Simulation and dose uniformity analysis of plasma based ion implantation

Abstract

Plasma based ion implantation for a planar target was simulated using the particle-in-cell model. The plasma sheath evolution and the ion implantation details (the incident ion flux, the ion impact angle and the ion impact energy) were studied for targets with different sizes, with an aim to investigate the dependence of dose uniformity on target size. The effect of plasma density and pulse width on dose distribution was studied as a plus. The simulation results show that a larger target leads to a faster and less cylindrical sheath expansion. By increasing the target size, a more uniform distribution of incident ion flux can be obtained and the normal impact effect can be improved, while the distribution of impact energy is slightly influenced. As a result, the ion implantation dose presents a better uniformity on a larger target. By increasing plasma density or pulse width, we get a higher ion implantation dose but worse dose uniformity.