A method for fabricating cell plugs of a semiconductor device is disclosed, which increases the operation speed of the semiconductor device by reducing the cell plug resistance of the device. The present invention makes it possible to improve dielectric breakdown strength between interconnects each having a main conductor film comprised mainly of copper. More specifically, the purchase of a plurality of lifetime income shares guarantees an individual a predetermined, periodic income payment for the life of the purchaser. The outer dimensions of the cover plate are selected to cover the face of the electrical box, the screw sockets and the contents of the electrical box. The semiconductor wafer disposed inside the chamber is illuminated with radiation sufficient to create a plurality of electron-hole pairs near the surface of the wafer and to desorb ions and molecules adsorbed on the surface of the wafer.