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1.Pleasedepicttheeffectsofionbambardmentintheprocessesoffilmgrowth.Effectsinfilmgrowth:1.Enhancementofadatomsurfacemobility2.Stimulationoftheearlystagesoffilmformation,e.g.,nucleation,growth,andcoalescence3.Developmentofpreferredcrystalorientation.4.Lowersubstratetemperaturesfortheonsetofepitaxy.5.Crystallizationofamorphousfilmsandamorphizationofcrystallinefilms6.Increasedfilm/substrateadhesion7.Modificationoffilmstress8.Stimulationoffilm-sorptioneffectsandfilmsurfacereactivityIonbombardmentofgrowingfilmsmodifiesatleastfourmeasurablecharacteristicsofitsstructure:(1)surfacetopographyandroughness,(2)crystallographyandtexture,(3)grainstructure,includinggrainsizeandmorphology,and(4)defectsandstress.SurfacetopographymodificationFilmsmoothingandimprovedcoverageofdepressions,corners,andstepsareenhancedbyresputtering.Whileionfluxinducedsurfacesmoothingoccursduringfilmgrowth,aninterestingrougheningofsurfacetopographyisobservedunderhigherionenergy.CrystallographyandtexturesInterplanarspacingsincrease.Filmsfrequentlydisplaypreferredorientation,orpreponderanceofcertainplaneslyingparalleltothesubstrateplane,inthepresenceofionbombardment.GrainstructureIonbombardmentgenerallycausesareductionoffilmgrainsize.CompositionalModificationofSurfacesCleanningsubstratesurface,sometimesincorporatinggasimpurity.DefectsandstressIonbombardmentgeneratesdefects,compressivefilmstressisgeneratedbystuffingsomeatomsintointerstitiallatticepositions.Athigherionenergytheionbombardmentpromotetheformationofamorphousstructure.Ion-beammixingDuringionbombardmentoftwo-ormultiple-componentfilmsystems,atomstendtomixcausingbothcompositionalandstructuralchange.Sucheffectsareextremelyefficientinpromotingadhesionoffilmstosubstrates.2.Pleasesummarizethedepositionmethods,properties,andapplicationofdiamondfilms.Methods:Microwaveplasma-assistedCVDHotfilament-assistedCVDRFplasma-assistedCVDDCplasma-assistedCVDElectroncyclotronresonancemicrowaveplasma-assistedCVDCombustionflame-assistedCVDPlasmajetCVDProperties:HighesthardnessHighestthermalconductivityHighsoundvelocityHighestelasticmodulusLagerbandgapLowestcompressibilityHighchemicalstabilitytoacidHighbreakdownvoltageLowthermalexpansioncoefficientApplications:Cuttingtools.ProtectivecoatingsThermalconductorOpticalwindowOpticalswitchElectronicdevicesfunctioningathightemperatures,voltages,power-levels,frequencies,andradiationenvironments.3.WhatisthedistinctionbetweenPVDfromCVD?AmongthefactorsthatdistinguishPVDfromCVDarethefollowing:(1)Relianceonsolidormoltensources,asopposedtogenerallygaseousprecursorsinCVD.(2)Thephysicalmechanisms(evaporationorcollisionalimpact)bywhichsourceatomsenterthegasphase(3)Areducedpressureenvironmentthroughwhichthegaseousspeciesaretransported.(4)Thegeneralabsenceofchemicalreactionsinthegasphaseandatthesubstratesurface(reactivePVDprocessesareexceptions)4.Thethinfilmmicrostructurescanbecontrolledbychangingdepositionconditions.Pleasediscussunderwhatconditionscanyoudepositamorphous,polycrystalline,andsinglecrystalthinfilmsinchemicalvapordepositionprocess.Thetwomostimportantfactorsaffectinggrowthstructuresarevaporsupersaturationandsubstratetemperature.Single-crystalfilmgrowthisfavoredbylowgassupersaturationandhightemperature,whereasamorphousfilmformationispromotedattheoppositeextremesofhighsupersaturationandlowtemperature.Intheintermediateconditionspolycrystallinefilmsform.Inprinciple,thefreeenergychange∆Gisthecriterion,smallnegative∆G:singlecrystalorepitaxial;largenegative∆G:amorphous,middlenegative∆G:polycrystalline.5.Pleasedescribetheprincipleofmagnetronsputteringaccordingtothefollowingfigure.p.156,157,223Keypoints:(1)Applicationofmagneticfieldparalleltothetargetsurfaceandperpendiculartotheappliedelectricalfield.Thisisrealizedbyarrangingsmallpermanentmagnetsonthebackofthetarget.Themagneticfieldlinesarchoverwithaportionparalleltothetargetsurface;(2)Theemittedelectronsareattractedbacktothetargetsurfaceandexecuteaperiodichopingmotionoverit;(3)Mostoftheelectronsareconfinedintheregionnearthetargetsurface;(4)Highplasmadensityisgeneratednearthetargetsurface;(5)Thesputterratesincreaseduetotheincreaseindensityofsputteringions.6.PleaseexplaintheworkingprinciplesofRotaryvanepump,Diffusionpump,andCryopump.p71,74,76Rotaryvanepump:Rotaryvanepumpismadeupofeccentricallymountedrotorandspring-loadedvanes,thegasfromthevacuumsystemisexpandedintothepumpandsealedoff,andthencompressedoutofthepumpexhaust.Diffusionpump:Itworksbasedonmomentumtransferbyvaporjetstream.Individualmoleculesarepushedtowardexhaustbyjetstream;hence,thepumpworksinthemolecularflowregimeCryopump:It’sgas-entrapmentpump.Thegasmoleculesareremovedfromgasphasebycondensationatlowtemperature.7.WhatisKnudsennumberKn?HowtodistinguishingbetweentheflowregimesaccordingKn?Knisdefinedbytheratioofthegasmeanfreepathtoacharacteristicdimensionofthesystem(e.g.,chamberorpipediameter,Dp),i.e.,Kn=λmfp/Dp.AccordingtoKnvaluetheflowrigimecanbeclassifyasfollowing:MolecularflowKn1Intermediateflow1Kn0.01ViscousflowKn0.018．(a)Pleasequantitativelydiscusswhyanegativeself