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1、SEMTest1.Q1:1.InmostCaSeSwhenX-rayspassthroughmattertheirintensitywi1.1.be.unchangedenhancedreducedcorrectedQ2:Inthisschematicdrawingofascanninge1.ectronmicroscope,which1.abe1.ingschemeiscorrect?(1)-e1.ectrongun(2)-backscatterede1.ectrondetector(3)-secondarye1.ectrondetector一samp1.eA=1,B=2,C=3A=1,B=
2、3,C=2A=2,B=3,C=1A=3,B=2,C=1Q3:WhereinsideanSEMistheBackscatteredE1.ectronDetector1.ocated?Be1.owthesamp1.eA1.1.aroundthesamp1.eImmediate1.ybe1.owtheobjective1.ensCanbeinsertedwithintheSEMco1.umninanypositionQ4:Thepictureaboveshowsamixedminera1.sandfromDunwichthathavebeendustedontoanadhesivecarbontab
3、,coatedwithcarbonandimagedontheJSM64601.Ausingoneofthebackscatterdetectormodes.Basedonthisdataandyourknow1.edgeofcompositiona1.backscatterede1.ectronimages,whichisthemost1.ike1.ycorrectorderforthe31.abe1.1.edpartic1.esiftheyarerankedfromhighestaverageatomicnumberto1.owestatomicnumber.C1；2;33:2;12;3,
4、11；3;23;1;2Q5:Whatisthemostcommon1.yusednamefortheine1.asticscatteringprocesswherebyprimarybeame1.ectronsknockoutothere1.ectronsfromtheirshe1.1.s?rInner-she1.1.ionizationX-rayionizationInnere1.ectronemissionInner-she1.1.X-rayemissionQ6:Whenahighvo1.tagee1.ectronbeamstrikesaspecimen,howismostoftheene
5、rgydispersed?rX-raysHeatcSecondarye1.ectronsBackscatterede1.ectronsQ7:Thee1.ectronbeamcreatesaninteractionvo1.umeinasamp1.e.WherearetheX-raysgeneratedfromwithinthisvo1.ume?Very1.ightElementsMediuman( Heavy E1.cmcatthesurfaceon1.yinthethintop1.ayer(b1.ack1.ayer)on1.yinthemidd1.e(grey)1.ayeron1.ythrou
6、ghouttheentireinteractionvo1.umeinthe1.owerregion(whitearea)on1.yQ8:What1.abe1.ingschemeoftheSEMshowninthisphotographiscorrect?1.Secondarye1.ectrondetector2.X-raydetector3.Specimenchamber4.O1.apertureA=1,B=2,C=3,D=4A=1,B=2,C=4,D=3A=2,B=3,C=4,D=1A=2,B=4,C=3,D=1Q9:Whatisthereasonforusings1.owscanrates
7、toaccumu1.atemicrographs?Thee1.ectronbeamismorestab1.eThesigna1.-to-noiseratioisimprovedThereso1.utionisenhancedtThereistimetogetadrinkofwaterQ1Thebestwaytoconductexperimentsandgetresu1.tsusingaSEMis?O:Toknowaboutthetechnique,thetheory,theprocedures,howtopreparethesamp1.esandaskthetechniciantodothee
8、xperimentsbecauseaScientistjustneedtointerpretresu1.tsanddoesntneedtodirect1.yconductexperiments-Toknowaboutthetechnique,thetheory,theprocedures,andaskthetechniciantopreparethesamp1.esbecauseaScientistjustneedtointerpretresu1.tsanddirect1.yconductexperimentsbuthasnotimetospendpreparingroutinesamp1.e
9、sHaveameetingwiththetechnicianandcarefu1.1.yexp1.ainhim/hera1.1.theparticu1.arsoftheexperimentandaskforadetai1.edfina1.reportinc1.udinga1.1.dataandinstrumentworkingconditions1.Askthetechniciantodotheexperimentswhi1.eyouaresittingnearbytakingnotesand1.earninghowtoswitchonandoffbuttonsdependingonwhaty
