Abstract: A plasma-assisted deposition system for carrying out a plasma-assisted deposition method has a processing vessel defining a vacuum chamber and having an open upper end, a dielectric member covering the open upper end of the processing vessel, and a flat antenna member placed on the upper surface of the dielectric member. A coaxial waveguide has one end connected to the upper surface of the flat antenna member and the other end connected to a microwave generator. The flat antenna member is provided with many slots of a length corresponding to half the wavelength of a microwave arranged on concentric circles. For example, a circularly polarized microwave is radiated from the slots into a processing space to produce a source gas plasma. Electron temperature in the plasma in terms of mean square velocity is 3 eV or below and the electron density in the plasma is 5×1011 electrons per cubic centimeter or above. The plasma is used for depositing a fluorine-containing carbon film.

Abstract: A film forming method comprise the steps of forming a F-doped carbon film by using a source gas containing C and F, and modifying the F-doped carbon film by radicals, the source gas having a F/C ratio, defined as a ratio of a number of F atoms to a number of C atoms in the source gas molecule, wherein the F/C ratio is larger than 1 but smaller than 2.