Hello, I have a question for electrodeposition of gold. So I tried to electroplate gold on a Si wafer with gold seed layer on it. I used SU-8 as my photoresist to form a pattern. But my electroplated gold was black and granular. Area is 19mm^2 and desired thickness is 50 um. I set the effective current to be 1.9 mA. Any ideas? Thank you so much!!!!!