| abstract |
Several Au layers are consecutively applied to a metal substrate, partic, semi-conductor material, such as Si, starting with a first thin adherent, dense Au intermediate layer, pref. applied after pickling, and pref. deposited from acid electrolyte contg. brightener, followed by electrodeposition of thicker pure Au top layer, pref. >=2 mu m thick, which is deposited from alkaline electrolyte pref. with high CN content, advantageously with Alu:CN (free) ratio =1. Pref. current density in electrolyte is so low that deposition rate is 3-6 mu m/hr. |