Surface Pretreatments for Remove of Native Cu Oxide Layer

In order to remove native Cu oxides formed on Cu seed layer, TS-40A and H2SO4 solutions were used. After various pretreatments, the changed surface of Cu seed layer was estimated by SEM and XPS. For all pretreatments, the mass of samples was decreased. The mass loss of sample treated in H2SO4 solution for 60 s was the largest. After TS-40A pretreatment, native Cu oxide layer is not at all removed although the carbon on Cu seed layer was removed mainly with a few loss of sample mass. By H2SO4 treatment after TS-40A pretreatment, most of native Cu oxides on Cu seed layer were removed with a lot of mass loss and the oxides will be eliminated by control of dipping time. Consequently, we found that the pretreatment by H2SO4 is suitable to obtain a Cu seed layer removed native oxide for electrodeposition.