US5300340A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically conductive pressure-sensitive adhesive tape
Assignee: 3M Co
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Filing: 1992-04-22
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Granted: 1994-04-05
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Expires: 2012-04-22
Abstract
Abstract Electrically conductive elements on two substrates can be electrically interconnected by an adhesive tape containing electrically conductive equiax particles that are individually positioned in the adhesive layer in a predetermined pattern. Each particle is harder than the elements it is to interconnect, so that hand pressure causes the particles to penetrate into the elements, thus creating a reliable electrical connection. Particularly useful particles are glass beads having a metallic coating that is from 0.1 to 2 μm thick.
Inventors
- 👤 Clyde D. Calhoun
- 👤 Maurice J. Fleming
- 👤 George D. Foss
- 👤 Richard L. Renstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:06
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/20; H01B1/22; C; C09; C09J; C09J7/00; C09J7/20; C09J9/00; C09J9/02; H01R; H01R4/00; H01R4/04; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/321; H05K3/323; H05K3/36; H05K3/368; H05K2201/00; H05K2201/02; H05K2201/0203; H05K2201/0206; H05K2201/0221; H05K2201/023; H05K2201/09; H05K2201/09818; H05K2201/09945; H05K2201/10; H05K2201/10227; H05K2201/10234; H05K2203/00; H05K2203/02; H05K2203/0278; H05K2203/03; H05K2203/0338; H05K3/361; Y; Y10; Y10S; Y10S428/00; Y10S428/906; Y10T; Y10T428/00; Y10T428/14; Y10T428/1424; Y10T428/1429; Y10T428/24; Y10T428/24355; Y10T428/24372; Y10T428/2438; Y10T428/24413; Y10T428/24479; Y10T428/24521; Y10T428/24545; Y10T428/24802; Y10T428/24843; Y10T428/24893; Y10T428/25; Y10T428/256; Y10T428/28; Y10T428/2852; Y10T428/2857
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
135 words
Adhesive tape comprising a backing carrying an adhesive layer of substantially uniform thickness in which are individually positioned in a predetermined pattern of laterally spaced, electrically conductive, equiax particles of substantially uniform diameter about equal to or somewhat larger than the adhesive thickness, thus making the adhesive layer electrically conductive through its thickness and electrically insulating laterally, wherein the improvement comprises: said particles having a hardness relative to the hardness of an electrically conductive element to which the tape is to be bonded so that when two of said elements are adhered together with a piece of the tape, the particles penetrate those elements upon application of pressure, form a crater in said elements and remove oxides, and substantially all of said particles have a diameter about equal to or larger than the adhesive thickness.
Claim 2
Dependent Claim
135 words
Adhesive tape comprising a backing carrying an adhesive layer of substantially uniform thickness in which are individually positioned in a predetermined pattern of laterally spaced, electrically conductive, equiax particles of substantially uniform diameter about equal to or somewhat larger than the adhesive thickness, thus making the adhesive layer electrically conductive through its thickness and electrically insulating laterally, wherein the improvement comprises: said particles having a hardness relative to the hardness of an electrically conductive element to which the tape is to be bonded so that when two of said elements are adhered together with a piece of the tape, the particles penetrate those elements upon application of pressure, form a crater in said elements and remove oxides, and substantially all of said particles have a diameter about equal to or larger than the adhesive thickness.
Claim 3
Dependent Claim
38 words
Adhesive tape as defined in claim 1 wherein said adhesive is a pressure-sensitive adhesive, and both the diameter of the equiax particles and the thickness of the adhesive layer are within the range of 25 to 150 μm.
Claim 4
Dependent Claim
46 words
Adhesive tape as defined in claim 2 wherein each of said equiax particles has a core with a Knoop Hardness Value of at least 300 and an electrically conductive surface layer, the thickness of which is no more than 10% of the diameter of the core.
Claim 5
Dependent Claim
25 words
Adhesive tape as defined in claim 3 wherein the thickness of the electrically conductive surface layer is within the range of 0.1 to 2 μm.
Claim 6
Dependent Claim
37 words
Adhesive tape as defined in claim 4 wherein the core of said equiax particles is selected from ceramic, steel, nickel, and work-hardened copper, and the electrically conductive surface layer is selected from gold, silver, tin, and solder.
