Patent EP0340492A2 successfully refreshed from Google Patents.
EP0340492A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Conformal sealing and interplanar encapsulation of electronic device structures
Assignee: International Business Machines Corp
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Filing: 1989-04-12
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Granted: —
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Expires: 2009-04-12
Abstract
Abstract Electronic device packaging structures wherein the active face (6) of an electronic device (4) is mounted facing a substrate (12). Environmental isolation is provided by an overcoat polymeric material (44) at least sealing the space (41) between the device and substrate at the periphery of the device. Enhanced environmental isolation is provided by a polymeric material disposed to substantially fill the space (41) between the device and substrate. The overcoat polymeric material provides enhanced fatigue life to solder mounds disposed between and electrically interconnecting the device and substrate.
Inventors
- 👤 Joseph George Ameen
- 👤 Stephen Leslie Buchwalter
- 👤 Caroline Ann Kovac
- 👤 Michael Jon Palmer
- 👤 Paige Adams Poore
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 17:50
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/40; H10W74/47; H10W72/00; H10W72/30; H10W74/01; H10W74/012; H10W74/10; H10W74/131; H10W74/15; H10W74/473; H10W72/071; H10W72/073; H10W72/07331; H10W72/851; H10W72/853; H10W72/856; H10W90/00; H10W90/701; H10W90/721; H10W90/724; H10W90/731; H10W90/734
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
127 words
A structure comprising: an electronic device having a back face (14) and an active face (16), there being I/O terminals (8) on at least said active face; a substrate (12) having a surface with contact pads (26) thereon; said substrate and said device being mounted together with said active face of said device facing said substrate surface with contact pads thereon; at least one solder mound (28) electrically joining at least one I/O on said active face of said device to at least one pad on said substrate; a means for improving the fatigue life of said at least one solder mound, said means being an overcoat polymeric material (44) at least sealing the space between said device and said substrate at the periphery of said device.
Claim 2
Dependent Claim
127 words
A structure comprising: an electronic device having a back face (14) and an active face (16), there being I/O terminals (8) on at least said active face; a substrate (12) having a surface with contact pads (26) thereon; said substrate and said device being mounted together with said active face of said device facing said substrate surface with contact pads thereon; at least one solder mound (28) electrically joining at least one I/O on said active face of said device to at least one pad on said substrate; a means for improving the fatigue life of said at least one solder mound, said means being an overcoat polymeric material (44) at least sealing the space between said device and said substrate at the periphery of said device.
Claim 3
Dependent Claim
21 words
The structure of claim 1, wherein said overcoat polymeric material is substantially void-free and formed from a substantially solvent-free liquid polymer.
Claim 4
Dependent Claim
41 words
The structure of claim 1 or claim 2, wherein said overcoat polymeric material conformally coats said back face of said device and at least a part of the surface of said substrate, facing said device, beyond the periphery of said device.
Claim 5
Dependent Claim
67 words
The structure of one of the preceding claims, wherein said overcoat polymeric material adheres to said device and said substrate, has a TCE sufficiently matched to said device and substrate to avoid cracking of said overcoat material from thermal cycling of said structure, and has sufficiently high flexural strength to avoid cracking from any residual TCE mismatch between said substrate, said device and said overcoat polymeric material.
Claim 6
Dependent Claim
30 words
The structure of one of the preceding claims, wherein said polymeric material has thickness greater than about the separation of said device and substrate at the periphery of said device.
Claim 7
Dependent Claim
18 words
The structure of one of the preceding claims 2 to 5, wherein said polymeric material is an epoxy.
Claim 8
Dependent Claim
33 words
The structure of one of the preceding claims 2 to 6, wherein said polymeric material is selected from the group consisting of Hysol FP4322, Hysol CBN 435-21, Hysol FP 4401 and Furane 7704-5.
Claim 9
Dependent Claim
27 words
The structure of one of the preceding claims further including an interplanar polymeric material substantially filling the space (41) between said device (4) and said substrate (12).
Claim 10
Dependent Claim
31 words
The structure of claim 8, wherein said interplanar material is substantially void-free and formed from a substantially solvent-free liquid polymer which flows into the space between said device and said substrate.
Claim 11
Dependent Claim
21 words
The structure of claim 9, wherein said group consisting of a cycloaliphatic epoxide formulation, a silicone and an unfilled flexibilized epoxy.
References Cited (Backward Citations)
No citation records indexed.
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