US5760337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermally reworkable binders for flip-chip devices
Assignee: Shell USA Inc
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Filing: 1996-12-16
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Granted: 1998-06-02
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Expires: 2016-12-16
Abstract
Abstract A semiconductor device is attached to a supporting substrate by a plurality of solder connections that extend from the supporting substrate to the semiconductor device and the gap between the supporting substrate and the semiconductor device is filled with a reworkable composition comprising: (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b). Such a process provides a readily reworkable semiconductor assembly.
Inventors
- 👤 Shridhar R. Iyer
- 👤 Pui Kwan Wong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:04
CPC Classifications
C; C08; C08L; C08L73/00; H; H10; H10W; H10W74/00; H10W74/01; H10W74/012; C08G; C08G67/00; C08G67/02; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/44; H10W72/00; H10W72/30; H10W74/10; H10W74/15; H10W72/851; H10W72/853; H10W72/856; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49146
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
117 words
An encapsulated flip chip assembly comprising: a supporting substrate; at least one semiconductor device attached to said supporting substrate by means of a plurality of solder connections that extend from said supporting substrate to form a gap between said supporting substrate and said semiconductor device; and a thermally reworkable binder filling said gap, said thermally reworkable binder comprising: (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b) thereby providing an assembly.
Claim 2
Dependent Claim
117 words
An encapsulated flip chip assembly comprising: a supporting substrate; at least one semiconductor device attached to said supporting substrate by means of a plurality of solder connections that extend from said supporting substrate to form a gap between said supporting substrate and said semiconductor device; and a thermally reworkable binder filling said gap, said thermally reworkable binder comprising: (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b) thereby providing an assembly.
Claim 3
Dependent Claim
28 words
The flip chip assembly of claim 1 wherein the crosslinked resin is reworkable at a temperature within the range of from about 100° C. to about 250° C.
Claim 4
Dependent Claim
25 words
The flip chip assembly of claim 2 wherein the dienophile is an alkyne having electron withdrawing groups attached to both sides of an ethyne moiety.
Claim 5
Dependent Claim
32 words
The flip chip assembly of claim 3 wherein the dienophile is selected from the group consisting of compounds containing but-2-ene-1,4-dione moieties in 5-membered rings, and compounds containing but-2-ene-1,4-dione moieties in 6-membered rings.
Claim 6
Dependent Claim
43 words
The flip chip assembly of claim 2 wherein the thermally reworkable resin further comprises a residue of a cross-linking agent selected from the group consisting of, bismaleimido-capped poly(alkylene oxide)s, bismaleimido-capped polysiloxanes, bismaleimides of hydrazine, 2,4-diaminotoluene, hexamethylenediamine, dodecamethylenediamine, and diamines of the formula: ##STR6##
Claim 7
Dependent Claim
26 words
The flip chip assembly of claim 1 wherein the 2,5-dialkyl substituted furan-containing polymer is produced by reacting carbon monoxide with at least one olefinically unstaturated compound.
Claim 8
Dependent Claim
16 words
The flip chip assembly of claim 6 wherein the olefinically unsaturated compound is an aliphatic α-olefin.
Claim 9
Dependent Claim
12 words
The flip chip assembly of claim 7 wherein the α-olefin is propene.
Claim 10
Dependent Claim
26 words
The flip chip assembly of claim 2 wherein the polymer from which it is produced has a number average molecular weight in the range of 500-30,000.
Claim 11
Dependent Claim
27 words
The flip chip assembly of claim 4 wherein the 2,5-dialkyl furan-containing polymer has a furan groups to ketone groups ratio of from about 1:16 to about 4:1.
Claim 12
Dependent Claim
35 words
The flip chip assembly of claim 2 wherein the 2,5-dialkyl substituted furan groups in the 2,5-dialkyl substituted furan-containing polymer and the dienophiles are combined in a molar ratio of from about 10:1 to about 1:5.
Claim 13
Dependent Claim
23 words
The flip chip assembly of claim 2 wherein the dienophile is a crosslinking agent containing two or more dienophiles in its molecular structure.
Claim 14
Dependent Claim
36 words
The flip chip assembly of claim 2 wherein the thermally reworkable crosslinked resin is produced by reacting at least one dienophile having a functionality of greater than one and two or more 2,5-dialkyl substituted furan-containing polymer.
Claim 15
Dependent Claim
25 words
The flip chip assembly of claim 2 wherein the thermally reworkable crosslinked resin comprises moieties of a 2,5-dialkyl substituted furan and moieties of a dienophile.
Claim 16
Dependent Claim
18 words
The flip chip assembly of claim 1 further comprising (c) a free radical inhibitor and/or an ion scavenger.
Claim 17
Dependent Claim
123 words
A process of providing an encapsulated flip chip assembly comprising the steps of: attaching at least one semiconductor device to a supporting substrate by a plurality of solder connections that extend from the supporting substrate to said semiconductor device to form a gap between said supporting substrate and said semiconductor device, filling said gap with a thermally reworkable flip chip binder comprising: (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b) thereby providing a flip chip assembly.
Claim 18
Dependent Claim
123 words
A process of providing an encapsulated flip chip assembly comprising the steps of: attaching at least one semiconductor device to a supporting substrate by a plurality of solder connections that extend from the supporting substrate to said semiconductor device to form a gap between said supporting substrate and said semiconductor device, filling said gap with a thermally reworkable flip chip binder comprising: (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b) thereby providing a flip chip assembly.
Claim 19
Dependent Claim
57 words
The process of claim 16 further comprising the steps of: heating the encapsulated flip chip assembly at a temperature which is sufficiently high to melt or soften the solder connections and to convert the thermally reworkable composition into a liquid thereby providing a liquid composition, removing the semiconductor device from the supporting substrate providing a device-removed substrate.
