Copper plating method
US9797047B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 2015 |
| Grant date | Oct 24, 2017 |
| Priority date | — |
| Expiry date | May 10, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/17
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of removing copper oxide from copper surfaces is disclosed that comprises application of vapor generated by an ultrasonic wave nebulizer. The energized vapor droplets include water and a weak organic acid such as acetic acid, lactic acid, citric acid, uric acid, oxalic acid, or formic acid that have a vapor pressure proximate to that of water. The weak organic acid preferably has a pKa high enough to avoid Cu etching but is sufficiently acidic to remove copper oxide at a rate that is compatible with high throughput manufacturing. In one embodiment, weak acid/water vapor is applied to a substrate in a spin bowl and is followed by a deionized water rinse step in the same spin bowl. Improved wettability results in improved uniformity in subsequently plated copper films. Considerable cost savings is realized as a result of reduced chemical consumption and higher product yields.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.