The present invention relates to aqueous acidic plating baths for copper and copper alloy deposition in the manufacture of printed circuit boards, IC substrates, semiconducting and glass devices for electronic applications. The plating bath according to the present invention comprises copper ions, at least one acid and an ureylene polymer comprising amino residues on both termini and which is free of organically bound halogen. The plating bath is particularly useful for filling recessed structures with copper and build-up of pillar bump structures.
