A. I. Bumagina

Behavior of macroparticles near and on a substrate immersed in a vacuum arc plasma at negative high-frequency short-pulsed biasing

It was found that the negative repetitive pulsed biasing of a substrate with respect to the adjacent plasma significantly reduce the macroparticles (MPs) content on surface. The decrease of MPs on the negative potential substrate surface is caused by several different physical mechanisms. Up to 10% of macroparticles can be repulsed from the plasma-substrate voltage drop after being negatively charged in plasma. The MPs surface density on substrate can be significantly reduced after MPs interaction with negatively biased metal surface. This physical mechanism of negatively charged MPs electrostatic repulsion disappears when tungsten grid is used to create a sheath near the substrate surface. Reduction of MPs surface density almost by half takes a place due to ion sputtering. The decrease of MPs surface density by factor of 12 was achieved after the treatment of substrate for 2 min.

Mechanisms and regularities of the vacuum arc macroparticles behavior near and on a substrate, immersed in plasma

It was found that the negative repetitive pulsed biasing of a substrate with respect to the adjacent plasma significantly reduce the MPs content on surface. The decrease of MPs on the negative potential substrate surface is caused by several different physical mechanisms. Up to 10% of macroparticles (MPs) can be repulsed from the plasma-substrate voltage drop after being negatively charged in plasma. The MPs surface density on substrate can be significantly reduced after MPs interaction with negatively biased metal surface. This physical mechanism of negatively charged MPs electrostatic repulsion disappears when tungsten grid is used to create a sheath near the substrate surface. Reduction of MPs surface density almost by half takes a place due to ion sputtering. The decrease of MPs surface density by factor of 12 was achieved after the treatment of substrate for 2 min.

Influence of Bias Parameters and Plasma Density on Vacuum Arc Macroparticle Accumulation

Several regularities of the accumulation of vacuum arc metal macroparticles (MP) on the sample on repetitively pulsed biasing (105 Hz, 7 µs, −0.5 kV to −3.5 kV) have been investigated. It has been shown that the substrate temperature plays a very important role in controlling the MP amounts on the sample. A possibility to change the metal particle number density on the substrate in the range from 105/cm2 to 107/cm2, depending on bias pulse parameters, sample temperature, and ion plasma saturation current density, has been demonstrated. The shape of MPs and their adhesion to the substrate surface depends strongly on the MP energy balance in a high-voltage space charge sheath.

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.

Application of high-frequency short-pulsed plasma-immersion ion implantation or deposition method for dielectric materials processing using gas, metal and gas-metal plasma

A new approach in the development of advanced coating deposition and ion implantation method including an application of filtered dc metal plasma and high-frequency short-pulsed negative bias voltage with a duty factor in the range 10%-99% are considered. The ion energy spectrum for different negative bias potential pulse duration (120-1100) ns was measured. The map of different methods of ion beam and plasma material treatment using high-frequency short pulse metal plasma immersion ion implantation or deposition depending on bias pulse duty factor and amplitude for Cu plasma is presented. The ion assisted coating deposition depending on samples conductivity and thickness, plasma concentration, pulse repetition rate and amplitude and duty factor has been examined.