Influence of the power on the particles generated in a low pressure radio frequency nitrogen-rich methane discharge

Particles are generated in low pressure radio frequency (13.56 MHz) CH(4)/N(2) discharges containing 90% of nitrogen. The influence of the radio frequency power supply on the particle presence within the plasma is studied. Particles are evidenced by laser light scattering. The particle formation leads to modifications in the discharge electrical parameters such as the dc self-bias voltage and the phase angle third harmonic. The plasma is analyzed by optical emission spectroscopy by following the temporal evolution of excited species such as CN, N(2), N(2)(+), Ar, and He. Finally, the particle morphology and size are analyzed by scanning electron microscopy. The correlation between these results allows a better understanding of the power influence on the particle growth within the plasma. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3072664]