Development of line-shaped microwave plasma with rectangular slotted waveguide at atmospheric pressure

In this study, line-shaped plasmas are generated with slotted waveguide at 2.45GHz at Atmospheric pressure. The waveguide is designed close to the cut-off condition of TE10 mode and thin dielectric sheets are set in the slot to get a long wavelength in waveguide. Dielectric sheets contribute to decrease ignition threshold of plasma. Permittivity dependence of ignition threshold power for plasma was measured to confirm it. Then an ignition test was performed modifying experimental conditions in terms of getting long line shape plasma based on the measurement results. As the result of the improvement, 23cm of the microwave line shaped plasma using He gas was archived An experiment of plasma exposure to polycarbonate (PC) was performed and it was confirmed that generated plasma is effective for surface modification based on measurement result of water contact angle.