低温等离子体表面处理技术

低温等离子体表面处

理技术PlasmaandfirstwallIntroductionTodayIwilltalkaboutsomethingaboutmystudyonthefirstwallinthetokamak.Firstly,Iwillshowyouthatwhattheplasmaisinourlifethoughtthefollowingpicturessuchas:Fig.1LighningFig.2AuroraFig.3AstrospaceJustasthepicturesmentionedabove,theyareallconsistofplasma.But,whatdoeshaveintheplasma,nowourscientisthadgivenadefinitionthattheplasmastateisoftenreferredtoastheourthstateofmatterandcontainsenoughfreechargedparticles(negativeions、positiveions)andelectronics.Likethephotobelow.Fig.4PlasmaproductionPlasmaproductionInourresearch,weproducetheplasmathroughanICP(inductivelycoupledplasma)

deviceasfollow：ThroughtheRF(radiofrequency)sourcepowergeneratorandmatchingbox,wewillgettheplasmaweneedintheexperiment.TheFig.6showsustheplasmaproducedbytheRFsource.Fig.6TheICPplasmaPlasmadiagnosisAndthenweneedtodiagnosetheplasmacharacteristicsthroughsomemethodslikespectrumandprobe.Fig.7TheplaneprobeWeusedtheplaneprobetodetectionthetemperatureofelectronicsandthedensityoftheplasmaastheFig.8andFig.9.

Powcr(W)1.Ainfiirigthe|Hiv*ernf300(^800(1**.11・史甘Powcr(W)1.Ainfiirigthe|Hiv*ernf300(^800(1**.11・史甘1・利力自eill"■'civiic171・击心喏广商[◎广看11$n<it2xAtthepre^KiireofOsSSKPa,.IIherHii?clroniiCtemperatrueuoiniieupnb^iouFig.8electronictemperature*Te(r^~M0--l2Pa^■Te(c^_Tej£VML59Pii)LU-VoltagcValtWHr(v)i(<lP42)、qltase(^)(0.827)VoltageLU-VoltagcValtWHr(v)i(<lP42)、qltase(^)(0.827)Voltage4%)(1.2)XpltaecBower(W)Fig.9Plasmadensityd.E)4±音赵胃5E£1liepdriicaldensityis注l/oirmreandnnnarcRefcirethenT0.42Pai,tliepsirtic^iildensityis-ri^iiiti'^a，theincreaseoftliepre^sure.Ukiflthepartiicalldensityisdropped,aflcrIlirprcsMircof(J..42PHu.IntheFig.9,wecanconfirmthatastherisingofthepower,theparticledensityisalsomoreandmorehigh.Andbeforethepressureof0.42Pa,theparticlesdensityisrisingastheincreaseofthepressure.Buttheparticlesdensityisdroppedafterthepressureof0.42Pa.AndthanweusedthespectrographtodetectiontheparticlesofhydrogenastheFig.11shownus.

Fig.10ThePIspectrograph(.11■曲1134UIFig.10ThePIspectrograph(.11■曲1134UIPower(KW)Fig.11ThehydrogenspectrumWefindthatastheincreasingofthepower,therearefourcurvesoccurred.Butwhenthepowerreachstoabout2000wand4000w,theHaHphaveacapacity.Whenwehaveaclearknowaboutthecharacteristicsoftheplasma.WeusetheplasmatodealwiththefirstwallmaterialssuchasW(tungsten).PlasmainteractionwiththefistwallInourexperiments,weputtheWintheplasma,andacceleratetheHe)articlesorH+usingastaticelectricfieldsothattheycanownapowerfulenergytointeractionwiththematerials.Intheexperiments,wechoicethedifferentpowerfulparticlestodealwiththeW.Andaftertheexperiment,weusedSEMtoanalyzethesurfaceofthematerials.ThesurfaceoftheWcanbeclearlyobservedthathavegrownsomenanostructurethroughtheSEMliketheFig.12.Fig.12SEMimagesofsamplesexposedtoameanionicfluxof1.28E22ion/m2/swithheliumfluencewas1.0E26m_2andanionincidentenergywas(A)10eV、(B)20eV、(C)50eVtheSEMliketheFig.12.Fig.12SEMimagesofsamplesexposedtoameanionicfluxof1.28E22ion/m2/swithheliumfluencewas1.0E26m_2andanionincidentenergywas(A)10eV、(B)20eV、(C)50eV、(D)100eV、(E)400eV、(F)600eV.Fig.13Cross-sectionalSEMmicrographofthesamplesshowninFig.12,respectivelyTheFig.13showusthecross-sectionalSEMmicrographofthesamples,wecanseethattherearemanynanostructureformedonthesurfaceoftheW.Andthenanostructurecangrowupastheparticlesownhigherenergy.Fig.14Cross-sectionalSEMmicrographofCircularRegion,shownintheFig.13(f)Butinourexperiments,wefindadifferentphenomenonwhentheparticleshaveapowerfulenergyabout600eVtherearemanyswellonthesurfaceoftheW.Andthroughthecross-sectionalwecanseetheyarehollowintheswell.ConclusionInourresearch,wehavemainthreestepsasfollow:Firstly,webuildadevicetoproducetheplasmaweneed.Secondly,wediagnosedthecharacteristicsoft