Patent attributes
A source gas is supplied into a chamber through a nozzle, and electromagnetic waves are thrown from a plasma antenna into the chamber. The resulting Cl2 gas plasma causes an etching reaction to a plurality of copper protrusions, which are arranged between a substrate and a ceiling member in a discontinuous state relative to the flowing direction of electricity in the plasma antenna, to form a precursor (CuxCly). The precursor (CuxCly) transported toward the substrate controlled to a lower temperature than the temperature of an etched member is converted into only Cu ions by a reduction reaction, and directed at the substrate to form a thin Cu film on the surface of the substrate. The speed of film formation is fast, the cost is markedly decreased, and the resulting thin Cu film is of high quality.