Audio frequency plasma

The cold plasma is most often generated in laboratories and industry by an electric glow discharge xmder low pressure using various frequencies of the applied electric field audio frequencies (AF, mainly in the range of 10-50 kHz), radio frequencies (RF, mainly 13.56 MHz), and microwave frequencies (MW, mainly 2.45 GHz). Sometimes, a direct current (DC) discharge is also used. An example of typical parallel plate plasma reactor, one of those being used in our laboratoiy for deposition of thin films, is sketched in Fig. 2. 

Tyczkowski, J. (1999). Audio-Frequency Glow Discharge for Plasma Chemical Vapor Deposition from Organic Compounds of the Carbon Family. /. Vac, Sci, Technol, A, Vol. 17, pp. 470-479... 

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