Rotationally asymmetric variable electrode correction
US7682498B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2005 |
| Grant date | Mar 23, 2010 |
| Priority date | — |
| Expiry date | Jan 20, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D21/12
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A work piece is electroplated or electroplanarized using an azimuthally asymmetric electrode. The azimuthally asymmetric electrode is rotated with respect to the work piece (i.e., either or both of the work piece and the electrode may be rotating). The azimuthal asymmetry provides a time-of-exposure correction to the current distribution reaching the work piece. In some embodiments, the total current is distributed among a plurality of electrodes in a reaction cell in order to tailor the current distribution in the electrolyte over time. Focusing elements may be used to create “virtual electrode” in proximity to the surface of the work piece to further control the current distribution in the electrolyte during plating or planarization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.