REMOVAL OF PLASMA DEPOSITED SURFACE LAYERS BY DILUTION GAS SPUTTERING

摘要

A method for limiting the formation of a deposited surface layer on a workpiece, such as a semiconductor wafer, during plasma implantation includes introducing a dopant gas and a dilution gas into a plasma doping chamber for ionization to form dopant gas ions and dilution gas ions, and accelerating the dopant gas ions and the dilution gas ions toward the workpiece. The dopant gas ions are implanted into the workpiece, and the dilution gas ions remove a deposited surface layer from the workpiece. The atomic masses of the dopant gas and the dilution gas may be similar to achieve efficient removal of the deposited surface layer.