Aqueous copper plating baths and a method for deposition of copper or copper alloy onto a substrate

An aqueous copper plating bath for electrolytic copper or copper alloy deposition comprising

• at least one source of copper ions;
• at least one acid;
• and
• at least one bisurea derivative comprising a bisurea building block according to formula (I)
• wherein A represents a unit derived from a diurea compound of the following formula (A1)
• wherein
• X1 and X2 are divalent residues independently from each other selected from the following group consisting of
• wherein R1 and R2 are monovalent residues each selected independently from the group consisting of hydrogen, alkyl and polyoxyalkylene;
• Y is selected from CH2, 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
• —(CH2)d—[CH(R3)—CH2—O]e—(CH2)f—(CH(CH3))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 R3 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
• —CH2—CH(OH)—CH2—,
• —CH2—CH(SH)—CH2—,—(CH2)g—[CH(R4)—CH2—O]h—(CH2)i— and
• —CH2—CH(OH)—(CH2)j—[CH(R5)—CH2—O]k—(CH2)l—CH(OH)—CH2—
• 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 R4 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;
• l is an integer ranging from 1 to 4;
• each R5 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 added zinc ions.