HMDSO含量对纳秒脉冲激励Ar/HMDSO射流放电特性的影响

Adding Si-containing precursors to the discharge gas can introduce Si-containing groups on the surface of the materials and effectively improve the surface hydrophobicity by plasma treatment, which is important for the improvement of the surface insulating performance of insulators. In this paper, hexamethyldisiloxane (HMDSO) was selected as the Si-containing precursors, and ns pulse excitation was used to generate jet discharges in Ar/HMDSO. The influences of HMDSO ratio on the discharge characteristics were studied by diagnosing the electrical characteristics (voltage and current measurements, etc. ) and optical characteristics (discharge images, emission spectra and ICCD measurements). The variations of plasma plume length, discharge power, transported charge, spectral line intensity of main particles and ionization wave propagation with HMDSO ratio were obtained and further analyzed in combination with the discharge ionization reaction and dynamic development process. The results show that the introduction of a small amount of HMDSO promotes the discharge by the increasing of the length of the jet plume, injection power, transported charge, intensity of the main particle line, ionization wave propagation speed and distance. Those parameters reach the maximum values at 0.04%HMDSO. When the HMDSO content is greater than 0.04%, the discharge is weakened and the corresponding parameters decrease with the increase of the HMDSO ratio. The competition of the direct ionization reaction of HMDSO and the reaction of HMDSO with Ar excited states are the reason for the maximum values of the parameters existing in the studied range of HMDSO addition.