核-壳结构PS C eO 2复合磨料的制备及其氧化物化学机械抛光性能

核-壳结构PSCeO2复合磨料的制备及其氧化物化学机械抛光性能摘要：本文采用一种简单的溶胶-凝胶方法制备了核-壳结构的PSCeO2复合磨料，通过SEM、XRD、FTIR等手段对其结构和性能进行了表征。研究结果表明，所制备的复合磨料具有明显的核-壳结构，CeO2与PS颗粒加强相互作用，CeO2的表面包覆了一层聚合物壳，使得复合磨料的密度增大，稳定性提高，摩擦磨损性能也得到了显著的提升。氧化物化学机械抛光实验表明，经过优化制备条件的核-壳结构PSCeO2复合磨料具有良好的抛光效果，对硅片表面的微观不平整度和表面光洁度有明显的提升，可以应用于半导体、光学和微电子等领域。

关键词：核-壳结构；PSCeO2复合磨料；氧化物化学机械抛光；半导体；光学；微电子

Introduction:

Withtherapiddevelopmentofthesemiconductor,opticalandmicroelectronicsindustries,thedemandforhigh-precisionpolishingtechnologyhasbecomeincreasinglyurgent.Amongthem,oxidechemicalmechanicalpolishing(CMP)technologyhasbecomeawidelyusedprocessingmethodduetoitsadvantagesoflowdamage,highefficiencyandhighstability.Thequalityofthepolishingprocessdependsnotonlyonthepolishingslurry,butalsoontheabrasiveparticlesusedintheslurry.

Inrecentyears,researchershavedevelopedcore-shellstructurecompositeabrasivestoimprovethepolishingpropertiesoftheabrasive.Duetotheuniquecore-shellstructure,thecompositeabrasivehasbetterstability,surfaceactivityandcompatibilitywiththematrix,whichprovidesanewapproachforimprovingthepolishingperformanceoftheabrasive.

Theaimofthepresentstudyistoprepareacore-shellstructuredPSCeO2compositeabrasivebysol-gelmethodandinvestigateitsoxidechemicalmechanicalpolishingperformance.

ExperimentalSection:

ThePSCeO2compositeabrasivewassynthesizedbyasol-gelmethod.Polystyrene(PS)microsphereswereusedasthecore,andceriumoxide(CeO2)nanoparticleswereusedastheshell.ThePSmicrosphereswerefirstmodifiedbysurfaceoxidationwithpotassiumpermanganateandthendispersedindeionizedwaterbyultrasonictreatment.TheCeO2nanoparticlesweredispersedinethanolbyultrasonictreatmentandthenmixedwithasuitableamountofsilanecouplingagentAPTES.ThemixedsolutionwasslowlydroppedintothePSmicrospheredispersionunderstirring,andthesystemwasstirredfor24htoobtainthePSCeO2compositeabrasive.

TheobtainedcompositeabrasivewascharacterizedbySEM,XRDandFTIR.TheoxidechemicalmechanicalpolishingexperimentswerecarriedoutonaBuehlerpolishingmachineusingaSiwaferasthesubstrate.Thepolishingparameterswereoptimized,andthepolishingperformancewasevaluatedbysurfaceroughness,surfacetopography,andremovalrate.

ResultsandDiscussion:

TheSEMimagesofthePSCeO2compositeabrasiverevealedthecore-shellstructureofthecompositeparticles.TheCeO2nanoparticlesweredistributedonthesurfaceofthePSmicrospheresandformedauniformshelllayer,increasingtheparticlesizeandstabilizingtheparticles.TheXRDandFTIRspectraindicatedthepresenceofCeO2andPSinthecompositeabrasive,andthePSCeO2compositeabrasivehadbettercompatibilityandstability.

TheoxidechemicalmechanicalpolishingexperimentsshowedthatthePSCeO2compositeabrasivehadbetterpolishingperformancethanpureCeO2abrasive.Undertheoptimalconditions,thesurfaceroughnessandsurfacetopographyoftheSiwaferweresignificantlyimproved,andtheremovalratewasalsogreatlyincreased.

Conclusion:

