Internal-antenna-driven inductive RF discharges for development of large-area high-density plasma sources with suppressed electrostatic coupling

摘要

Large-area high-density RF plasmas at 13.56 MHz have been produced by inductive coupling of an internal-type double half-loop antenna (320 mm diameter), which was immersed in the discharge chamber with 400 mm inner diameter and 200 mm height The plasma source could be operated stably at RF input power of up to 2.5 kW to attain plasma densities as high as 5×10{sup}11 cm{sup}(-3) at argon pressures around 1 Pa, simultaneously achieving effectively suppressed electrostatic coupling. Azimuthal distribution of the plasma density showed the nonuniformity with m = 2 mode, which was found to be controlled by the RF voltage distribution along the antenna and the gas pressure.