Mitsui Kinzoku (Copper Foil Division) Mitsui Kinzoku is a a Japanese manufacturer and distributor of non-ferrous metals and engineered materials. IDTechEx spoke to Mitsui Kinzoku to learn more about its MicroThin series of copper foils for IC substrates at Semicon Europa 2025. Mitsui Kinzoku (Copper Foil Division)