Claim 20
Dependent Claim
163 words
The process of claim 17 further comprising the steps of: cleaning said device-removed supporting substrate free of solder and the thermally reworkable flip chip binder thereby providing a cleaned-supporting substrate, attaching a second semiconductor device to said cleaned-supporting substrate by a plurality of solder connections that extend from the said supporting substrate to said second semiconductor device to form a gap between said supporting substrate and said second semiconductor device, filling said gap with a fresh thermally reworkable flip chip binder comprising: (i) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality of greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (ii) at least one filler present from about 25 to about 75 percent by weight based upon the amount of components and (i) and (ii), and cooling the fresh thermally reworkable composition filled in the gap to a temperature which is sufficiently low to solidify the resin thereby producing a reworked assembly.
Claim 21
Dependent Claim
26 words
The process of claim 17 wherein the crosslinked resin is heated at a temperature within the range of from about 100° C. to about 250° C.
Claim 22
Dependent Claim
27 words
The process of claim 18 wherein the 2,5-dialkyl substituted furan-containing polymer is produced by furanizing a copolymer of carbon monoxide and at least one olefinically unsaturated compound.
Claim 23
Dependent Claim
30 words
The process of claim 16 further comprising heating the assembly at a temperature within the range of 70° C. to 200° C. for a period of up to 4 hours.
Claim 24
Dependent Claim
30 words
The process of claim 16 further comprising heating the assembly at a temperature within the range of 150° C. to 300° C. for a period of up to 4 hours.
Claim 25
Dependent Claim
24 words
The process of claim 16 wherein the 2,5-dialkyl substituted furan-containing polymer is produced by reacting carbon monoxide with at least one olefinically unstaturated compound.
Claim 26
Dependent Claim
14 words
The process of claim 20 wherein the olefinically unsaturated compound is an aliphatic α-olefin.
Claim 27
Dependent Claim
10 words
The process of claim 24 wherein the α-olefin is propene.
Claim 28
Independent Claim
171 words
A method of reworking an encapsulated flip chip assembly comprising the steps of: heating the encapsulated flip chip assembly comprising at least one semiconductor device attached to a supporting substrate by a plurality of solder connections that extend from the supporting substrate to the semiconductor device to form a gap between said supporting substrate and said semiconductor device, and a thermally reworkable flip chip binder filling said gap, said thermally reworkable flip chip binder comprising (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b), at a temperature which is sufficiently high to melt or soften the solder connections and to convert the thermally reworkable composition into a liquid thereby providing a liquid composition, removing the semiconductor device from the supporting substrate providing a device-removed substrate.
Claim 29
Independent Claim
171 words
A method of reworking an encapsulated flip chip assembly comprising the steps of: heating the encapsulated flip chip assembly comprising at least one semiconductor device attached to a supporting substrate by a plurality of solder connections that extend from the supporting substrate to the semiconductor device to form a gap between said supporting substrate and said semiconductor device, and a thermally reworkable flip chip binder filling said gap, said thermally reworkable flip chip binder comprising (a) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (b) at least one filler present in an amount from about 25 to about 75 percent by weight based upon the amount of components (a) and (b), at a temperature which is sufficiently high to melt or soften the solder connections and to convert the thermally reworkable composition into a liquid thereby providing a liquid composition, removing the semiconductor device from the supporting substrate providing a device-removed substrate.
Claim 30
Dependent Claim
163 words
The method of claim 26 further comprising the steps of: cleaning said device-removed supporting substrate free of solder and the thermally reworkable flip chip binder thereby providing a cleaned-supporting substrate, attaching a second semiconductor device to said cleaned-supporting substrate by a plurality of solder connections that extend from the said supporting substrate to said second semiconductor device to form a gap between said supporting substrate and said second semiconductor device, filling said gap with a fresh thermally reworkable flip chip binder comprising: (i) a thermally reworkable crosslinked resin produced by reacting at least one dienophile having a functionality of greater than one and at least one 2,5-dialkyl substituted furan-containing polymer, and (ii) at least one filler present from about 25 to about 75 percent by weight based upon the amount of components and (i) and (ii), and cooling the fresh thermally reworkable composition filled in the gap to a temperature which is sufficiently low to solidify the resin thereby producing a reworked assembly.
Claim 31
Dependent Claim
27 words
The method of claim 27 wherein the 2,5-dialkyl substituted furan-containing polymer is produced by furanizing a copolymer of carbon monoxide and at least one olefinically unsaturated compound.
Claim 32
Dependent Claim
80 words
The flip chip assembly of claim 2 wherein the dienophile is a cyclic derivative of maleic anhydride of the formula: ##STR7## wherein X denotes O, S, N, P, or R wherein R is alkylene and wherein at least one of the free valencies is occupied by a bridging group which connects the dienophile with one of the polymer chains or with another dienophile and wherein the remaining valencies, if an, are occupied by hydrogen, lower alkyl substituents or acyl substituents.
Claim 33
Dependent Claim
23 words
The flip chip assembly of claim 5 wherein the residue of the cross-linking agent is selected from diamines of the general formula ##STR8##
References Cited (Backward Citations)
US3979373A
Cited
US4826932A
Cited
US5120665A
Cited
US5292688A
Cited
US5120678A
Cited
US5274913A
Cited
US5374701A
Cited
US5390082A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-06-01 | 2001-12-01 | 2002-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-01 | 2005-12-01 | 2006-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-01 | 2009-12-01 | 2010-06-02 | $7700.00 | Window Closed / Lapsed |