US5704116A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of holding a component using an anhydride fluxing agent
Assignee: Motorola Solutions Inc
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Filing: 1996-05-03
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Granted: 1998-01-06
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Expires: 2016-05-03
Abstract
Abstract A solution (20) is dispensed onto bond pads (18) on a substrate (14). An integrated circuit component (12) that includes solder bumps (16) formed on component bond pads (30) is superposed onto the substrate (14) such that the solder bumps (16) rest against the bond pads (18). The solution (20) includes an anhydride compound that acts as a fluxing agent. The subassembly (11) is heated to a temperature sufficient to bond the solder bumps (16) to the bond pads (18) to form solder bump interconnections (26). During the bonding process, the fluxing agent substantially vaporizes and leaves virtually no residue on the substrate (14) to allow the component (12) to be effectively underfilled with a polymeric encapsulant (24).
Inventors
- 👤 Daniel Roman Gamota
- 👤 Steven Lewis Wille
- 👤 Steven Michael Scheifers
- 👤 Michael Hertsberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:04
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3489; B; B23; B23K; B23K35/00; B23K35/22; B23K35/36; B23K35/3612; H10; H10W; H10W72/00; H10W72/30; H10W74/00; H10W74/01; H10W74/012; H10W74/10; H10W74/15; H05K3/341; H05K3/3431; H10W72/071; H10W72/073; H10W72/851; H10W72/853; H10W72/856; H10W90/00; H10W90/701; H10W90/721; H10W90/724; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144; Y10T29/49146
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
90 words
A method for attaching an integrated circuit component comprising a plurality of solder bumps to a substrate comprising a plurality of bond pads, the method comprising: dispensing a solution onto the bond pads, said solution comprising a fluxing agent composed of an anhydride compound; superposing the integrated circuit component onto the substrate such that each of said solder bump rests against one of the bond pads and is held by the fluxing agent; and heating to bond the solder bumps to the bond pads and to vaporize the anhydride compound.
Claim 2
Independent Claim
90 words
A method for attaching an integrated circuit component comprising a plurality of solder bumps to a substrate comprising a plurality of bond pads, the method comprising: dispensing a solution onto the bond pads, said solution comprising a fluxing agent composed of an anhydride compound; superposing the integrated circuit component onto the substrate such that each of said solder bump rests against one of the bond pads and is held by the fluxing agent; and heating to bond the solder bumps to the bond pads and to vaporize the anhydride compound.
Claim 3
Dependent Claim
15 words
A method in accordance with claim 1, wherein the anhydride compound is methylhexahydrophthalic anhydride compound.
Claim 4
Dependent Claim
19 words
A method in accordance with claim 2, wherein the solution comprises methylhexahydrophthalic anhydride compound dissolved in a vaporizable vehicle.
Claim 5
Dependent Claim
15 words
A method in accordance with claim 1, wherein the anhydride compound is methyltetrahydrophthalic anhydride compound.
Claim 6
Dependent Claim
19 words
A method in accordance with claim 4, wherein the solution comprises methyltetrahydrophthalic anhydride compound dissolved in a vaporizable vehicle.
Claim 7
Dependent Claim
21 words
A method in accordance with claim 1, wherein the step of heating reflows a solder layer formed on the bond pads.
Claim 8
Independent Claim
131 words
A method for attaching an integrated circuit component comprising a plurality of solder bumps to a substrate comprising a plurality of bond pads, the method comprising: dispensing a solution comprising a fluxing agent composed of an anhydride compound and dissolved in a vaporizable vehicle onto the substrate including the bond pads; vaporizing the vehicle to form a tacky layer on the bond pads; superposing an integrated circuit component onto the substrate such that each of said solder bump rests against one of the bond pads and is held by the tacky layer, and such that a gap is formed between the integrated circuit component and the substrate; heating to bond the solder bumps to the bond pads and to vaporize the anhydride compound; and filling the gap with a polymeric encapsulant.
Claim 9
Independent Claim
131 words
A method for attaching an integrated circuit component comprising a plurality of solder bumps to a substrate comprising a plurality of bond pads, the method comprising: dispensing a solution comprising a fluxing agent composed of an anhydride compound and dissolved in a vaporizable vehicle onto the substrate including the bond pads; vaporizing the vehicle to form a tacky layer on the bond pads; superposing an integrated circuit component onto the substrate such that each of said solder bump rests against one of the bond pads and is held by the tacky layer, and such that a gap is formed between the integrated circuit component and the substrate; heating to bond the solder bumps to the bond pads and to vaporize the anhydride compound; and filling the gap with a polymeric encapsulant.
Claim 10
Dependent Claim
18 words
A method in accordance with claim 7, wherein the solution consists essentially of methylhexahydrophthalic anhydride in vaporizable alcohol.
Claim 11
Dependent Claim
20 words
A method in accordance with claim 7, further comprising the step of removing the anhydride compound vapors from the gap.
Claim 12
Dependent Claim
35 words
A method in accordance with claim 7, wherein the polymeric encapsulant is formed of a resinous composition that cures at a curing temperature, wherein the polymeric encapsulant reacts with residual anhydride at the curing temperature.
Claim 13
Dependent Claim
21 words
A method in accordance with claim 7, wherein the step of heating reflows a solder layer formed on the bond pads.
Claim 14
Independent Claim
159 words
A method for attaching an integrated circuit component comprising a plurality of solder bumps to a substrate comprising a plurality of bond pads, the method comprising: dispensing a solution composed of an anhydride compound dissolved in vaporizable alcohol onto the substrate such that the solution is applied to the bond pads; vaporizing the alcohol to form a tacky anhydride layer on the bond pads; superposing the integrated circuit component onto the substrate such that each of said solder bumps rests against one of the bond pads and is held by the tacky anhydride layer, and such that a gap is formed between the integrated circuit component and the substrate; heating to bond the solder bumps to the bond pads and to vaporize the tacky anhydride layer; and filling the gap with an epoxy-base resinous encapsulant that cures at a curing temperature and includes epoxy end groups and hydroxyl end groups that react with residual anhydride at the curing temperature.
Claim 15
Independent Claim
159 words
A method for attaching an integrated circuit component comprising a plurality of solder bumps to a substrate comprising a plurality of bond pads, the method comprising: dispensing a solution composed of an anhydride compound dissolved in vaporizable alcohol onto the substrate such that the solution is applied to the bond pads; vaporizing the alcohol to form a tacky anhydride layer on the bond pads; superposing the integrated circuit component onto the substrate such that each of said solder bumps rests against one of the bond pads and is held by the tacky anhydride layer, and such that a gap is formed between the integrated circuit component and the substrate; heating to bond the solder bumps to the bond pads and to vaporize the tacky anhydride layer; and filling the gap with an epoxy-base resinous encapsulant that cures at a curing temperature and includes epoxy end groups and hydroxyl end groups that react with residual anhydride at the curing temperature.
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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) | 2001-01-05 | 2001-07-07 | 2002-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-05 | 2005-07-07 | 2006-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-05 | 2009-07-07 | 2010-01-06 | $7700.00 | Window Closed / Lapsed |