Adjustable plating cell for uniform bump plating of semiconductor wafers
US5391285A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1994 |
| Grant date | Feb 21, 1995 |
| Priority date | — |
| Expiry date | Feb 25, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/01079
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An apparatus plates metal bumps of uniform height on one surface of a semiconductor wafer (32). A plating tank (12) contains the plating solution. The plating solution is filtered (16) and pumped (14) through an inlet (22) to an anode plate (24) within plating cell (20). The anode plate has a solid center area to block direct in-line passage of the plating solution, and concentric rings of openings closer to its perimeter to pass the plating solution. The distance between the inlet and the anode plate is adjustable with supports to create a uniform flow of the plating solution to the surface of the semiconductor wafer for uniform plating of the array of metal bumps (30). The plating cell contains an adjustable sidewall extension (26) to set the proper distance between the anode plate and the semiconductor wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.