US6121676A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stacked microelectronic assembly and method therefor
Assignee: Adeia Semiconductor Solutions LLC
•
Filing: 1997-12-11
•
Granted: 2000-09-19
•
Expires: 2017-12-11
Abstract
Abstract A method of making a stacked microelectronic assembly such as a semiconductor chip assembly and its resulting structure includes providing a flexible substrate having a plurality of attachment sites and conductive terminals and including a wiring layer with leads extending to the attachment sites. The method includes assembling a plurality of microelectronic elements to the attachment sites and electrically interconnecting the microelectronic elements and the leads so that the electrically connected microelectronic elements are movable relative to the flexible substrate. The flexible substrate is then folded so as to stack at least some of the microelectronic elements in substantially vertical alignment with one another to provide a stacked assembly with the conductive terminals exposed at the bottom end of the stack. The stacked assembly is held in place using a thermally conductive adhesive and/or a mechanical element. The stacking structure and methods of the present invention provide an economical and space-saving assembly for use in electronic components. The flexibility of the electrical connection between each microelectronic element and the substrate provides for reliable electrical interconnections between the substrate and the microelectronic elements during thermal cycling.
Inventors
- 👤 Vernon Solberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:14
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/18; H05K1/189; H10; H10W; H10W70/00; H10W70/60; H10W70/611; H10W70/67; H10W70/688; H10W90/00; H10W72/00; H10W72/071; H10W72/072; H10W72/07251; H10W72/20; H10W72/60; H10W72/90; H10W90/20; H10W90/291; H10W90/297; H10W90/701; H10W90/721; H10W90/724; H10W90/731; H10W90/732
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
148 words
A method of making a stacked microelectronic assembly comprising: a) providing a flexible substrate having a plurality of attachment sites, said flexible substrate including conductive terminals accessible at a surface thereof and wiring connected to said terminals and including flexible leads extending to said attachment sites; b) providing compliant elements atop said attachment sites; c) assembling a plurality of microelectronic elements to said attachment sites, wherein said compliant elements are disposed between said microelectronic elements and said attachment sites; d) electrically connecting said microelectronic elements and said flexible leads, wherein said electrically connected microelectronic elements are movable relative to said flexible substrate; e) folding said flexible substrate and stacking at least some of said microelectronic elements in substantially vertical alignment with one another; f) maintaining said stacked microelectronic elements in said substantially vertical alignment, wherein said conductive terminals are exposed at a bottom end of said stacked assembly.
Claim 2
Independent Claim
148 words
A method of making a stacked microelectronic assembly comprising: a) providing a flexible substrate having a plurality of attachment sites, said flexible substrate including conductive terminals accessible at a surface thereof and wiring connected to said terminals and including flexible leads extending to said attachment sites; b) providing compliant elements atop said attachment sites; c) assembling a plurality of microelectronic elements to said attachment sites, wherein said compliant elements are disposed between said microelectronic elements and said attachment sites; d) electrically connecting said microelectronic elements and said flexible leads, wherein said electrically connected microelectronic elements are movable relative to said flexible substrate; e) folding said flexible substrate and stacking at least some of said microelectronic elements in substantially vertical alignment with one another; f) maintaining said stacked microelectronic elements in said substantially vertical alignment, wherein said conductive terminals are exposed at a bottom end of said stacked assembly.
Claim 3
Dependent Claim
25 words
A method as claimed in claim 1, wherein said flexible substrate includes a polymeric material and has a thickness between approximately 25 to 75 microns.
Claim 4
Dependent Claim
22 words
A method as claimed in claim 1, wherein said wiring layer interconnects at least some of said microelectronic elements with one another.
Claim 5
Dependent Claim
15 words
A method as claimed in claim 1, wherein said microelectronic elements include a memory chip.
Claim 6
Dependent Claim
30 words
A method as claimed in claim 1, further comprising the step of connecting said conductive terminals with an external circuit element for interconnecting said microelectronic elements and said circuit element.
