US5747101A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct chip attachment (DCA) with electrically conductive adhesives
Assignee: GlobalFoundries Inc
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Filing: 1996-04-09
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Granted: 1998-05-05
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Expires: 2016-04-09
Abstract
Abstract A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.
Inventors
- 👤 Richard B. Booth
- 👤 Michael A. Gaynes
- 👤 Robert M. Murcko
- 👤 Viswanadham Puligandla
- 👤 Judith M. Roldan
- 👤 Ravi Saraf
- 👤 Jerzy M. Zalesinski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:13
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/20; H10W72/30; H10W74/00; H10W74/01; H10W74/012; H10W74/10; H10W74/15; H10W72/01; H10W72/013; H10W72/01331; H10W72/071; H10W72/072; H10W72/07251; H10W72/073; H10W72/07331; H10W72/251; H10W72/253; H10W72/851; H10W72/853; H10W72/856; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49204; Y10T29/49208; Y10T29/49222
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
95 words
A method of making integrated circuit chips comprising the steps of: applying an insulative thermoplastic adhesive paste, over a semiconductor wafer substrate having a plurality of chip sites and integrated circuits communicating with a matrix of conductive metal pads on a major surface of the substrate; drying the insulative thermoplastic; forming holes in the insulative thermoplastic layer at the metal pads; filling the holes with a conductive thermoplastic adhesive paste; and drying the conductive thermoplastic to form a dry composite adhesive layer dividing the wafer into a plurality of chips after forming the composite layer.
Claim 2
Independent Claim
95 words
A method of making integrated circuit chips comprising the steps of: applying an insulative thermoplastic adhesive paste, over a semiconductor wafer substrate having a plurality of chip sites and integrated circuits communicating with a matrix of conductive metal pads on a major surface of the substrate; drying the insulative thermoplastic; forming holes in the insulative thermoplastic layer at the metal pads; filling the holes with a conductive thermoplastic adhesive paste; and drying the conductive thermoplastic to form a dry composite adhesive layer dividing the wafer into a plurality of chips after forming the composite layer.
Claim 3
Dependent Claim
44 words
The method recited in claim 1 wherein the step of applying an insulative adhesive is performed by spin coating the substrate surface with a adhesive paste and drying, and the step of forming holes in the insulative thermoplastic layer is performed by laser ablation.
Claim 4
Dependent Claim
30 words
The method recited in claim 1 wherein the insulative adhesive layer is dried and pre-formed with punched holes and then bonded directly to the chip surface with heat and pressure.
Claim 5
Dependent Claim
38 words
The method recited in claim 1 wherein the insulative adhesive layer is applied by emulsion screening to place the adhesive everywhere except chip bond pads, thereby simultaneously performing the steps of applying the adhesive and forming the holes.
Claim 6
Dependent Claim
39 words
The method recited in claim 1 wherein the substrate is an integrated circuit wafer having a plurality of chip sites, and further including the step of dividing the wafer into a plurality of chips after drying both thermoplastic adhesives.
Claim 7
Dependent Claim
21 words
The method recited in claim 1 wherein the drying steps include heating to a temperature of at least about 80° C.
Claim 8
Dependent Claim
32 words
The method recited in claim 1 further including the step of heating the substrate to a temperature between about 150° C. and about 300° C. to bond the adhesives to the substrate.
Claim 9
Dependent Claim
18 words
The method recited in claim 1 wherein the holes are filled with conductive adhesive paste by mask screening.
Claim 10
Independent Claim
94 words
A method of making integrated circuit chips comprising the steps of: providing a semiconductor wafer substrate having a plurality of chip sites and integrated circuits communicating with a matrix of conductive metal contact pads on a major surface of the substrate; depositing conductive thermoplastic adhesive paste bumps on the metal pads; drying the conductive adhesive; applying an insulative thermoplastic adhesive over the substrate surface between the conductive adhesive deposits; curing the insulative adhesive to form a dry composite adhesive layer; and dividing the wafer into a plurality of chips after forming the composite layer.
Claim 11
Independent Claim
94 words
A method of making integrated circuit chips comprising the steps of: providing a semiconductor wafer substrate having a plurality of chip sites and integrated circuits communicating with a matrix of conductive metal contact pads on a major surface of the substrate; depositing conductive thermoplastic adhesive paste bumps on the metal pads; drying the conductive adhesive; applying an insulative thermoplastic adhesive over the substrate surface between the conductive adhesive deposits; curing the insulative adhesive to form a dry composite adhesive layer; and dividing the wafer into a plurality of chips after forming the composite layer.
Claim 12
Dependent Claim
22 words
The method recited in claim 9 wherein the step of applying the insulative adhesive is performed by emulsion screening of adhesive paste.
Claim 13
Dependent Claim
37 words
The method recited in claim 9 wherein the step of applying the insulative adhesive is performed by forming the insulative adhesive into a film, dried, punched and bonded directly to the chip surface by heat and pressure.
Claim 14
Dependent Claim
27 words
The method recited in claim 9 wherein the step of applying the insulative adhesive is performed by flowing adhesive paste over spaces between the conductive thermoplastic bumps.
Claim 15
Dependent Claim
29 words
The method recited in claim 9 further comprising the step of plating the conductive adhesive bumps with a layer of conductive metal prior to applying an insulative adhesive paste.
Claim 16
Independent Claim
81 words
A method of preparing substrates for attachment comprising the steps of: providing a first semiconductor wafer substrate having a plurality of chip sites with a matrix of conductive metal pads on a major surface; depositing an electrically conductive thermoplastic adhesive paste on the metal pads; depositing an electrically insulating thermoplastic adhesive on the substrate surface around the metal pads; drying the paste; and dividing the semiconductor wafer into a plurality of individual chips after said depositing steps and said drying step.
Claim 17
Independent Claim
81 words
A method of preparing substrates for attachment comprising the steps of: providing a first semiconductor wafer substrate having a plurality of chip sites with a matrix of conductive metal pads on a major surface; depositing an electrically conductive thermoplastic adhesive paste on the metal pads; depositing an electrically insulating thermoplastic adhesive on the substrate surface around the metal pads; drying the paste; and dividing the semiconductor wafer into a plurality of individual chips after said depositing steps and said drying step.
Claim 18
Dependent Claim
41 words
The method recited in claim 14 wherein the electrically insulating adhesive is deposited on the substrate as a paste followed by the additional step of drying the insulating adhesive prior to the step of depositing the conductive adhesive on the pads.
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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) | 2001-05-04 | 2001-11-03 | 2002-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-04 | 2005-11-03 | 2006-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-04 | 2009-11-03 | 2010-05-05 | $7700.00 | Window Closed / Lapsed |