Patent US5070875A successfully refreshed from Google Patents.
Patent US6036836A successfully refreshed from Google Patents.
US6036836A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process to create metallic stand-offs on an electronic circuit
Assignee: ST MICROELECTRONICS NV
•
Filing: 1997-12-19
•
Granted: 2000-03-14
•
Expires: 2017-12-19
Abstract
Abstract A process to create metallic stand-offs or studs on a printed circuit board (PCB). The process allows to obtain studs constituted by three successive layers of metal (Cu1, Cu2 and Cu3 or Ni) of which at least the two first layers are made of copper. The height of the so-created stand-off is sufficient to use it in the flip chip technology to assemble chips to a printed circuit board. The present process is implemented according either to the electro-plating (galvano-plating) or to the electrochemical-plating technique.
Inventors
- 👤 Joris Antonia Franciscus Peeters
- 👤 Louis Joseph Vandam
- 👤 Koenraad Juliaan Georges Allaert
- 👤 Ann Marie Ackaert
- 👤 Andre Michel Van Calster
- 👤 Maria Eugenie Andre Vereeken
- 👤 Suixin Zhang
- 👤 Johan De Baets
- 👤 Bart Leo Alfons Maurice Vandevelde
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:48
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/40; H05K3/4007; H05K3/22; H05K3/24; H05K3/243; H10; H10W; H10W70/00; H10W70/099; H10W90/00; H10W90/701; H05K1/00; H05K1/02; H05K1/11; H05K1/111; H05K1/112; H05K1/114; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0347; H05K2201/0364; H05K2201/0367; H05K2203/00; H05K2203/03; H05K2203/0361; H05K2203/07; H05K2203/0703; H05K2203/072; H05K3/0094; H05K3/02; H05K3/06; H05K3/061; H05K3/062; H05K3/10; H05K3/108; H05K3/28; H05K3/42; H05K3/425; H05K3/427
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
204 words
Process to create at least one stand-off on an electronic circuit, characterized in that said stand-off is created on the surface of a printed circuit board constituting said electronic circuit and being coated with a first layer of copper, said process including the sequential steps of: depositing a first layer of photo-resistive material covering said first layer of copper; creating a first pattern uncovering said first layer of copper at least at the location of the future stand-off; plating a second layer of copper onto the uncovered portion of said first layer of copper, said second layer of copper being substantially thicker than said first layer of copper, said second layer of copper forming a second pattern; depositing a second layer of photo-resistive material; creating a third pattern uncovering said second layer of copper at least at the location of said future stand-off; and plating a third layer of copper onto the uncovered portion of said second layer of copper after the step of creating the third pattern, wherein said third layer of copper forms a fourth pattern different from the second pattern and wherein said second layer of copper physically separates said entire third layer of copper from said first layer of copper.
Claim 2
Dependent Claim
204 words
Process to create at least one stand-off on an electronic circuit, characterized in that said stand-off is created on the surface of a printed circuit board constituting said electronic circuit and being coated with a first layer of copper, said process including the sequential steps of: depositing a first layer of photo-resistive material covering said first layer of copper; creating a first pattern uncovering said first layer of copper at least at the location of the future stand-off; plating a second layer of copper onto the uncovered portion of said first layer of copper, said second layer of copper being substantially thicker than said first layer of copper, said second layer of copper forming a second pattern; depositing a second layer of photo-resistive material; creating a third pattern uncovering said second layer of copper at least at the location of said future stand-off; and plating a third layer of copper onto the uncovered portion of said second layer of copper after the step of creating the third pattern, wherein said third layer of copper forms a fourth pattern different from the second pattern and wherein said second layer of copper physically separates said entire third layer of copper from said first layer of copper.
Claim 3
Dependent Claim
79 words
Process according to claim 1, characterized in that, after the step of plating the third layer of copper, said process further includes the sequential steps of: coating said third layer of copper with a protective layer of metal to protect the third layer of copper against etching; stripping said first and second layers of photo-resistive material; etching the unprotected layers of metal until the unprotected first layer of copper is removed; and stripping said protective layer of second metal.
