US3645855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrasonic repair plating of microscopic interconnections
Assignee: International Business Machines Corp
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Filing: 1970-08-14
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Granted: 1972-02-29
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Expires: 1990-08-14
Abstract
Abstract Plating equipment for special applications includes a point tipped ultrasonically agitated bonding tool adapted for electroplating. In the application process the tool receives continuous plating current and intermittent side-to-side ultrasonic agitation. In conjunction with commercial dry film photoresist masks and brush plating solutions the equipment is used to construct microscopic spot plating deposits. The equipment and method are especially useful for customized repair/rework or interconnection elements (vias) in printed circuit devices as a supplement to the basic mass manufacture process. Spot deposits made by this method are formed rapidly, well-adhered and comparable in overall quality to deposits produced on a mass manufacturing scale by conventional immersion plating techniques. Plating current and tool tip diameter critically affect plating quality.
Inventors
- 👤 Renee L Wisman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:08
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/225; C; C25; C25D; C25D5/00; C25D5/20; C25D5/67; H05K3/24; H05K3/241; H05K2203/00; H05K2203/02; H05K2203/0285; H05K2203/17; H05K2203/173
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
141 words
In an electroplating process for producing a microscopic-area plating deposit upon a conductive surface of an electronic part, said surface covered by a mask outlining the microscopic-sized area of said surface which is to receive said deposit, the steps of: placing a drop of dalic plating solution on said part surface in said outlined area; contacting the surface of said drop with the tip of an ultrasonic welding tool; said tip having diameter of at most 0.002 inches; and concurrently applying pulses of ultrasonic vibrations to said element and circulating a DC current of at most 200 microamperes through the series circuit of said element, said drop and said part surface; said vibrations and current being controlled to cause a deposit to form rapidly on said part surface, said deposit characterized by uniform quality and tight adhesion to said part surface.
Claim 2
Dependent Claim
44 words
In a method according to claim 2 the additional steps of: intermittently displacing said element and visually observing growth of said deposit in said outlined area through suitable optical magnification; and terminating operation of said element when said observed deposit reaches a predetermined height.
Claim 3
Dependent Claim
201 words
In an electroplating process for producing multiple microscopic spot deposits of conductive material on a resist-masked conductive surface of an electronic part the procedure for repairing defectively formed deposits prior to stripping the resist mask comprising the steps of: covering correctly formed deposits outlined by said resist mask with a stopoff lacquer; cleaning the masked part thoroughly; adapting the masked part to permit it to receive connection of electrical potential and to conduct said potential to the said masked conductive surface; placing a drop of dalic plating solution over a defective plating site on said part surface outlined by said mask and, intermittently; placing the top of an ultrasonic welding element-tip diameter at most 0.002 inch-in contact with the surface of said drop while coincidentally applying ultrasonic vibrations to said element and circulating a regulated DC electric plating current of at most 200 microamperes through the series electrical circuit formed by said element, said drop and said part surface; and visually observing growth of plating at said site through optical magnification and terminating the plating operation of said element when the plating growth formed by the operation of said element is observed to be level with the surface of the mask.
References Cited (Backward Citations)
US2980594A
Cited
US2978388A
Cited
US2980829A
Cited
US3056938A
Cited
US3324015A
Cited
US3351539A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |