Optical thermal plasma generation

Thermal Plasma Generation in Microwave and Optical Discharges... 

Due to their isotropic radiation, LPP sources allow for the use of normal incident collectors thus, higher collection efficiency can be achieved with LLP sources as opposed to DPP sources, which tend to be directional. Because LPP sources do not require electrodes, there is no concern about electrode debris being generated from them. In addition, LLP sources have potential for easier and better thermal management than DPP sources because the plasma they generate is isolated from the collection optics, which is designed to capture the emission from the plasma and relay it to the intermediate focus from where it is relayed to the exposure tool. 

PVD processes typically use solid-state sources. The gas-phase species for thin-film deposition are generated from the source by thermal heating, electron beam evaporation, or sputtering. In CVD one or several gaseous precursors (gas mixtures) are activated to generate the reactive gas-phase species that forms the solid films. The precursor(s) are activated thermally ( standard CVD), within a plasma (plasma CVD), or by optical excitation (photo or laser CVD). 

The optical micrographs in Figure 5 show the effect of oxygen plasma exposure to pure nylon 6 and a nylon 6/7.5wt% layered silicate nanocomposite. Both are melt-processed samples recast from the 1,1,1,3,3,3-hexa-fluoro-2-propanol solution. The nylon 6 sample experiences almost complete deterioration after 8 hours (480 minutes) of continuous exposure. In contrast, deterioration of the nanocomposite is minimal, with no significant decrease in thickness. Buckling of the nanocomposite sample after exposure arises from differences in thermal expansivity of the self-generating ceramic surface and the bulk polymer nanocomposite. 

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