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1、JOURNALOFAPPLIEDPHYSICS108,1149092010SimulationsofchemicalvapordepositiondiamondfilmgrowthusingakineticMonteCarlomodelandtwo-dimensionalmodelsofmicrowaveplasmaandhotfilamentchemicalvapordepositionreactors1,a1112P.W.May,J.N.Harvey,N.L.Allan,J.C.Richley,andYu.A.Mankele
2、vich1SchoolofChemistry,UniversityofBristol,BristolBS81TS,UnitedKingdom2Skobel’tsynInstituteofNuclearPhysics,MoscowStateUniversity,Leninskiegory,Moscow119991,RussiaReceived23September2010;accepted15October2010;publishedonline9December2010Aone-dimensionalkineticMonteC
3、arloKMCmodelhasbeendevelopedtosimulatethechemicalvapordepositionofadiamond100surfaceunderconditionsusedtogrowsingle-crystaldiamondSCD,microcrystallinediamondMCD,nanocrystallinediamondNCD,andultrananocrystallinediamondUNCDÞlms.Themodelconsidersadsorption,et
4、ching/desorption,latticeincorporationandsurfacemigrationbutnotdefectformationorrenucleationprocesses.Twomethodshavebeendevisedforestimationofthegasphaseconcentrationsofspeciesatthegrowingdiamondsurface,andareusedtodetermineadsorptionratesforC1Hxhydrocarbonsforthediffe
5、rentconditions.Therateofmigrationofadsorbedcarbonspeciesisgovernedbytheavailabilityofneighboringradicalsites,which,inturn,dependupontheratesofHabstractionandofsurface-radicalmigration.TheKMCmodelpredictsgrowthratesandsurfaceroughnessforeachofdiamondtypesconsistentwith
6、experiment.Intheabsenceofdefectformationandrenucleationtheaveragesurfacediffusionlength,,isakeyparametercontrollingsurfacemorphology.When2,surfacemigrationislimitedbythelackofavailabilityofsurfaceradicalsites,andthemigratingsurfacespeciessimplyhopbackandforthbetwee
7、ntwoadjacentsitesbutdonottravelfarbeyondtheirinitialadsorptionsite.Thus,EleyÐRidealprocessesdominatethegrowth,leadingtotheroughsurfacesseeninNCDandUNCD.ThemaximumorÒintrinsicÓsurfaceroughnessoccursfornominallyzero-migrationconditions=0withanrmsvalueofapproximatelyÞ
8、vecarbonatoms.Conversely,whenmigrationoccursovergreaterdistances2,LangmuirÐHinshelwoodprocessesdominatethegrowthproducin