10、ouwanttogetToknowaboutthetechnique,thetheory,theprocedures,howtopreparethesamp1.esandconductyourexperimentaskingthetechnicianifyouhavesomedoubtsQ1Howwou1.dyoubestprepareaconductivesamp1.eoffinepartic1.es(e.g.apowderedmeta1.)1:forroutinebackscatterede1.ectronimagingoftheinterna1.structure.dustontoana
11、dhesivecarbontabandcoatwithp1.atinumdustdirect1.yontoanA1.stubandcoatwithcarbonstabi1.iseinresin(e.g.epoxy),po1.ishtoaf1.atsurfaceandcoatwithcarbonstabi1.iseinepoxyresin,po1.ishtoaf1.atsurfaceanddonotcoatQ1Approximate1.yhow1.ongdoesanatomremainsionized?2:1 Unti1.theexperimentisfinished(1OOseconds)An
12、atomthathasbeenionizedwi1.1.nevergainbacktoitsorigina1.conditionsCForaveryshorttime,intheorderof10,4secondsItdependswhichenergiesareinvo1.vedbuta1.waysintheorderofIO_3secondsUnti1.aneighbouringatomhasane1.ectronavai1.ab1.etorep1.acetheejectedoneQ1Atypica1.morpho1.ogica1./topographica1.SEMimageisgene
13、ratedbyco1.1.ectingthewhich3: e1.ectronsthatcomeoffthesamp1.esurface?backscatterede1.ectronse1.astica1.1.yscatterede1.ectronstprimarybeame1.ectronssecondarye1.ectronsQ1Whichconditionswou1.dbemostfavourab1.efortheco1.1.ectionofbackscatterede1.ectron4:imagesfromaninsu1.atingsamp1.e.15kVprimarybeam,go1
14、.dcoatedsamp1.e15kVprimarybeam,carboncoatedsamp1.e3kVprimarybeam,go1.dcoatedsamp1.e3kVprimarybeam,uncoatedsamp1.eQ1Toachieveafocussedimagethee1.ectronbeammustbebroughttoafinespotpositionedat5:thesurfaceofthesamp1.e.Thedevicedirect1.yresponsib1.eforthisis:thecondensor1.enstheobjective1.enstheStigmata
15、torcoi1.sr.1thescancoi1.sQ1Whene1.ectronsinteractwithaso1.idtheycreateaninteractionvo1.ume.Whichsigna1.sare6:producedintheinteractionvo1.ume?Augere1.ectronsandcharacteristicX-raysCharacteristicX-raysandsecondarye1.ectronstSecondarye1.ectronsandAugere1.ectronscA1.1.oftheaboveQ1Whyarespecimenssometime
16、scoatedwithgo1.dorp1.atinumbeforemicroscopy?7:(Tomakethesurfacesmoothertoyie1.dbetterimagesTomakethemva1.uab1.esostudentswi1.1.not1.osethemToimprovetheyie1.dofsecondarye1.ectronsToinhibittheproductionofbackscatterede1.ectronsQ1OnceanEDSX-rayspectrumhasbeengeneratedwe1.ookattheofthe8: peakstodetermin
17、etheactua1.e1.ementsinvo1.ved.heightrwidthCPSenergyfu1.1.widthha1.fmaximumQ1Whatconditionwou1.dresu1.tinahigherreso1.utionbackscatterede1.ectronimages?9:Higheracc1.eratingvo1.tageShorterworkingdistanceHigheratomicnumbersamp1.eCoatingthesamp1.eQ2HowisworkingdistancedefinedintheSEM?O:Theseateddistance
18、betweenthemicroscopistandthemicroscopeThedistancefromthespecimentothesecondarye1.ectrondetectorThedistancefromthespecimentotheobjective1.enspo1.epieceThedistancefromthespecimentoX-raydetectorQ2Whatisthemost1.ike1.yeffectthatreducingthee1.ectronprobesizehasonabackscattered1:e1.ectronimage?CT1Improver
19、eso1.utionEnhancethesigna1.-to-noiseratiofDegradethesigna1.-to-noiseratioNoeffectQ2WhatcoatingtypeispreferredforcarryoutenergydispersiveX-rayana1.ysisona2:conductingspecimen?Go1.dcoatingNocoatingCarboncoatingP1.atinumcoatingQ2StartingfromthetophowisanSEMco1.umnorganised?3:a,Cathode;b,Anode;c,Whene1.
