Nakano H., Fukushima H., Kobayashi S., Oue S., Tomioka K., Tsuyama Y., Nakano H., Fukushima H., Kobayashi S., Oue S., Tomioka K., and Tsuyama Y.
Cu electrodeposition experiments were carried out at a current density of 260 A/m2 for 48 h in an electrorefining solution at 60 degrees C, and the effects of the presence of glue, thiourea and chloride ions on the morphology and texture of the deposited Cu were investigated. Chloride ions promoted Cu deposit growth in the (110) direction, while the presence of glue and thiourea resulted in the field-oriented crystal texture type being maintained. In a solution containing the optimum amounts of glue, thiourea and chloride ions a smooth deposit was obtained without any projecting edges associated with anomalous deposition. An increase in the concentrations of glue and chloride ions resulted in local anomalous deposition. The surface became smooth with an increase in the thiourea concentration. For an additive-free solution or solutions containing one or two additives the deposited Cu initially exhibited unoriented dispersed or field oriented type crystal texture, followed by epitaxial growth with increasing deposition time. This was attributed to a decrease in the actual current density due to an increase in the surface roughness of the deposited Cu with deposition time. The continuous epitaxial growth increased the grain size of the deposited Cu resulting in an increase in its asperity., Cu electrodeposition experiments were carried out at a current density of 260 A/m2 for 48 h in an electrorefining solution at 60 degrees C, and the effects of the presence of glue, thiourea and chloride ions on the morphology and texture of the deposited Cu were investigated. Chloride ions promoted Cu deposit growth in the (110) direction, while the presence of glue and thiourea resulted in the field-oriented crystal texture type being maintained. In a solution containing the optimum amounts of glue, thiourea and chloride ions a smooth deposit was obtained without any projecting edges associated with anomalous deposition. An increase in the concentrations of glue and chloride ions resulted in local anomalous deposition. The surface became smooth with an increase in the thiourea concentration. For an additive-free solution or solutions containing one or two additives the deposited Cu initially exhibited unoriented dispersed or field oriented type crystal texture, followed by epitaxial growth with increasing deposition time. This was attributed to a decrease in the actual current density due to an increase in the surface roughness of the deposited Cu with deposition time. The continuous epitaxial growth increased the grain size of the deposited Cu resulting in an increase in its asperity.