having a viscosity of about 100,000 to about 400,000 centipoise.
Claim 17
Dependent Claim
20 words
A composition of claim 15 wherein said composition has been further diluted with an organic solvent to a flowable dispersion.
Claim 18
Dependent Claim
12 words
A composition of claim 1 wherein said composition is a solid film.
Claim 19
Dependent Claim
15 words
A composition of claim 17 wherein said composition has been applied onto a polymeric film.
Claim 20
Dependent Claim
11 words
A composition of claim 18 wherein said polymeric film is polyester.
Claim 21
Dependent Claim
27 words
A composition of claim 17 comprising by weight about 39.3% of said glass mixture about 45.2% of said refractory filler and about 15.5% of said organic binder.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-10-08 | 1994-04-09 | 1994-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-08 | 1998-04-09 | 1998-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-08 | 2002-04-09 | 2002-10-09 | $7700.00 | Window Closed / Lapsed |