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Electroplating cobalt onto chromium seed layers

2007

Hi,

I need to electroplate cobalt on a chromium seed layer but the problem is that the coatings exhibit bad adhesion. The bath is a simple cobalt chloride bath at pH=4.

Thank you

Salvador Pané
PhD Student (University of Barcelona) - Switzerland + Spain

You mention chromium seeds. Then what is the rest of the surface made of? Plastic, ceramics, metal? In other words, what type of adhesion mechanism are you attempting?

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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2007

Use cobalt sulphate for your bath. Plated from chloride is too highly stressed internally.
Air agitation from a fish tank compressor will speed up your plating quite a bit also. Do not use the air rock as the acid will destroy it. Heat the end of the tube and pinch it shut with a pair of pliers. "Drill" holes in the plastic tubing with a red hot paper clip (with forceps or pliers) and weight the tube down with stainless steel weld rod or some thing similar.

James Watts
- Navarre, Florida

It is a silicon wafer with evaporated chromium.

Salvador Pané
- Barcelona, Spain
2007