20090184092 | Palladium-Selective Etching Solution and Method for Controlling Etching Selectivity - Disclosed is an iodine-based etching solution for etching a material wherein palladium and gold coexist. This etching solution contains at least one additive selected from the group consisting of nitrogen-containing five-membered ring compounds, alcohol compounds, amide compounds, ketone compounds, thiocyanic acid compounds, amine compounds and imide compounds. The etching rate ratio between palladium and gold (etching rate of palladium/etching rate of gold) is not less than 1. | 07-23-2009 |