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Polishing Au to the NM scale

2003

Hi,

I'm a graduate student at the University of Arizona. My problem is following: how to polish gold surfaces with good precision ? I would achieve roughness within 1-3 nm range. In other words, I'd like to go below roughness offered by vapor deposition. Or maybe this is the way - my surfaces areas are about 1.5 cm2. If possible I would also prefer to avoid dangerous chemicals like KCN for quite obvious reasons. As of today the best I can get is to mechanically polish surface with 50 nm alumina, but the roughness is still too high. Additionally, I need to get rid of trapped alumina, so I think if I could combine some electrochemical and/or chemical methods this could let me do two things at the time. I would appreciate any references that you could give me on this subject as well as the general subject of metals finishing.

Thank you very much in advance for time, attention and any help that you can offer me.

Macech
University of Arizona - Tucson, Arizona, US

You can mix 100 g/L Thiourea [on eBay or Amazon], water, some wetting agent and a little methane sulfonic acid (about 0.5%). Run parts anodically between 3-5 volts. There are several patents with similar formulations. Check out the Delphi patent search.

Therese Souza
mfg test probes - Attleboro, Massachusetts
2003

Hello Macech! I am a student from Moscow and in this moment I have the similar problem. I want to obtain roughness of surface of gold below 10 nm. Do you have a progress in this question? If yes then could you tell me please about your experience.

Timofey Gorlov
MEPhI, Plasma Physics Department - Moscow
2007