US4724283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-layer circuit board having a large heat dissipation
Assignee: NEC Corp
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Filing: 1986-09-29
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Granted: 1988-02-09
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Expires: 2006-09-29
Abstract
Abstract A multi-layer circuit board is disclosed which includes a plurality of AlN ceramic layers stocked and combined as an integrated form and wiring layers interposed at different levels between the AlN ceramic layers. The wiring layers are made of a mixture of tungsten and AlN ceramic particles, the content of the AlN ceramic particles being 0.5 to 2.0 wt. %. A plurality of through-holes are formed in the AlN ceramic layers to interconnect the wiring layers formed at different levels.
Inventors
- 👤 Yuzo Shimada
- 👤 Yasuhiro Kurokawa
- 👤 Kazuaki Utsumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:53
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/611; H10W70/67; H10W70/68; H10W70/685; H10W70/69; H10W70/692; H05; H05K; H05K1/00; H05K1/02; H05K1/09; H05K1/092; H05K3/00; H05K3/46; H05K3/4611; H05K3/4626; H05K3/4629
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
58 words
A multi-layer circuit board comprising: a plurality of aluminum nitride ceramic layers; and at least one wiring layer formed between said aluminum nitride ceramic layers, said aluminum nitride ceramic layers and said wiring layer being integrated into a single circuit board, and said wiring layer being made of a mixture of refractory metal and aluminum nitride ceramic particles.
Claim 2
Dependent Claim
58 words
A multi-layer circuit board comprising: a plurality of aluminum nitride ceramic layers; and at least one wiring layer formed between said aluminum nitride ceramic layers, said aluminum nitride ceramic layers and said wiring layer being integrated into a single circuit board, and said wiring layer being made of a mixture of refractory metal and aluminum nitride ceramic particles.
Claim 3
Dependent Claim
26 words
A multi-layer circuit board as claimed in claim 1, wherein at least one of said aluminum nitride ceramic layers has a through-hole filled with said mixture.
Claim 4
Dependent Claim
15 words
A multi-layer circuit board as claimed in claim 2, wherein said refractory metal is tungsten.
Claim 5
Dependent Claim
27 words
A multi-layer circuit board as claimed in claim 3, wherein said aluminum nitride ceramic particles are uniformly distributed in said mixture in 0.5 to 2.0 wt. percent.
Claim 6
Dependent Claim
54 words
A multi-layer circuit board as claimed in claim 4 further comprising a die pad on which a semiconductor chip is to be mounted and a plurality of bonding pads to which bonding wires connected to electrodes on said semiconductor chip are to be bonded, on the surface of an uppermost aluminum nitride ceramic layer.
Claim 7
Dependent Claim
26 words
A multi-layer circuit board as claimed in claim 5, wherein each of said aluminum nitride ceramic layers has a thickness of 10 μm to 400 μm.
Claim 8
Dependent Claim
140 words
A ceramic circuit board comprising: a plurality of ceramic layers stacked and combined as an integrated form having an uppermost layer, said ceramic layers being made of an aluminum nitride ceramic material; wiring layers interposed at different levels between said ceramic layers, said wiring layers being made of a mixture of refractory metal and aluminum ceramic particles of 0.5 to 2.0 wt. percent; through-holes formed in said ceramic layers to interconnect said wiring layers in different levels, said through-holes being filled with said mixture; a die pad formed on the surface of the uppermost ceramic layer; a plurality of bonding pads formed on said surface of said uppermost ceramic layer; and a plurality of additional through-holes formed in said uppermost ceramic layer and filled with said mixture to connect said bonding pads to at least one of said wiring layers.
Claim 9
Dependent Claim
140 words
A ceramic circuit board comprising: a plurality of ceramic layers stacked and combined as an integrated form having an uppermost layer, said ceramic layers being made of an aluminum nitride ceramic material; wiring layers interposed at different levels between said ceramic layers, said wiring layers being made of a mixture of refractory metal and aluminum ceramic particles of 0.5 to 2.0 wt. percent; through-holes formed in said ceramic layers to interconnect said wiring layers in different levels, said through-holes being filled with said mixture; a die pad formed on the surface of the uppermost ceramic layer; a plurality of bonding pads formed on said surface of said uppermost ceramic layer; and a plurality of additional through-holes formed in said uppermost ceramic layer and filled with said mixture to connect said bonding pads to at least one of said wiring layers.
References Cited (Backward Citations)
US3770529A
Cited
US4328531A
Cited
US4336088A
Cited
US4465727A
Cited
US4598167A
Cited
US4578365A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-08 | 1991-08-10 | 1992-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-08 | 1995-08-10 | 1996-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-08 | 1999-08-10 | 2000-02-09 | $7700.00 | Window Closed / Lapsed |