Rotational plating process design with computational fluid analysis

Abstract

During the semiconductor manufacturing process and equipment development, we designed a face-up type electro-plating process and equipment including technologies of single wafer processing, wafer handling, and cyclic fluid delivery. In this study, with the help of computational fluid dynamics, we presented the flow effect on the wafer from the viewpoint of the coating uniformity. Process and hardware parameters, such as the electrode rotating speed, the gap between the electrode and the wafer, and the electrode shape were considered. The electrode height of 10 mm exhibited the best results, and this may be caused by the shoulder gap location to the outlet duct. A rotating speed of 5 rpm was shown to produce better results than those at other speeds. The butterfly wing and the meshed disk electrode showed a similar tendency in terms of the rotating speed and the gap. However, the butterfly-wing-type might show less uniform results than those of the meshed disk due to its original non-uniformity in the circumferential direction in case of lower rotating speed.