Electroplated copper thin films have been extensively used for interconnections in semiconductor devices. In this paper, electroplating of copper has been investigated to study the dependency of plated film thickness, current efficiency and sheet resistivity on current density. Copper film is electroplated on gold seed layer for via filling using different current densities varying from 10mA/cm2 to 70mA/cm2 at constant temperature (40°C). Annealing analysis for plated thick film is done at 200°C for 30 minutes. Surface roughness reduces along with resistivity with annealing.