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Carbon nanotubes ͑CNTs͒ were grown on Si substrates by rf CH 4 plasma-enhanced chemical vapor deposition in a pressure range of 1 -10 Torr, and then characterized by scanning electron microscopy. At 1 Torr, the CNTs continued growing up to 60 min, while their height at 4 Torr had leveled off at 20 min. CNTs hardly grew at 10 Torr and amorphous carbon was deposited instead. CH 4 plasma was simulated using a one-dimensional fluid model to evaluate the production and transport of radicals, ions, and nonradical neutrals. The amount of simulated carbon supplied to the electrode surface via the flux of radicals and ions such as CH 3 , C 2 H 5 , and C 2 H 5 + was consistent with estimations from experimental results.

A self-consistent one-dimensional modelling of a Xe gas discharge between electrodes covered with dielectric barrier is presented for power frequencies from 50 kHz to 1 MHz and gas pressures from 10 to 400 Torr. Spatiotemporal profiles of the concentration of electrons, ions, excited atoms and excimers are obtained. Excimers are mainly produced in the sheath regions. The efficiencies of spontaneous emission from excimers and resonance-state atoms increase with an increase in the input powers for gas pressures higher than 50 Torr. A characteristic period during which the barrier wall charge significantly influences the electric field in bulk region was found, and discharge properties in the period are discussed.

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Xe dielectric barrier discharges at different gap lengths under applied pulse voltages with trapezoidal and sinusoidal waveforms were simulated using a self-consistent one-dimensional fluid model. In both waveforms, the light output power depended not only on the amplitude of voltage waveforms but also on the discharge gap length. At the narrower discharge gap, the light output efficiency was improved by increasing the time gradient of the applied voltage when the trapezoidal pulse is applied, and by decreasing the duty ratio in the sinusoidal case. In the present simulation, we adopted a fast numerical method for calculation of electric field introducing an exact expression of the discharge current.