Method for processing a semiconductor substrate having a copper surface disposed thereon and structure formed
US6362089B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 1999 |
| Grant date | Mar 26, 2002 |
| Priority date | — |
| Expiry date | Apr 19, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12944
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor wafer having copper bondpads (17) that are free of voids (13) and a method for coating the copper bondpads (17) with solderable or wirebondable metals such that the copper bondpads (17) are free of the voids (13). The void free metal coatings are achieved using a dual activation process. In a first activation step (27), the copper bondpads (17) are activated by placing them in a palladium bath. In a second activation step (28), the bondpads are placed in a nickel-boron bath. After the dual activation, the copper bondpads (17) are coated with a layer of nickel-phosphorous or palladium. The nickel-phosphorous or palladium layer may be coated with a layer of gold for subsequent formation of solder balls or wirebonds thereon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.