Mechanisms and behavioral regularities of the vacuum-arc microparticles near and on a potential electrode immersed in plasma

It is experimentally revealed that the pulse-periodic bias potential provides a multifold decrease in the surface content of microparticles (MPs). It is ascertained that a decrease in the MP concentration at the target can be explained by several physical mechanisms. From experiments with a fine-structure grid, it is found that less than 10% of MPs negatively charged in the plasma can be reflected in the electric field of the charge-separation layer near the sample. A substantial decrease in the MP density occurs after direct interaction between a MP and the sample under the action of a negative HF short-pulse bias potential. Almost half the MP surface density is caused by ion sputtering. A twelvefold reduction in the MP surface density is attained when the target is irradiated for 2 min.