An aqueous copper plating bath for electrolytic copper or copper alloy deposition comprising at least one source of copper ions and at least one acid characterised in that it comprises at least one bisurea derivative comprising a bisurea building block according to formula wherein A represents a unit derived from a diurea compound of the following formula wherein X 1 and X 2 are divalent residues independently from each other selected from the following group consisting of and wherein R 1 and R 2 are monovalent residues each selected independently from the group consisting of hydrogen, alkyl and polyoxyalkylene; Y is selected from CH 2, O and S; c is an integer ranging from 1 to 6; c' is an integer ranging from 1 to 6; b is an integer ranging from 1 to 5; b' is an integer ranging from 1 to 5; Z is a divalent bridging moiety which is selected from the group consisting of alkylene, arylene and alkylene oxide compound whereby said alkylene oxide compound is represented by the following formula -(CH 2) d -[CH(R 3)-CH 2 -O] e -(CH 2) f -(CH(CH 3)) f' -, wherein d is an integer ranging from 0 to 3; e is an integer ranging from 1 to 100; and f is an integer ranging from 1 to 3; f' is 0 or 1; each R 3 is independently from each other selected from the group consisting of alkyl, aryl and hydrogen; a is an integer and ranges from 1 to 100; and D is a divalent residue and is selected from the group consisting of -CH 2 -CH -CH 2 -, -CH 2 -CH -CH 2 -,-(CH 2) g -[CH(R 4)-CH 2 -O] h -(CH 2) i - and -CH 2 -CH -(CH 2) j -[CH(R 5)-CH 2 -O] k -(CH 2) l -CH -CH 2 - wherein g is an integer ranging from 0 to 4; h is an integer ranging from 1 to 100; i is an integer ranging from 1 to 4; each R 4 is independently from each other selected from the group consisting of alkyl, aryl and hydrogen; j is an integer ranging from 1 to 4; k is an integer ranging from 1 to 100; I is an integer ranging from 1 to 4; each R 5 is independently from each other selected from the group consisting of alkyl, aryl and hydrogen and if a is 2 or greater each A and each D are selected independently from each other and wherein the aqueous copper plating bath is free of zinc ions. X 1 and X 2 are divalent residues independently from each other selected from the following group consisting of and wherein R 1 and R 2 are monovalent residues each selected independently from the group consisting of hydrogen, alkyl and polyoxyalkylene; Y is selected from CH 2, O and S; c is an integer ranging from 1 to 6; c' is an integer ranging from 1 to 6; b is an integer ranging from 1 to 5; b' is an integer ranging from 1 to 5; Z is a divalent bridging moiety which is selected from the group consisting of alkylene, arylene and alkylene oxide compound whereby said alkylene oxide compound is represented by the following formula -(CH 2) d -[CH(R 3)-CH 2 -O] e -(CH 2) f -(CH(CH 3)) f' -, wherein d is an integer ranging from 0 to 3; e is an integer ranging from 1 to 100; and f is an integer ranging from 1 to 3; f' is 0 or 1; each R 3 is independently from each other selected from the group consisting of alkyl, aryl and hydrogen; a is an integer and ranges from 1 to 100; and D is a divalent residue and is selected from the group consisting of -CH 2 -CH -CH 2 -, -CH 2 -CH -CH 2 -,-(CH 2) g -[CH(R 4)-CH 2 -O] h -(CH 2) i - and -CH 2 -CH -(CH 2) j -[CH(R 5)-CH 2 -O] k -(CH 2) l -CH -CH 2 - wherein g is an integer ranging from 0 to 4; h is an integer ranging from 1 to 100; i is an integer ranging from 1 to 4; each R 4 is independently from each other selected from the group consisting of alkyl, aryl and hydrogen; j is an integer ranging from 1 to 4; k is an integer ranging from 1 to 100; I is an integer ranging from 1 to 4; each R 5 is independently from each other selected from the group consisting of alkyl, aryl and hydrogen and if a is 2 or greater each A and each D are selected independently from each other and wherein the aqueous copper plating bath is free of zinc ions.