20、tcy1.inder;d,Condenser1.ens;e,Samp1.e;f,Objective1.ens;a,Cathode;b,Whene1.tcy1.inder;c,Anode;d,Samp1.e;eObjective1.ens;fCondenser1.ens;a,Cathode;b,Whene1.tcy1.inder;c,Anode;d,Condenser1.ens;eObjective1.ens;f,Samp1.e;厂a,Cathode;b,Whene1.tcy1.inder;c,Anode;d,Objective1.ens;esamp1.e;f,Condenser1.ens;a,
21、Cathode;b,Condenser1.ens;c,Whene1.tcy1.inder;d,Anode;eObjective1.ens;f,Samp1.e;Q2MagnificationisadirectprocessinanSEM.Increasedmagnificationistheresu1.tofthe4:samp1.eareascannedbythebeambeing:scannedmorerapid1.yscannedmores1.ow1.yincreasedinsizedecreasedinsizemovedfurtherfromthebottom1.ens.Q2Ifyours
22、amp1.eisaninsu1.atorandacarboncoatingisneededthecoatingfi1.mshou1.dbe:5:.FpositionsFewmmthicktoensurethatsamp1.esurfacewi1.1.notadsorbmoistureandwatermo1.ecu1.esFewtensofnmthickandhomogeneousFewtensofnmthickandjust1.ocatedoverthesamp1.epartsofinterestQ2Whiche1.ectronsourceprovidesthegreatestbrightne
23、ss?6:CEtungstenfi1.ament1.aB6crysta1.co1.dfie1.demissionhotfie1.demissionQ2Howwou1.dyouprepareafine1.ypowderedsamp1.eforsecondarye1.ectronimaging?7:Pourontoana1.uminumspecimenstubfEmbedinconductingcarbontape厂G1.uetoag1.asss1.ideStabi1.izeinepoxyQ2Whyischi1.1.edwatersupp1.iedtothescanninge1.ectronmic
24、roscope?8:tokeeptheroomcoo1.tokeepthee1.ectromagnetic1.ensescoo1.tokeepthesamp1.ecoo1.,tokeeptheaperturescoo1.Q2Forwhichexperimentsisitessentia1.thatspecimensarefine1.ypo1.ished?9:Backscatterede1.ectronimaging,Secondarye1.ectronimaging1.owvacuume1.ectronmicroscopyHighreso1.utione1.ectronmicroscopyQ3
25、Insecondarye1.ectronimagingwhichaspectofthesamp1.ewi1.1.bedominantindeterminingO:theappearanceoftheimage?cCDensityAverageatomicnumber(SurfaceroughnessA1.1.oftheaboveSEMTest1.Q1:WhatcoatingtypeispreferredforcarryoutenergydispersiveX-rayana1.ysisonaconductingspecimen?(Go1.dcoatingNocoatingtCarboncoati
26、ngP1.atinumcoatingQ2:Whiche1.ectronsourceis1.eastappropriateforenergydispersiveX-rayana1.ysis?(Tungstenfi1.amentr1.aB6Co1.dfie1.demission(Hotfie1.demissionQ3:Theimagebe1.owisofaNaCIsa1.tcrysta1.Whatmodeofimagingismost1.ike1.ytohavebeenusedtogeneratethismicrograph?Cathodo1.uminescenceBackscatterede1.
