Investigation of the Growth of Carbon Films by Ar/CH₄ Plasma Jet Driven by 100-MHz/100-kHz Dual Frequency Source at Atmospheric Pressure

The effects of radio-frequency (RF) power on the formation and growth of carbon films are investigated in Ar/CH4 plasma jet driven by the 100-MHz/100-kHz dual-frequency at atmospheric pressure. The excited species, morphology, and structure of the samples were evaluated by optical emission spectroscopy (OES), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR), respectively. These results showed that as the RF power increases, the size of the carbon particles becomes smaller, and the deposition area becomes larger. The morphology became more plain and smooth with the increase in the RF power. The 1-D particle-in-cell/Monte Carlo (PIC/MC) method was used to calculate the electron and ion densities and electric field. With the increase in the RF power, both the electron density and the sheath depth increases, resulting in a mode transition.