Simulation of plasma ion implantation into inner surfaces of rectangular tube

The effects of the electrode geometries, including the circular, triangular, and rectangular configurations, on the dose distribution in plasma ion implantation into the inner surfaces of a rectangular tube were modeled, simplified, and simulated, to improve the uniformity of the dose distribution. In the simulation, software package Matlab was used based on particle-in-cell model. The simulated results show that the circular and triangular electrodes produced the "M-shaped", double-peak distribution of the incident ions. When the electrode is similar to the rectangular tube, the difference between the ion dose distributions on the long and short sides was found to increase. The small-sized rectangular electrode and the rectangular electrode with its short sides enclosed with the two side-matching hemi-circular ends result in three peaks and two valleys of the dose distributions. The statistics of the dose density show that the small-sized rectangular electrode produces higher dose uniformity; the rectangular electrode with hemi-circular ends generates higher local uniformity.