What is the best way to make a low resistivity contact to 100-200 nm thick copper traces on SiO2 or Sapphire?

Indium and low temperature solder do not seem to create a resistance lower than 30-40 Ohms when a sputtered copper trace 500um wide x 22mm long x 200nm thick is connected to a copper PCB with Au...

02 February 2015 7,567 2 View