US5506755A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-layer substrate
Assignee: Toshiba Corp
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Filing: 1994-08-18
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Granted: 1996-04-09
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Expires: 2014-08-18
Abstract
Abstract A multi-layer wiring substrate includes an aluminum nitride ceramic substrate, a multi-layer wiring part having an electric insulating layer of an organic polymer, a die pad for mounting thereon an electronic part, and a thermal via of a column shape for effectively dissipating heat generated in the mounted electric part. The multi-layer wiring part is integrally formed on the ceramic substrate. The die pad is provided on a surface of the multi-layer wiring part. One end of the thermal via connects to the die pad, while the other end of the thermal via passes through the multi-layer wiring part and extends at least to the ceramic substrate. The thermal via is electrically insulated from the multi-layer wiring part. In the second multi-layer wiring substrate, at least one of end portions of the above thermal via is wider than a section of the other portion of the thermal via, resulting in further improvement of the heat dissipating property.
Inventors
- 👤 Takeshi Miyagi
- 👤 Kazuhiro Matsumoto
- 👤 Tomiya Sasaki
- 👤 Hideo Iwasaki
- 👤 Katsumi Hisano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:01
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/611; H10W40/00; H10W40/20; H10W40/22; H10W40/226; H10W40/228; H10W70/67; H10W70/68; H10W70/685; H05; H05K; H05K1/00; H05K1/02; H05K1/0201; H05K1/0296; H05K1/0298; H05K1/14; H05K1/144; H10W90/00; H10W90/701; H10W90/751; H10W90/754
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
269 words
A multi-layer wiring substrate comprising: a ceramic substrate; a wiring layer comprising a wiring formed in an electrical insulating material, the wiring layer being integrally formed on the ceramic substrate; a die pad for mounting thereon an electronic part, the die pad being provided on a surface of the wiring layer; and a thermal via of a column shape for transferring heat, the thermal via being provided in the wiring layer so as to pass through at least the wiring layer in a direction of a wiring layer thickness and contact the ceramic substrate and the die pad; wherein a sectional area of an end portion of the thermal via is larger than an average sectional area, and satisfy the following equation: ##EQU4## wherein d: when a square, which has the same area as the sectional area of the smallest portions of the thermal via, is assumed, d is the length of one side of the square; d e : when a square, which has the same area as the sectional area of the end portion of the thermal via contacting the die pad or substrate, is assumed, d e is the length of one side of the square; d av : when a square, which has the same area as the average area of the sectional portions of the thermal via, is assumed, d av is the length of one side of the square; D: the average pitch of the thermal via contacting the die pad; L: the length of the thermal via; and h: the length of the portion of the thermal via having d e .
Claim 2
Dependent Claim
269 words
A multi-layer wiring substrate comprising: a ceramic substrate; a wiring layer comprising a wiring formed in an electrical insulating material, the wiring layer being integrally formed on the ceramic substrate; a die pad for mounting thereon an electronic part, the die pad being provided on a surface of the wiring layer; and a thermal via of a column shape for transferring heat, the thermal via being provided in the wiring layer so as to pass through at least the wiring layer in a direction of a wiring layer thickness and contact the ceramic substrate and the die pad; wherein a sectional area of an end portion of the thermal via is larger than an average sectional area, and satisfy the following equation: ##EQU4## wherein d: when a square, which has the same area as the sectional area of the smallest portions of the thermal via, is assumed, d is the length of one side of the square; d e : when a square, which has the same area as the sectional area of the end portion of the thermal via contacting the die pad or substrate, is assumed, d e is the length of one side of the square; d av : when a square, which has the same area as the average area of the sectional portions of the thermal via, is assumed, d av is the length of one side of the square; D: the average pitch of the thermal via contacting the die pad; L: the length of the thermal via; and h: the length of the portion of the thermal via having d e .
Claim 3
Dependent Claim
16 words
The multi-layer wiring substrate of claim 1, wherein the ceramic substrate is an aluminum nitride substrate.
Claim 4
Dependent Claim
15 words
The multi-layer wiring substrate of claim 1, wherein the electric insulative material is polyimide resin.
Claim 5
Dependent Claim
38 words
The multi-layer wiring substrate of claim 1, wherein the multi-layer wiring substrate further comprises a heat radiating fin being provided on a surface of the ceramic substrate opposite to the surface on which the wiring layer is formed
Claim 6
Dependent Claim
42 words
The multi-layer wiring substrate of claim 1, wherein all the area of a part where the thermal via contacts the surface of the die pad is preferably ranged from about 5 to 20% of all the area of the die pad surface.
Claim 7
Dependent Claim
20 words
The multi-layer wiring substrate of claim 1, wherein the thermal via is electrically insulated from the thin-film multi-layer wiring part.
Claim 8
Dependent Claim
18 words
The multi-layer substrate of claim 1, wherein a longitudinal section of the thermal via is shaped like "]".
Claim 9
Dependent Claim
21 words
The multi-layer wiring substrate of claim 1, wherein a longitudinal section of the thermal via is shaped like a letter "L".
Claim 10
Dependent Claim
29 words
The multi-layer wiring substrate of claim 1, wherein a longitudinal section of the thermal via is gradually reduced in a direction from the end portion to a center portion.
Claim 11
Dependent Claim
37 words
The multi-layer wiring substrate of claim 9, wherein a sectional area of at least one of end portions of the thermal via is larger than an average sectional area of the other portion of the thermal via.
Claim 12
Dependent Claim
132 words
A multi-layer wiring substrate comprising: a ceramic multi-layer wiring substrate having an electric insulating layer of aluminum nitride; a thin-film multi-layer wiring part having an electric insulating layer of an organic polymer, the thin-film multi-layer wiring part being integrally formed on a first surface of the ceramic multi-layer wiring substrate; a die pad for mounting thereon an electronic part, the die pad being provided on a surface of the thin-film multi-layer wiring part; and at least one thermal via, one end of the thermal via being connected to the die pad, the other end of the thermal via passing through the thin-film multi-layer wiring part and extending to at least the first surface of the ceramic multi-layer wiring substrate; wherein the thermal via is electrically insulated from the thin-film multi-layer wiring part.
Claim 13
Dependent Claim
132 words
A multi-layer wiring substrate comprising: a ceramic multi-layer wiring substrate having an electric insulating layer of aluminum nitride; a thin-film multi-layer wiring part having an electric insulating layer of an organic polymer, the thin-film multi-layer wiring part being integrally formed on a first surface of the ceramic multi-layer wiring substrate; a die pad for mounting thereon an electronic part, the die pad being provided on a surface of the thin-film multi-layer wiring part; and at least one thermal via, one end of the thermal via being connected to the die pad, the other end of the thermal via passing through the thin-film multi-layer wiring part and extending to at least the first surface of the ceramic multi-layer wiring substrate; wherein the thermal via is electrically insulated from the thin-film multi-layer wiring part.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-04-09 | 1999-10-09 | 2000-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-04-09 | 2003-10-09 | 2004-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-04-09 | 2007-10-09 | 2008-04-09 | $7700.00 | Window Closed / Lapsed |