Research on Uniformity of an Atmospheric He/O₂ Microplasma Jet Array and its Film Processing

The non-uniformity in the downstream area of the atmospheric plasma jet array is an urgent prob-lem to be solved. In this paper,we propose a linear He/O₂ microplasma jet array based on four micropipettes withan exit diameter of 10 μm. The effects of applied voltage on the uniformity of plasma characteristics and modifica-tion effects of polymer films were investigated,and the possible causes of the non-uniformity were discussed. Re-sults show that the jet array has the advantages of low temperature and high reactivity,and the surface modificationeffect of the polymer film is obvious. The luminous intensity,gas temperature,the concentration of O atoms and theO/C ratio all increased with higher applied voltage. But the applied voltage with too low or too large amplitude willaffect the spatial uniformity of the jet array,and this phenomenon might result from the non-uniformity of spatialelectric field distribution and Coulomb force among the multi-jets. The uniformity of the modification area can beimproved by adjusting the applied voltage.