Metal plugs produced by excimer laser melting for submicron interconnection: mechanism, electrical properties

A new laser planarization technique for producing metal plugs has been developed. In this technique, a thin metal cap which is patterned to cover the entire via hole is used, followed by melting with a XeCl excimer laser irradiation. The molten metal cap is drawn into the via by surface tension forces resulting in the formation of the metal plug. The use of the metal cap means that the plug formation is performed easily and stably. And is an effective method for submicron interconnection. The interconnects were tested on a contact check device composed of 60000 vias connected in series. The characteristics agree well with the results calculated using the electrical resistivity of metal