Patent US4970570A successfully refreshed from Google Patents.
US4970570A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Use of tapered head pin design to improve the stress distribution in the braze joint
Assignee: International Business Machines Corp
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Filing: 1989-10-16
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Granted: 1990-11-13
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Expires: 2009-10-16
Abstract
Abstract The present invention teaches a structure for reducing the stresses created on a substrate and on the bonding surface at which a connector is attached. The connector has a tapered or beveled head thereby tapering the stress away from the edges of the bonding surface and therefore away from the high stress areas of the substrate, preventing cracking and delamination problems that might otherwise result. The tapered-head geometry also allows greater flexibility in manufacturing the connectors particularly when fabricating pins using a cold-heading process in that a quarter shank diameter:pin head diameter ratio can be obtained.
Inventors
- 👤 Birendra N. Agarwala
- 👤 Paul H. Palmateer
- 👤 Da-Yuan Shih
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:41
CPC Classifications
H; H10; H10W; H10W90/00; H10W90/701; H10W70/00; H10W70/099; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K3/3421; H05K3/3426
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
87 words
An interconnection system for a substrate comprising; at least one electrically conductive pin brazed to said substrate, said pin having a head and a shank, said shank having a first diameter, said head having a bonding surface with a second diameter, said second diameter is uniformly increasing than said first diameter, and an acute angle is made between said bonding surface and said first diameter, and wherein the stress across said bonding surface is minimized by at least reducing said braze volume at said pin head periphery.
Claim 2
Dependent Claim
87 words
An interconnection system for a substrate comprising; at least one electrically conductive pin brazed to said substrate, said pin having a head and a shank, said shank having a first diameter, said head having a bonding surface with a second diameter, said second diameter is uniformly increasing than said first diameter, and an acute angle is made between said bonding surface and said first diameter, and wherein the stress across said bonding surface is minimized by at least reducing said braze volume at said pin head periphery.
Claim 3
Dependent Claim
87 words
A connector to be brazed to a substrate for electrically connecting that substrate to another electrical entity comprising; a bonding surface having a first diameter; a shank for interconnection, having a second diameter which is less than said first diameter; and a tapered portion extending from the shank to the bonding surface at an acute angle to said bonding surface, and wherein the stress across said bonding surface is minimized by at least reducing said braze volume at the periphery of said first diameter of said connector.
Claim 4
Dependent Claim
87 words
A connector to be brazed to a substrate for electrically connecting that substrate to another electrical entity comprising; a bonding surface having a first diameter; a shank for interconnection, having a second diameter which is less than said first diameter; and a tapered portion extending from the shank to the bonding surface at an acute angle to said bonding surface, and wherein the stress across said bonding surface is minimized by at least reducing said braze volume at the periphery of said first diameter of said connector.
Claim 5
Dependent Claim
27 words
The connector of claim 2, wherein the tapered portion is beveled wherein the angle defined by said beveled portion to the bonding surface is less than 90°.
Claim 6
Dependent Claim
16 words
The connector of claim 2, wherein the tapered portion is beveled at an angle of 45°.
Claim 7
Dependent Claim
11 words
The connector of claim 2, wherein the tapered portion is concave.
Claim 8
Dependent Claim
11 words
The connector of claim 2, wherein the tapered portion is convex.
Claim 9
Dependent Claim
25 words
The connector of claim 2, wherein the ratio of the diameter of the bonding surface to the diameter of the shank is greater than 2.4:1.
Claim 10
Dependent Claim
97 words
A connector assembly brazed to a substrate for electrically connecting said substrate to another electrical entity comprising: at least one bonding pad disposed on the surface of said substrate; at least one connector comprising a flat bonding surface having a first diameter; a shank portion having a second diameter which is less than said first diameter; and a section connecting said shank to said bonding surface, said section having edges which taper from said bonding surface to said shank; and braze material between said bonding pad and said flat bonding surface and extending along said tapered edges.
Claim 11
Dependent Claim
97 words
A connector assembly brazed to a substrate for electrically connecting said substrate to another electrical entity comprising: at least one bonding pad disposed on the surface of said substrate; at least one connector comprising a flat bonding surface having a first diameter; a shank portion having a second diameter which is less than said first diameter; and a section connecting said shank to said bonding surface, said section having edges which taper from said bonding surface to said shank; and braze material between said bonding pad and said flat bonding surface and extending along said tapered edges.
