Copper foils for printed circuit board applications and procedures and electrolyte bath solutions for electrodepositing the same

摘要

Copper conductive foil for use in preparing printed circuit boards is electrodeposited from an electrolyte solution containing copper ions, sulphate ions and thiourea. The thiourea operates to decrease the roughness of the foil, to enable operation at higher current densities, and/or to modify the tensile strength and ductility characteristics of the foil. An IPC Class 2 foil is prepared without annealing.