Cynic
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Posts: 3
Registered: 18-1-2011
Location: UK
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Doping electrolytic copper
I came across the following quote on another website which I thought was interesting
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Extremely pure copper (greater than 99.95%), called electrolytic copper, can be made by electrolysis. The high purity is needed because most copper is
used to make electrical equipment, and small amounts of impurity metals in copper can seriously reduce its ability to conduct electricity. Even 0.05%
of arsenic impurity in copper, for example, will reduce its conductivity by 15%. Electric wires must therefore be made of very pure copper, especially
if the electricity is to be carried for many miles through high-voltage transmission lines. |
Does anybody know if it would be possible to introduce impurities (dopants?) into existing thin electrolytic copper in order to deliberately increase
the resistance. For example, if you had blank traces on a printed circuit board can anybody suggest a suitable chemical and technique to get
impurities (it doesn't have to be arsenic) into the thin copper layer. The layer is approx 1.5 thousandths of an inch or 35 microns thick on a PCB.
The reason I ask is I am working on a project which would use areas of a PCB as a warming/heating element and it would be useful to introduce a higher
resistance in the copper.
I'd appreciate hearing your ideas and comments.
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bquirky
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Registered: 22-10-2008
Location: Perth Western Australia
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I think the simplest way to increase the resistance of a PCB track would be just to make the track thinner.
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