PLATING METHOD

A copper electroplating bath having a surface tension of 40 mN/m is suitable for filling a via with copper, wherein such copper deposit is substantially void-free and free of surface defects. A method for filling a via in an electronic device with copper comprises: providing an acidic copper electroplating bath which includes a source of a copper ion, an acid electrolyte, a halide ion source, an accelerator, a leveler, and a suppressor, and has a dynamic surface tension of 40 mN/m or less; providing an electronic device substrate as a cathode which has one or more vias to be filled with copper, and has a conductive surface; connecting the electronic device substrate to the copper electroplating bath; and applying a potential for a period of time sufficient to fill the via with a copper deposit. 표면 장력이 40 mn/m인 구리 전기도금조는, 구리 침착물에 실질적으로 보이드가 없고 실질적으로 표면 결함 없이, 비아를 구리로 충전하는데 적합하다.