27、ectronsSecondarye1.ectronsAugere1.ectronsQ4:Whatisthecorrect1.abe1.ingforthis1.aB6e1.ectrongunassemb1.y?A-e1.ectronemitter,B-Wehne1.t,C-e1.ectrodeA-Wehne1.t,B-e1.ectrodeemitter,C-e1.ectrodeA-e1.ectrode,B-Wehne1.t,C-e1.ectrodeemitterNoneoftheaboveQ5:Toachieveafocussedimagethee1.ectronbeammustbebrough
28、ttoafinespotpositionedatthesurfaceofthesamp1.e.Thedevicedirect1.yresponsib1.eforthisis:thecondensor1.enstheobjective1.enstheStigmatatorcoi1.sthescancoi1.sQ6:Forwhichexperimentsisitessentia1.thatspecimensarefine1.ypo1.ished?Backscatterede1.ectronimagingSecondarye1.ectronimaging1.owvacuume1.ectronmicr
29、oscopyHighreso1.utione1.ectronmicroscopyQ7:Whatisthemostcommon1.yusednamefortheine1.asticscatteringprocesswherebyprimarybeame1.ectronsknockoutothere1.ectronsfromtheirshe1.1.s?Inner-she1.1.ionizationX-rayionizationInnere1.ectronemission.-Inner-she1.1.X-rayemissionQ8:Whymustscanninge1.ectronmicroscope
30、soperateundervacuum?Topreventsamp1.esfromdegradingToa1.1.owe1.ectronstopropagatewithoutscatteringTopreventthee1.ectromagnetic1.ensfromheatingupA1.1.oftheaboveQ9:Theinteractionvo1.umesforavarietyofSEMacce1.eratingvo1.tagesandmateria1.sareshown.Whichschematicdrawingrepresentsthehighestacce1.eratingvo1
31、.tageand1.owestaverageatomicnumber?Q1Ifyoursamp1.eisaninsu1.atorandacarboncoatingisneededthecoatingfi1.mshou1.dbe:0:1.FpositionsFewmmthicktoensurethatsamp1.esurfacewi1.1.notadsorbmoistureandwatermo1.ecu1.esFewtensofnmthickandhomogeneousFewtensofnmthickandjust1.ocatedoverthesamp1.epartsofinterestQ1Th
32、ee1.ectrontransitionbe1.owwi1.1.emitacharacteristicX-ray.Whattypeoftransitionis1:shown?M-She1.1.1.-ShellK-ShellQ1Thehighreso1.utionsecondarye1.ectronimageaboveisofadiatomimagedat50000Xat2:5mmworkingdistancewiththeJSM6400FFie1.demissionSEM.BasedonyourunderstandingoftheSEMparametersrequiredforsuchimag
33、es,whatwou1.dbethemost1.ike1.ysettingsforthespotsizeandtheobjective1.ensaperture.sma1.1.diameterspot;1.argediameteraperture1.argediameterspot;sma1.1.diameteraperture1.argediameterspot;1.argediameteraperturesma1.1.diameterspot;sma1.1.diameterapertureQ1TheSEMimagesaregeneratedbyscanningthebeamoverthes
34、amp1.esurfaceand3:co1.1.ectingthesigna1.sderivedfromthesamp1.e-beaminteractions.WherewithintheSEM,areyou1.ike1.ytofindthebeamscanningcoi1.s?Immediate1.ybe1.owthegunImmediate1.ybe1.owthecondenser1.ensesWithintheobjective1.ensArecoup1.edwiththeanodeQ1Whattypeof1.ensesareusedintheSEMco1.umninordertofoc
35、usthee1.ectronbeam?4:re1.ectrostaticcoptica1.c,.astigmaticc1e1.ectromagneticQ1Howwou1.dyoubestprepareaconductivesamp1.eoffinepartic1.es(e.g.apowderedmeta1.)5:forroutinebackscatterede1.ectronimagingoftheinterna1.structure.dustontoanadhesivecarbontabandcoatwithp1.atinumdustdirect1.yontoanA1.stubandcoa
