Advances in plasma process technology have contributed directly to advances in the miniaturization and integration of semiconductor devices. However, in semiconductor devices that encroach on the nanoscale domain, defects or damage can be caused by charged particles and ultraviolet rays emitted from the plasma, severely impairing the characteristics of nano-devices that have a larger surface than bulk areas. It is therefore essential to develop a method for suppressing or controlling charge accumulation and ultraviolet damage in plasma processing. The neutral beam process developed by the authors is a method that suppresses the formation of defects at the atomic layer level in the processed surface, allowing ideal surface chemical reactions to take place at room temperature. This technique is indispensable to develop future innovative nano-devices.