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DCandRFglowdischargesByWenQiLU9/19/2005Contentsinlastlecture¾(forcoldplasma,thetemperaturesaredifferentforions,electronsandneutralparticals)¾¾Bohm¾¾(forthetypicalDCglowdischargeplasma,ωeisinGigahertzorderwhileωiisinmegahertzorder)2/120)(enkTeeDελ=2/1)()0(iemkTueiieeidDDDκκκκ++=2/102)(εωiimne=)(9000)(2/102Hznmneee≈=εω—)1lnln(γAPdBPdVs=VsPdABγPdVsAstonFaradaybriefsummary¾a¾ab¾bcac¾cd¾*AC1C2C1C2dElectronswithinthisplasmaareconstantlybeingrepelledwhenapproachingthehollowcathodewalls:Anoscillatorymotionoftheelectronsresultsyieldinggreatlyimprovedionizationratesandtherebyhigherplasmadensities*100~104Hz~1MHz1~100MHzγf1f2(f1f2)f1f2(f1f2)ff1ff213.56MHzt=0Va=-1000V,CC‘,Vb≈VaVb≈-1000Vt=0C‘0tT/2CVb-800V,Vb–Va=200VVb→-800V0tT/2C‘+++t=T/2Va+1000V,C–200V,Vb=1200VVb=1200Vt=T/2C‘Va=1000VT/2tTCVb+100VVb–Va=-900VVb→+100VT/2tTC‘eeet=TVa-1000VC900V,Vb=-1900VVb≈-1900Vt=TC‘VaV≈-1000Vsummary¾¾—¾¾Appendix: