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Recent development of large-diameter (>30 cm) high-density (>10 11 cm −3 ) microwave plasma production at low pressures (<20 mTorr) without an external DC magnetic field is reviewed in view of application to the next generation ULSI devices and flat panel displays. Understanding the discharge physics-excitation, propagation and absorption of the surface wave in a flat plasma geometry under overdense conditions (ω p ω)-is indispensable for controlling the plasma. Experimental evidence of discrete surface-wave modes is clearly found in optical emission and microwave field measurements. The analysis of the full-wave electromagnetic dispersion successfully identified the observed eigenmodes. Stability analysis of the wave-plasma interaction resulted in a stability criterion predicting hysteresis loops in the power-density dependence, which were found in the experiment. A possibility of collisionless absorption of surface waves, i.e. mode conversion to electron plasma waves at the resonant layer, is discussed with the recent experimental results taken into account. From the plasma technology point of view, examples of surface-wave plasma tools (some of them commercially available) are introduced and the significance of the antenna structure is emphasized. Finally, the advantages of the surface-wave plasma source in comparison with other high-density sources are summarized.

In this work, oxygen-containing groups were introduced onto multiwall carbon nanotubes (MWCNTs) by using microwave-excited Ar/O 2 surface-wave plasma (SWP) treatment. The changes of the atomic contents and structure properties of MWCNTs as a function of gas flow rate, treatment time, and plasma power were analyzed using X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. A mechanism of MWCNT oxidation was proposed, based on XPS analysis, which showed how oxygen-containing groups, such as C-O, CdO, and O-CdO, were generated on the surfaces of MWCNTs. The surface morphology of MWCNTs was observed by field emission scanning electron microscopy (FE-SEM). The results indicated that Ar/O 2 plasma treatment greatly enhanced the content of oxygen, modified structure properties, induced more surface defects, and improved the dispersion of MWCNTs in aqueous solution. The integrity of the nanotube patterns was not damaged.