Patent ID: 8747643

Claim:
A copper electroplating bath comprising: a source of copper ions, an acid electrolyte, an accelerator, and a leveling agent, wherein the accelerator comprises one or more sulfur atoms and has a molecular weight of 1000 or less, and wherein the leveling agent is a reaction product of one or more cyclodiaza-compounds with one or more epoxide-containing compounds; wherein at least one cyclodiaza-compound has the formula (I) wherein E=C(O) or CR 3 R 4 ; G=CR 5 R 6 or a chemical bond; R 1 and R 2 are independently chosen from H, (C 1 -C 6 )alkyl and (C 6 -C 10 )aryl; R 3 to R 10 are independently chosen from H, (C 1 -C 6 )alkyl, (C 6 -C 10 )aryl and hydroxyl; each of R 1 and R 2 , R 2 and R 3 , R 3 and R 5 , R 5 and R 7 , R 7 and R 9 , and R 9 and R 1 may be taken together to form a chemical bond; and any of R 1 to R 10 on adjacent ring atoms may be taken together along with the atoms to which they are attached to form a 5- or 6-membered saturated or unsaturated ring; wherein the electroplating bath is acidic.