Process for electrolessly plating copper and plating solution therefor
US4935267A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 6, 1988 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | May 6, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C18/40
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
By forming a first copper layer on a substrate by using a complexing agent for copper ion, which has a low copper complex stability constant, a uniform second layer can be stably formed by a second complexing agent for a copper ion, which has a high copper complex stability constant, even if the substrate is composed of a material having a low catalytic activity, such as tungsten, or even if the catalytic activity of the substrate is uneven. A similar effect can also be obtained by adding a small amount of a complexing agent for a copper ion, having a low stability constant, to an electroless copper plating bath containing a complexing agent for a copper ion, having a low stability constant. In this case, an effect of preventing stopping of the reaction of the complexing agent of a copper ion, having a high stability constant, is attained. Most preferably, after formation of a uniform first copper layer by an electroless copper plating solution containing a complexing agent for a copper ion, having a low stability constant, a second copper layer is formed by an electroless copper plating solution containing a complexing agent for a copper ion, having a high stability constant and a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.