Patent US2921669A successfully refreshed from Google Patents.
Patent US4604496A successfully refreshed from Google Patents.
US4604496A
Expired / Lapsed
US
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Ceramic multilayer wiring board
Assignee: Hitachi Ltd
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Filing: 1984-08-14
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Granted: 1986-08-05
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Expires: 2004-08-14
Abstract
Abstract A ceramic multilayer wiring board is provided in which ceramic insulating layers and wiring patterns provided thereon are connected by conductors filling through-holes formed in the ceramic insulating layers. The through-holes are so formed that the superficial portions of each through-hole of the ceramic multilayer wiring board is smaller in diameter than the inside portion of the through-hole between the superficial portion. This can prevent the board from being cracked around the through-holes.
Inventors
- 👤 Shosaku Ishihara
- 👤 Takashi Kuroki
- 👤 Gyozo Toda
- 👤 Akio Yasukawa
- 👤 Tatsuji Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:39
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/40; H05K3/42; H05K3/4038; H05K3/4053; H05K3/4061; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K1/09; H05K1/092; H05K2201/00; H05K2201/01; H05K2201/0183; H05K2201/0191; H05K2201/09; H05K2201/09209; H05K2201/095; H05K2201/096; H05K2201/09818; H05K2201/09845; H05K3/46; H05K3/4611; H05K3/4626; H05K3/4629
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
120 words
In a ceramic multilayer wiring board having ceramic insulating layers and wiring patterns provided thereon, said wiring patterns being connected through said ceramic insulating layers by conductors filling a plurality of through-holes formed on said ceramic insulating layers, the improvement in which each of the through-holes range from 0.103 to 0.26 mm in diameter at the superficial portions thereof located at both sides of said ceramic multilayer wiring board, the space between adjacent superficial portions of the through-holes ranges from 0.2 to 1 mm, and the depth of the superficial portions of the through-holes is 0.1 mm or more; said superficial portions of the through-holes being smaller in diameter than inside portions of the through-holes arranged between said superficial portions.
Claim 2
Dependent Claim
120 words
In a ceramic multilayer wiring board having ceramic insulating layers and wiring patterns provided thereon, said wiring patterns being connected through said ceramic insulating layers by conductors filling a plurality of through-holes formed on said ceramic insulating layers, the improvement in which each of the through-holes range from 0.103 to 0.26 mm in diameter at the superficial portions thereof located at both sides of said ceramic multilayer wiring board, the space between adjacent superficial portions of the through-holes ranges from 0.2 to 1 mm, and the depth of the superficial portions of the through-holes is 0.1 mm or more; said superficial portions of the through-holes being smaller in diameter than inside portions of the through-holes arranged between said superficial portions.
Claim 3
Dependent Claim
48 words
A ceramic multilayer wiring board according to claim 1 wherein outermost ceramic insulating layers define the superficial portions of the through-holes and each have a thickness that is smaller than the thicknesses of the insulating layers defining the inside portions of the through-holes arranged between the superficial portions.
Claim 4
Dependent Claim
41 words
A ceramic multilayer wiring board according to claim 2 wherein the superficial portions of the through-holes extend through each of the outermost ceramic layers and occurrence of cracks in the areas of the ceramic layers surrounding the superficial portions is prevented.
Claim 5
Dependent Claim
31 words
A ceramic multilayer wiring board according to claim 1, wherein the through-hole diameter of the superficial portions is 0.103 mm or less when the space between the through-holes is 0.2 mm.
Claim 6
Dependent Claim
27 words
A ceramic multilayer wiring board according to claim 1, wherein the through-hole diameter is 0.145 mm or less when the space between the through-holes is 0.5 mm.
Claim 7
Dependent Claim
31 words
A ceramic multilayer wiring board according to claim 1, wherein the through-hole diameter of the superficial portions is 0.268 mm or less when the space between the through-holes is 1 mm.
References Cited (Backward Citations)
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Cited
US3561110A
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US4237606A
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US4336551A
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US4211603A
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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) | 1989-08-04 | 1990-02-03 | 1990-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-04 | 1994-02-03 | 1994-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-04 | 1998-02-03 | 1998-08-05 | $7700.00 | Window Closed / Lapsed |