Process for removal of metals and alloys from a substrate

A metal that can be dissolved in aqua regia or a metal alloy containing a metal that can be dissolved in aqua regia can be effectively removed from a substrate, and particularly a silicon wafer substrate by a method of application of a composition having a HCl (concentrated)/hydrogen peroxide (concentrated) volume ratio of about 1:1 to about 4:1 that is substantially free of added water. In another embodiment, a metal that can be dissolved in aqua regia or a metal alloy containing a metal that can be dissolved in aqua regia is removed from a substrate by a composition comprising HCl (concentrated)/hydrogen peroxide (concentrated)/water in a volume ratio of from about 2:0.5:4 to about 4:2:4. The composition, heated to a temperature of about 60° C. to about 100° C., is applied to a substrate having the metal or metal alloy thereon, which is preferably heated to a temperature of from about 50° C. to about 100° C. The metal or metal alloy preferably is platinum metal or a metal alloy comprising platinum metal, and the substrate is a silicon wafer substrate.