Claim 12
Dependent Claim
30 words
A connector as in claim 8, wherein said tapered edges are beveled wherein the angle between the bonding surface of said connector and the beveled edges is less than 90°.
Claim 13
Dependent Claim
29 words
A connector as in claim 8, wherein the tapered edges are beveled such that the angle between the bonding surface of said connector and the beveled edges is 45°.
Claim 14
Dependent Claim
12 words
A connector as in claim 8, wherein the tapered edges are concave.
Claim 15
Dependent Claim
12 words
A connector as in claim 8, wherein the tapered edges are convex.
Claim 16
Dependent Claim
26 words
A connector as in claim 8, wherein the ratio of the diameter of the bonding surface to the diameter of the shank is greater than 2.4:1.
Claim 17
Dependent Claim
79 words
An electrical component for attachment to an assembly member comprising: a head brazed on a predetermined surface region of said assembly member, said head having tapered edges so as to reduce the stresses applied on said assembly member; and a shank extending from said head; wherein said edges are tapered from said surface to said shank, and wherein the stress across the bonding surface is minimized by at least reducing said braze volume at the periphery of said head.
Claim 18
Dependent Claim
79 words
An electrical component for attachment to an assembly member comprising: a head brazed on a predetermined surface region of said assembly member, said head having tapered edges so as to reduce the stresses applied on said assembly member; and a shank extending from said head; wherein said edges are tapered from said surface to said shank, and wherein the stress across the bonding surface is minimized by at least reducing said braze volume at the periphery of said head.
Claim 19
Dependent Claim
19 words
A component as claimed in claim 14, wherein the surface region and the tapered edges is less than 90°.
Claim 20
Dependent Claim
33 words
A component as claimed in claim 14, wherein the tapered edges are linear and the angle formed by the surface region at which the head is attached and the beveled edges is 45°.
Claim 21
Dependent Claim
20 words
The component of claim 14, wherein the diameter of the shank is substantially smaller than the diameter of the head.
Claim 22
Dependent Claim
24 words
The component of claim 14, wherein the ratio of the diameter of the head to the diameter of the shank is greater than 2.4:1.
Claim 23
Dependent Claim
69 words
In a semiconductor integrated circuit packaging assembly having at least one interconnect pin having shank and pin head brazed on metallic pad located on a dielectric substrate, the improvement comprising; tapered edges on said pin head extending at acute angles from said pad to said shank and adapted to reduce the stresses applied on said adjoining substrate and wherein said braze material is additionally disposed on said tapered edges.
Claim 24
Dependent Claim
69 words
In a semiconductor integrated circuit packaging assembly having at least one interconnect pin having shank and pin head brazed on metallic pad located on a dielectric substrate, the improvement comprising; tapered edges on said pin head extending at acute angles from said pad to said shank and adapted to reduce the stresses applied on said adjoining substrate and wherein said braze material is additionally disposed on said tapered edges.
Claim 25
Dependent Claim
78 words
In a semiconductor integrated circuit packaging assembly having at least one interconnect pin having a pin head brazed to metallic bonding pad located on a dielectric substrate, the improvement comprising; the use of pin having head with beveled edges extending at acute angles from said bonding pad adapted to reduce the total volume of braze in the bond wherein said braze is deposited not only between said head and said bonding pad but also along said beveled edges.
Claim 26
Dependent Claim
78 words
In a semiconductor integrated circuit packaging assembly having at least one interconnect pin having a pin head brazed to metallic bonding pad located on a dielectric substrate, the improvement comprising; the use of pin having head with beveled edges extending at acute angles from said bonding pad adapted to reduce the total volume of braze in the bond wherein said braze is deposited not only between said head and said bonding pad but also along said beveled edges.
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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) | 1993-11-12 | 1994-05-14 | 1994-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-12 | 1998-05-14 | 1998-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-12 | 2002-05-14 | 2002-11-13 | $7700.00 | Window Closed / Lapsed |