In this project, a systematic electrochemical study will be done to investigate the main reactions involved and determine some of the thermodynamic and kinetic parameters, which will then be used in subsequent modeling of the established mechanism. In addition, copper plating experiments will be done on patterned structures to determine the superfilling kinetics associated with certain solution compositions and the effect of feature size. For the electrochemical techniques, mainly the rotating-ring disk technique will be used. With this technique it is possible to follow the formation of cuprous intermediates during copper electrodeposition and determine the effect of the organic additives.