Today I finally started to characterize the vacuum chamber. Time vs Thickness, A-K voltage vs plasma current and Vacuum.
One thing I found out, is that my newly installed 50/100Ω ballast resistor was not performing well. It just didn’t allow the machine to operate properly (but without characterization, I am not sure where it acted)
With it, all tries ended up like the center piece. Looking like copper oxide, and with 250ohm resistance. Without the resistor, it was easier to achieve and mantain the plasma, and copper sputtered easily. (left and right, copper on glass)
The copper passed the tin-wetting and finger tests (it doesn’t smear when you rub the finger on it).
It’s also so shiny, the camera won’t focus on it, but rahter on the reflected image (ceiling)
That’s a really odd picture!
For fun, I tried to do a simple circuit on glass:
However, the copper film was simply too thin, and the solder paste destroyed it when melting. In any case, that just requires more time in the chamber. I’ll have proper deposition figures soon.