US5135155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermocompression bonding in integrated circuit packaging
Assignee: International Business Machines Corp
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Filing: 1991-03-04
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Granted: 1992-08-04
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Expires: 2011-03-04
Abstract
Abstract A contact member for thermocompression bonding in integrated circuit packaging has on a conductor end a uniform texture deformable layer with a hardness value in the range of that of soft gold which is approximately 90 on the Knoop scale and with a rough surface morphology having ridges with approximately 1 micrometer modulation frequency and a depth between ridges of from 1/4 to 1/2 that of the average integrated circuit pad. The deformable layer is produced by plating gold in a strong electronegative plating bath within a range of 0.03 to 0.05 mA/sq.mm. current density. Plating apparatus, for plating different areas, with different electronegative conditions, with separate independently powered anodes, is provided.
Inventors
- 👤 Sung K. Kang
- 👤 Michael J. Palmer
- 👤 Timothy C. Reiley
- 👤 Robert D. Topa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:34
CPC Classifications
H; H10; H10W; H10W99/00; B; B23; B23K; B23K20/00; B23K20/02; B23K20/023; B23K20/22; B23K20/233; B23K33/00
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
85 words
A method comprising: providing a substrate with a contact pad thereon; providing a conducting member having an end, the surface of at least a portion of said end having ridges with a spacing of from about 1/4 to about over half the combined thickness of said pad and said end after bonding, the height of said ridges being from about 1/4 to 1/2 the thickness of said pad; and applying thermocompression bonding force and temperature to the combination of said pad and said conducting member.
Claim 2
Independent Claim
85 words
A method comprising: providing a substrate with a contact pad thereon; providing a conducting member having an end, the surface of at least a portion of said end having ridges with a spacing of from about 1/4 to about over half the combined thickness of said pad and said end after bonding, the height of said ridges being from about 1/4 to 1/2 the thickness of said pad; and applying thermocompression bonding force and temperature to the combination of said pad and said conducting member.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein said ridges are in a surface layer of a material having a hardness of less than about 90 on the Knoop scale.
Claim 4
Dependent Claim
28 words
The method of claim 1 wherein said ridges are in a surface layer of a material taken from the group of Au, Pd, Pt, Ag, Ir and Ni.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein said thermocompression bonding temperature is in a range up to about 500° C.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein said conducting member is a beam lead and said substrate is an electronic device.
Claim 7
Dependent Claim
29 words
The method of claim 5 wherein said beam lead end has a surface layer from about 0.3 to 1.3 micrometers thick and said pad is about 1 micrometer thick.
Claim 8
Independent Claim
58 words
A method comprising: providing a substrate with a pad thereon; providing a conducting member having an end, a part of said end having ridges in a surface layer of a material having a hardness on the Knoop scale of less than 90, and thermocompression bonding said end to said pad at a temperature less than about 500° C.
Claim 9
Independent Claim
58 words
A method comprising: providing a substrate with a pad thereon; providing a conducting member having an end, a part of said end having ridges in a surface layer of a material having a hardness on the Knoop scale of less than 90, and thermocompression bonding said end to said pad at a temperature less than about 500° C.
Claim 10
Dependent Claim
36 words
The method of claim 7 wherein the spacing between said ridges is between 1/4 to 1/2 the thickness of said pad and wherein the depth between said ridges is less than the thickness of said pad.
Claim 11
Dependent Claim
24 words
The method of claim 7 wherein said surface layer is a material taken from the group of Au, Pd, Pt, Ag, Ir and Ni.
Claim 12
Dependent Claim
22 words
The method of claim 7 wherein said bonding temperature is in the range of from about 350° C. to about 500° C.
Claim 13
Dependent Claim
20 words
The method of claim 7 wherein said conducting member is a beam lead and said substrate is an electronic device.
Claim 14
Independent Claim
134 words
The method of thermocompression bonding of a conductor end to an integrated circuit pad comprising in combination the steps of: providing an integrated circuit substrate with at least one contact pad thereon, positioning at least one conducting member having a thermocompression bonding end in contact with at least one said pad, each said end having on at least a portion thereof a deformable layer of a uniform consistency material with a hardness of less than 90 on the Knoop scale taken from the group of Au, Pd, Pt, Ag, Ir and Ni, the surface morphology of said deformable layer having ridges that in spacing and depth are of the order of up to the thickness of said pad, and applying thermocompression bonding force and temperature to the combination of said end and said pad.
Claim 15
Independent Claim
134 words
The method of thermocompression bonding of a conductor end to an integrated circuit pad comprising in combination the steps of: providing an integrated circuit substrate with at least one contact pad thereon, positioning at least one conducting member having a thermocompression bonding end in contact with at least one said pad, each said end having on at least a portion thereof a deformable layer of a uniform consistency material with a hardness of less than 90 on the Knoop scale taken from the group of Au, Pd, Pt, Ag, Ir and Ni, the surface morphology of said deformable layer having ridges that in spacing and depth are of the order of up to the thickness of said pad, and applying thermocompression bonding force and temperature to the combination of said end and said pad.
Claim 16
Dependent Claim
21 words
The method of claim 12 wherein said temperature is in the range of from about 350° C. to about 500° C.
Claim 17
Dependent Claim
25 words
The method of claim 12 wherein the spacing of said ridges is about 100 micrometers and the thickness of said pad is about 100 micrometers.
Claim 18
Dependent Claim
90 words
In a process of thermocompression bonding of a first member to a second member wherein said first and second members are positioned in contact with each other and are subjected to a combination of heat and pressure, the improvement comprising: providing on at least one of said members at least at the region of contact of said members a deformable material with ridges on the surface thereof that in depth and spacing are of the order of the thickness of the thermocompression bond region of said first and second members.
Claim 19
Dependent Claim
90 words
In a process of thermocompression bonding of a first member to a second member wherein said first and second members are positioned in contact with each other and are subjected to a combination of heat and pressure, the improvement comprising: providing on at least one of said members at least at the region of contact of said members a deformable material with ridges on the surface thereof that in depth and spacing are of the order of the thickness of the thermocompression bond region of said first and second members.
Claim 20
Dependent Claim
72 words
The improvement of claim 15 wherein said deformable material is a layer of metal taken from the group of Au, Pd, Pt, Ag, Ir, and Ni, with a hardness on the Knoop scale of approximately 90, said ridges being spaced approximately 1/2 the thickness of the combination of said first member and said second member and said depth between said ridges being about 1/4 to 1/2 the thickness of said second member.
References Cited (Backward Citations)
US3819437A
Cited
US3873428A
Cited
US4188438A
Cited
US4096983A
Cited
US4263606A
Cited
US4169751A
Cited
FR2460347A1
Cited
US4572924A
Cited
US4862322A
Cited
US5027995A
Cited
US5028983A
Cited
US5006917A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-04 | 1996-02-03 | 1996-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-04 | 2000-02-03 | 2000-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-04 | 2004-02-03 | 2004-08-04 | $7700.00 | Window Closed / Lapsed |