Simulation of pulse width impact on cavity mold(I) surface modified by plasma ion implantation

The impact of the plasma pulse width on various parameters of interest, including the potential distribution in the plasma sheath, ion motions and dosage, sputtering energy and incident angle, in the surface modification by plasma ion implantation of cavity mold of metal dies was numerically simulated with the two-dimensional particle-in-cell/Monte Carlo collision model. The simulated results show that the pulse width significantly affects the quality of ion implantation. As the width increases, the implantation dosage becomes decreasingly less uniform with increasing number of high energy ions. However, the width little affects the incident angle of the impinging ions. The pulse width can be optimized by compromising the ion energy and dosage, because large pulse width spoils uniformity of the ion beam, and decreases energies of the impinging ions.