Claim 7
Dependent Claim
43 words
A method as claimed in claim 5, wherein the assembling step includes aligning the contacts on the front face of said microelectronic element with said leads at said attachment site and abutting the front face of said microelectronic element against said attachment site.
Claim 8
Dependent Claim
40 words
A method as claimed in claim 6, further comprising the step of providing a plurality of compliant pads between the front face of said microelectronic element and said attachment site before the assembling step, said compliant pads defining channels therebetween.
Claim 9
Dependent Claim
49 words
A method as claimed in claim 7, further comprising allowing a curable liquid encapsulant to flow between said microelectronic element and said attachment site and through said channels between said compliant pads and curing said encapsulant to provide a compliant interface between said microelectronic element and said attachment site.
Claim 10
Dependent Claim
35 words
A method as claimed in claim 1, wherein the stacking step includes the step of grouping said at least some of said microelectronic elements in pairs and juxtaposing said paired microelectronic elements with one another.
Claim 11
Dependent Claim
50 words
A method as claimed in claim 9, wherein each said microelectronic element includes a front face bearing contacts and a back surface, each said microelectronic element being assembled to the substrate with its front face being toward the attachment site and its back surface facing away from the attachment site.
Claim 12
Dependent Claim
27 words
A method as claimed in claim 10, wherein the juxtaposing step includes the step of abutting said back surfaces of said paired microelectronic elements with one another.
Claim 13
Dependent Claim
31 words
A method as claimed in claim 11, wherein the maintaining step includes the step of applying an adhesive between the back surfaces of said paired microelectronic elements before the abutting step.
Claim 14
Dependent Claim
15 words
A method as claimed in claim 12, wherein said adhesive includes a thermally conductive material.
Claim 15
Dependent Claim
23 words
A method as claimed in claim 12, wherein the maintaining step includes the further step of applying an adhesive to said flexible substrate.
Claim 16
Dependent Claim
15 words
A method as claimed in claim 14, wherein said adhesive includes a thermally conductive material.
Claim 17
Dependent Claim
27 words
A method as claimed in claim 14, wherein the maintaining step includes the further step of providing a mechanical element in contact with said stacked microelectronic elements.
Claim 18
Dependent Claim
23 words
A method as claimed in claim 16, wherein said mechanical element includes a bracket abutting against the top of said stacked microelectronic elements.
Claim 19
Dependent Claim
28 words
A method as claimed in claim 11, wherein the maintaining step includes the step of providing a mechanical element holding with said stacked microelectronic elements in vertical alignment.
Claim 20
Dependent Claim
23 words
A method as claimed in claim 18, wherein said mechanical element includes a bracket abutting against the top of said stacked microelectronic elements.
Claim 21
Dependent Claim
16 words
A method as claimed in claim 19, wherein said mechanical element includes a thermally conductive material.
Claim 22
Dependent Claim
25 words
A method as claimed in claim 20, further comprising the step of providing thermally conductive sheets between the back surfaces of said paired microelectronic elements.
Claim 23
Dependent Claim
27 words
A method as claimed in claim 21, said thermally conductive sheets being in heat transfer communication with said mechanical element for transferring heat from said microelectronic elements.
Claim 24
Dependent Claim
140 words
A stacked microelectronic assembly comprising: a flexible substrate having a plurality of attachment sites, said flexible substrate including conductive terminals accessible at a surface thereof and wiring connected to said terminals and including flexible leads extending to said attachment sites; a plurality of microelectronic elements assembled to said attachment sites and electrically connected to said leads, compliant elements disposed between said microelectronic elements and said attachment sites wherein said electrically connected microelectronic elements are movable relative to said flexible substrate after said compliant elements have been disposed therebetween; said flexible substrate being folded so that at least some of said microelectronic elements are stacked in substantially vertical alignment with one another; and a securing element maintaining said stacked microelectronic elements in substantially vertical alignment with one another, wherein said conductive terminals are exposed at a bottom end of said assembly.
