D5200 sensor by Toshiba!

mosswings wrote:

Gold is higher conductivity, yes, but more difficult to work with and ceased being used in fine-feature lithography some years ago. Extreme current density applications may still use it, but it also has a bad tendency to kill devices if not properly isolated from the silicon chip itself. In fact, gold was used as a dopant early on to kill carrier lifetimes in high-speed diodes; the penalty was noise and defects. Developing a suitable barrier metal layer that allows the gold to bond properly yet isolates the devices reliably kept most from adopting gold metallization. When Cu interconnect technology was developed, Au for all intents and purposes became obsolete.