Claim 4
Dependent Claim
26 words
Process according to claim 2, characterized in that it further includes the step of electrochemical plating a layer of nickel onto the unprotected layers of copper.
Claim 5
Dependent Claim
25 words
Process according to claim 3, characterized in that it further includes the step of flash plating a layer of gold onto said layer of nickel.
Claim 6
Dependent Claim
82 words
Process according to claim 1, characterized in that said second layer of copper is also used as a protective layer for said first layer of copper and said process further includes the sequential steps of: coating said third layer of copper with a protective layer of second metal against etching; stripping said first and second layers of photoresist material; etching the unprotected layers of metal until the unprotected first layer of copper is removed, and stripping said protective layer of second metal.
Claim 7
Dependent Claim
222 words
Process to create at least one stand-off on an electronic circuit, characterized in that said stand-off is created on the surface of a printed circuit board constituting said electronic circuit and being coated with a first layer of copper, said process including the sequential steps of: depositing a first layer of photo-resistive material covering said first layer of copper; creating a first pattern uncovering said first layer of copper at least at the location of the future stand-off; plating a second layer of copper onto the uncovered portion of said first layer of copper, said second layer of copper being substantially thicker than said first layer of copper, said second layer of copper forming a second pattern; coating said second layer of copper with a protective layer of second metal against etching; stripping said first layer of photo-resistive material; etching the unprotected first layer of copper; stripping said protective layer of second metal; depositing a layer of photo sensitive dielectric material; creating a third pattern by removing said layer of photo sensitive dielectric material at the location of said future metallic stand-off; and plating a third layer of copper, onto the uncovered portion of said second layer of copper after the step of creating the third pattern, wherein said third layer of copper forms a fourth pattern different from the second pattern.
Claim 8
Dependent Claim
222 words
Process to create at least one stand-off on an electronic circuit, characterized in that said stand-off is created on the surface of a printed circuit board constituting said electronic circuit and being coated with a first layer of copper, said process including the sequential steps of: depositing a first layer of photo-resistive material covering said first layer of copper; creating a first pattern uncovering said first layer of copper at least at the location of the future stand-off; plating a second layer of copper onto the uncovered portion of said first layer of copper, said second layer of copper being substantially thicker than said first layer of copper, said second layer of copper forming a second pattern; coating said second layer of copper with a protective layer of second metal against etching; stripping said first layer of photo-resistive material; etching the unprotected first layer of copper; stripping said protective layer of second metal; depositing a layer of photo sensitive dielectric material; creating a third pattern by removing said layer of photo sensitive dielectric material at the location of said future metallic stand-off; and plating a third layer of copper, onto the uncovered portion of said second layer of copper after the step of creating the third pattern, wherein said third layer of copper forms a fourth pattern different from the second pattern.
Claim 9
Dependent Claim
33 words
Process according to claim 6, characterized in that it further includes the step of electrochemical plating a layer of nickel onto said stand-off using said layer of photo sensitive dielectric material as mark.
Claim 10
Dependent Claim
39 words
Process according to claim 7, characterized in that it further includes the step of flash plating a layer of gold (Au) onto said layer of nickel (Ni) using said layer of photo sensitive dielectric material (MP) as a mask.
Claim 11
Dependent Claim
34 words
Process according to claim 6, characterized in that the second metal of said protective layer is tin-lead, wherein the second metal of said protective layer forms a fifth pattern different from the fourth pattern.
References Cited (Backward Citations)
US4016050A
Cited
EP0354671A1
Cited
US5017509A
Cited
US4946563A
Cited
US5118386A
Cited
US5611140A
Cited
US5283948A
Cited
US5349500A
Cited
US5261593A
Cited
WO1995005675A1
Cited
EP0654818A1
Cited
EP0675532A2
Cited
US5525204A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-03-14 | 2003-09-13 | 2004-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-03-14 | 2007-09-13 | 2008-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-03-14 | 2011-09-13 | 2012-03-14 | $7700.00 | Window Closed / Lapsed |