Claim 7
Dependent Claim
15 words
Adhesive tape as defined in claim 5 wherein the electrically conductive particles are substantially spherical.
Claim 8
Dependent Claim
43 words
Adhesive tape as defined in claim 1 wherein said adhesive is a pressure-sensitive adhesive, and a great length of the tape is wound upon itself in roll form, said predetermined pattern repeating a large number of times over the length of the tape.
Claim 9
Dependent Claim
35 words
Adhesive tape as defined in claim 1, the adhesive of which is a pressure-sensitive adhesive and the backing of which is a disposable carrier web having a low-adhesion backsize coating covering each of its faces.
Claim 10
Dependent Claim
17 words
Electrically conductive pressure-sensitive adhesive tape as defined in claim 8 wherein the pressure-sensitive adhesive is a silicone.
Claim 11
Dependent Claim
31 words
Electrically conductive pressure-sensitive adhesive tape as defined in claim 9 wherein the backing is biaxially oriented poly(ethyleneterephthalate) film, both surfaces of which have a low-adhesion backsize coating of a perfluoropolyether polymer.
Claim 12
Dependent Claim
25 words
Adhesive tape as defined in claim 1 wherein the electrically conductive particles occupy from 0.05 to 5 percent of the area of the adhesive layer.
Claim 13
Dependent Claim
46 words
Adhesive tape as defined in claim 1 wherein the particles occupy individual, laterally spaced positions, there being only one particle per position except for two or three particles at a few positions, the particles occupying no more than 5% of the area of the adhesive layer.
Claim 14
Dependent Claim
36 words
Adhesive tape as defined in claim 1 wherein the tape is designed to form electrical connections to pads of an integrated circuit chip or the like, a plurality of particles being located at each pad-contacting area.
Claim 15
Dependent Claim
23 words
Adhesive tape as defined in claim 1 wherein said equiax particles occupy from 0.05 to 1.0% of the area of the adhesive layer.
Claim 16
Dependent Claim
29 words
Adhesive tape as defined in claim 2 and wound upon itself in a roll of great length, said equiax particles being arranged in rows extending both longitudinally and laterally.
Claim 17
Dependent Claim
32 words
Adhesive tape as defined in claim 1 wherein said adhesive layer is in contact with and adhered to said electrically conductive elements and wherein said particles have penetrated said electrically conductive elements.
Claim 18
Dependent Claim
36 words
Adhesive tape as defined in claim 1 which has been applied to said electrically conductive elements, pressure has been applied to said elements, and said particles have penetrated said elements as a result of said pressure.
Claim 19
Dependent Claim
18 words
Adhesive tape as defined in claim 1 wherein said particles have a Knoop hardness of at least 300.
Claim 20
Dependent Claim
129 words
Adhesive tape comprising a backing carrying an adhesive layer of substantially uniform thickness in which are individually positioned in a predetermined pattern of laterally spaced, electrically conductive, equiax particles of substantially uniform diameter about equal to or somewhat larger than the adhesive thickness, thus making the adhesive layer electrically conductive throughout its thickness and electrically insulating laterally, wherein: said particles have a Knoop Hardness Value of at least 300 and have a hardness that is greater than that of an electrically conductive element, so that when such elements are adhered together with a piece of the tape, the particles penetrate those elements upon application of pressure and form a crater in said elements and remove oxides; and wherein substantially every particle is exposed at one face of the adhesive.
Claim 21
Dependent Claim
129 words
Adhesive tape comprising a backing carrying an adhesive layer of substantially uniform thickness in which are individually positioned in a predetermined pattern of laterally spaced, electrically conductive, equiax particles of substantially uniform diameter about equal to or somewhat larger than the adhesive thickness, thus making the adhesive layer electrically conductive throughout its thickness and electrically insulating laterally, wherein: said particles have a Knoop Hardness Value of at least 300 and have a hardness that is greater than that of an electrically conductive element, so that when such elements are adhered together with a piece of the tape, the particles penetrate those elements upon application of pressure and form a crater in said elements and remove oxides; and wherein substantially every particle is exposed at one face of the adhesive.
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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) | 1997-04-04 | 1997-10-04 | 1998-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-04-04 | 2001-10-04 | 2002-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-04-04 | 2005-10-04 | 2006-04-05 | $7700.00 | Window Closed / Lapsed |