Claim 25
Dependent Claim
140 words
A stacked microelectronic assembly comprising: a flexible substrate having a plurality of attachment sites, said flexible substrate including conductive terminals accessible at a surface thereof and wiring connected to said terminals and including flexible leads extending to said attachment sites; a plurality of microelectronic elements assembled to said attachment sites and electrically connected to said leads, compliant elements disposed between said microelectronic elements and said attachment sites wherein said electrically connected microelectronic elements are movable relative to said flexible substrate after said compliant elements have been disposed therebetween; said flexible substrate being folded so that at least some of said microelectronic elements are stacked in substantially vertical alignment with one another; and a securing element maintaining said stacked microelectronic elements in substantially vertical alignment with one another, wherein said conductive terminals are exposed at a bottom end of said assembly.
Claim 26
Dependent Claim
25 words
An assembly as claimed in claim 23, wherein said flexible substrate includes a polymeric material and has a thickness between approximately 25 and 75 micros.
Claim 27
Dependent Claim
16 words
An assembly as claimed in claim 23, wherein each said microelectronic element includes a semiconductor chip.
Claim 28
Dependent Claim
22 words
An assembly as claimed in claim 23, wherein said wiring layer interconnects at least some of said microelectronic elements with one another.
Claim 29
Dependent Claim
16 words
An assembly as claimed in claim 23, wherein said flexible substrate includes a substantially S-shaped pattern.
Claim 30
Dependent Claim
16 words
An assembly as claimed in claim 23, wherein said flexible substrate includes a substantially spiral pattern.
Claim 31
Dependent Claim
31 words
An assembly as claimed in claim 23, further comprising a rigid element substantially coextensive with said conductive terminals, said rigid element support said conductive terminals at the bottom of said assembly.
Claim 32
Dependent Claim
21 words
An assembly as claimed in claim 23, wherein said conductive terminals are electrically connected to at least some of said leads.
Claim 33
Dependent Claim
29 words
An assembly as claimed in claim 30, wherein said conductive terminals are electrically interconnected to an external circuit element for interconnecting said microelectronic elements and said external circuit element.
Claim 34
Dependent Claim
26 words
An assembly as claimed in claim 23, further comprising a resilient element between the front face of each said microelectronic element and each said attachment site.
Claim 35
Dependent Claim
20 words
An assembly as claimed in claim 32, wherein said resilient element includes a plurality of compliant pads defining channels therebetween.
Claim 36
Dependent Claim
28 words
An assembly as claimed in claim 23, wherein each said microelectronic element includes a front face bearing contacts and a back surface facing away from said attachment site.
Claim 37
Dependent Claim
33 words
An assembly as claimed in claim 34, wherein at least some of said stacked microelectronic elements are grouped in pairs, the back surfaces of said paired microelectronic elements being juxtaposed with one another.
Claim 38
Dependent Claim
23 words
An assembly as claimed in claim 35, wherein said securing element includes an adhesive between the back surfaces of said paired microelectronic elements.
Claim 39
Dependent Claim
18 words
An assembly as claimed in claim 36, wherein said adhesive is between overlapping sections of said flexible substrate.
Claim 40
Dependent Claim
32 words
An assembly as claimed in claim 35, wherein said securing element includes a mechanical element including a thermally conductive material, said mechanical element abutting against the top of said stacked microelectronic elements.
Claim 41
Dependent Claim
22 words
An assembly as claimed in claim 38, wherein said mechanical element includes cooling fins on a surface thereof for dissipating heat therefrom.
Claim 42
Dependent Claim
14 words
An assembly as claimed in claim 38, wherein said mechanical element comprises a bracket.
Claim 43
Dependent Claim
21 words
An assembly as claimed in claim 38, further comprising thermally conductive sheets between said back surfaces of said paired microelectronic elements.
Claim 44
Dependent Claim
31 words
An assembly as claimed in claim 41 said thermally conductive sheets being in heat transfer communication with said mechanical element for transferring heat from said microelectronic elements to said mechanical element.
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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) | 2003-09-19 | 2004-03-20 | 2004-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-09-19 | 2008-03-20 | 2008-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-09-19 | 2012-03-20 | 2012-09-19 | $7700.00 | Window Closed / Lapsed |