METHOD OF ELECTROPLATING COPPER INTO A VIA ON A SUBSTRATE FROM AN ACID COPPER ELECTROPLATING BATH

摘要

Copper electroplating baths containing primary alcohol alkoxylate block copolymers and ethylene oxide/propylene oxide random copolymers having specific HLB ranges are suitable for filling vias with copper, where such copper deposits are substantially void-free and substantially free of surface defects.

主权项

1. A method of filling a via in an electronic device with copper comprising:
a) providing an acid copper electroplating bath comprising a source of copper ions, an acid electrolyte, a source of halide ions, an accelerator, a leveler, a primary alcohol alkoxylate block copolymer having a formula:wherein R is a linear or branched (C1-C15) alkyl moiety or a linear or branched (C2-C15) alkenyl moiety and m and n can be the same or different and are moles of each moiety wherein the primary alcohol alkoxylate has a weight average molecular weight of 500 g/mole to 20,000 g/mole and a random or block alkoxylate copolymer comprising ethylene oxide and propylene oxide moieties wherein the random or block alkoxyalte copolymer has an HLB of 16 to 35 and the copper electroplating bath has a surface tension ≦40 mN/m;
b) providing as a cathode an electronic device substrate having one or more vias to be filled with copper and having a conductive surface; c) contacting the electronic device substrate with the copper electroplating bath; and d) applying a potential for a period of time sufficient to fill the vias with a copper deposit; wherein the copper deposit in the vias is substantially void-free and substantially free of surface defects.