Acore-shellstructuredPSCeO2compositeabrasivewassuccessfullysynthesizedbysol-gelmethod.Thecompositeabrasivehasbetterstability,compatibilityandpolishingperformancethanpureCeO2abrasive.ThePSCeO2compositeabrasivehasgreatpotentialforapplicationinthefieldsofsemiconductor,opticalandmicroelectronics.Inconclusion,thesynthesisofcore-shellstructuredPSCeO2compositeabrasivesbysol-gelmethodoffersapromisingapproachforimprovingthepolishingperformanceofabrasiveparticles.TheobtainedcompositeabrasiveshavebetterstabilityandcompatibilitywiththematrixcomparedtopureCeO2abrasive,andthecompositeparticlesshowasignificantimprovementinpolishingperformance.ThePSCeO2compositeabrasivehasgreatpotentialforapplicationinthesemiconductor,opticalandmicroelectronicsindustriesduetoitsgoodpolishingproperties.Furthermore,thesol-gelmethodusedtosynthesizethecompositesisasimpleandeffectivemethodthatcanbeeasilyscaledupforindustrialproduction.Futureresearchcanfocusontheoptimizationofthecompositeabrasivepropertiesbyadjustingthecompositionandstructureoftheparticles.Overall,thisstudyprovidesnewinsightsintothedevelopmentofhigh-performanceabrasivesfortheoxidechemicalmechanicalpolishingprocess.Furthermore,thecore-shellstructureofthePSCeO2compositeabrasivescanbefurtheroptimizedbycontrollingthethicknessanddensityoftheshelllayer.Theshellthicknessanddensitycansignificantlyaffectthepolishingperformanceoftheparticles,astheycaninfluencethecontactareabetweentheabrasiveandthesubstratesurfaceduringpolishing.Therefore,moreresearchcanbeconductedtoinvestigatetheeffectofshellthicknessanddensityonthepolishingpropertiesofthecompositeabrasives.

Inadditiontothecore-shellstructure,theparticlesizeofthecompositeabrasivesalsoplaysanimportantroleindeterminingtheirpolishingperformance.Smallerparticlesizeusuallyleadstobettersurfacequalityandhigherpolishingefficiency.Therefore,thesol-gelmethodcanalsobeusedtocontroltheparticlesizeofthecompositeabrasives,whichcanfurtherenhancetheirpolishingproperties.

Furthermore,thePSCeO2compositeabrasivescanalsobemodifiedwithdifferentfunctionalgroupstoimprovetheirchemicalandphysicalproperties.Forinstance,theadditionofhydrophobicfunctionalgroupscanenhancethedispersibilityandstabilityofthecompositeparticlesinthepolishingslurry,whichcanimprovethepolishinguniformityandreducethedefectdensityonthepolishedsurface.

Overall,thedevelopmentofPSCeO2compositeabrasivesbysol-gelmethodholdsgreatpotentialforimprovingthepolishingperformanceofabrasiveparticlesintheoxidechemicalmechanicalpolishingprocess.Futureresearchinthisareacanfocusonoptimizingthestructure,particlesize,andsurfacemodificationofthecompositeabrasivestofurtherimprovetheirpolishingpropertiesandexpandtheirapplications.Anotheraspectoffutureresearchcanfocusoninvestigatingtheinteractionsbetweenthecompositeabrasivesandthepolishingpad,asthiscangreatlyaffectthepolishingperformanceandsurfacequalityofthepolishedsubstrate.Thesurfacepropertiesofthepolishingpad,suchasitssurfaceroughnessandporosity,caninfluencethefrictionalforcebetweentheabrasiveparticlesandthesubstrate,whichcanaffectthepolishingrateanduniformity.Therefore,thedevelopmentofasuitablepolishingpadforusewithPSCeO2compositeabrasivescanbeexploredtooptimizethepolishingprocess.

Moreover,thesol-gelmethodcanbeextendedtothesynthesisofothercompositeabrasives,suchasPSTiO2,PSAl2O3,andPSSiO2,toexpandtherangeofmaterialsthatcanbeusedinthechemicalmechanicalpolishingprocess.Inaddition,compositeabrasiveswithdifferentshapes,suchasrodsorfibers,canalsobesynthesizedusingsol-gelmethod,whichcanprovidenewstrategiesforpolishingcomplexsurfacesorstructures.

Lastly,theeffectofenvironmentalfactorssuchastemperatureandpHontherheologicalpropertiesandstabilityofthepolishingslurrycontainingthecompositeabrasivescanbeinvestigatedtodevelopmorestableandefficientpolishingslurries.Thiscanhelptoreducetheprocessingtimeforpolishingandimprovethecost-effectivenessoftheprocess.

Inconclusion,thesol-gelmethodhasbeenshowntobeapromisingapproachforthesynthesisofPSCeO2compositeabrasiveswithsuperiorpolishingperformance.Theextentofitsapplicationcanbeexpandedbyfurtheroptimizingtheparticlestructure,size,andsurfacemodification,aswellasexploringtheuseofothercompositeabrasivesandpolishingpads.Thechemicalmechanicalpolishingprocesscanthusbefurtherenhancedbyutilizingtheseinnovativeapproaches.Anotherareaforfutureresearchinthefieldofsol-gelsynthesizedcompositeabrasivesisexaminingtheiruseindifferentindustries,suchasintheoptical,semiconductor,andbiomedicalindustries.TheabilityofPSCeO2compositeabrasivestoachievehigh-qualitypolishingwithminimalsurfacedamagemakesthempotentialcandidatesforpolishingopticallensesandsemiconductordevices.

Furthermore,thebiocompatibilityandlowcytotoxicityofceriumoxidemakePSCeO2compositeabrasivesapromisingmaterialforbiomedicalapplications,suchaspolishingd