One-step, non-contact pattern transfer by direct-current plasma immersion ion implantation

A one-step, non-contact pattern transfer method by direct-current plasma immersion ion implantation is demonstrated. Complex patterns with micrometre-size linewidths can be transferred onto a silicon wafer by placing the metal masks 4 mm away from the wafer. Scanning electron microscopy reveals that by negatively biasing the metal mask, ions coming from a hole with a diameter of 200 µm in the mask can be confined to a smaller region of 100 µm. The ion focusing effect is confirmed by two-dimensional multiple-grid particle-in-cell simulation.