36、twithcarbonstabi1.iseinresin(e.g.epoxy),po1.ishtoaf1.atsurfaceandcoatwithcarbonstabi1.iseinepoxyresin,po1.ishtoaf1.atsurfaceanddonotcoatQ1Whenahighvo1.tagee1.ectronbeamstrikesaspecimen,howismostoftheenergy6:dispersed?cX-rayscHeatSecondarye1.ectronsBackscatterede1.ectronsQ1Whatistherangeofenergiesfor
37、SecondaryE1.ectrons?7:r2-50eV50-100eV0-2eVIOOOeVQ1Whatisthemost1.ike1.yeffectthatreducingthee1.ectronprobesizehasonabackscattered8:e1.ectronimage?Improvereso1.utiontEnhancethesigna1.-to-noiseratioDegradethesigna1.-to-noiseratiotNoeffectQ1Forhighreso1.utionsecondarye1.ectronimagingwhichobjective1.ens
38、aperturesizeis9:preferred?1.argeMediumrSma1.1.tNoneQ2Whatistheprimaryreasonforthescanninge1.ectronmicroscopestobeab1.etoobserve0:sma1.1.erfeaturesthananoptica1.microscope?Scanninge1.ectronmicroscopeshaveasuperior1.enssystemresu1.tinginasma1.1.erprobeThe1.ongerwave1.engthofe1.ectronsenab1.ethegenerat
39、ionofsma1.1.erprobesizesintheSEMTheshorterwave1.engthofe1.ectronsenab1.ethegenerationofsma1.1.erprobesizesintheSEM.*.ThespecimenpreparationusedforSEMresu1.tsinbetterreso1.utionQ2Whiche1.ectronsareusedtocreateimageswherecontrastisproportiona1.toaverageatomic1:number?Absorbede1.ectronsBackscatterede1.
40、ectronsSecondarye1.ectronsSurfacee1.ectronsQ2Whatisthereasonforusings1.owscanratestoaccumu1.atemicrographs?2:Thee1.ectronbeamismorestab1.eThesigna1.-to-noiseratioisimprovedThereso1.utionisenhancedtThereistimetogetadrinkofwaterQ2StartingfromthetophowisanSEMco1.umnorganised?3:a,Cathode;b,Anode;c,Whene
41、1.tcy1.inder;d,Condenser1.ens;e,Samp1.e;f,Objective1.ens;a,Cathode;b,Whene1.tcy1.inder;c,Anode;d,Samp1.e;eObjective1.ens;fCondenser1.ens;a,Cathode;b,Whene1.tcy1.inder;c,Anode;d,Condenser1.ens;eObjective1.ens;f,Samp1.e;a,Cathode;b,Whene1.tcy1.inder;c,Anode;d,Objective1.ens;esamp1.e;f,Condenser1.ens;厂
42、a,Cathode;b,Condenser1.ens;c,Whene1.tcy1.inder;d,Anode;eObjective1.ens;f,Samp1.e;Q2WhereinsideanSEMistheBackscatteredE1.ectronDetector1.ocated?4:r，Be1.owthesamp1.e(A1.1.aroundthesamp1.etImmediate1.ybe1.owtheobjective1.ensCanbeinsertedwithintheSEMco1.umninanypositionQ2Whiche1.ectronsareusedtocreateim
43、ageswherecontrastisproportiona1.toaverage5:atomicnumber?absorbede1.ectronsbackscatterede1.ectronssecondarye1.ectronssurfacee1.ectronsQ2Whatisthecharacteristicofaspecimenwhichhasbeencoatedwithago1.d1.ayerthatistoo6:thick?It1.ooksgo1.dinco1.our(Thesecondarye1.ectronimageisnotchargingThesecondarye1.ect
44、ronimageischargingThesecondarye1.ectronimageappearscrackedoriscoveredbynodu1.esQ2Inthevacuumsystemofatypica1.fie1.demissionSEMsuchastheJSM6400Fthetypica1.7:seriesofvacuumpumpsinthevacuumsystemis,startingfromatmosphericpressure(air),intheorder:rotarypump;hotoi1.diffusionpump;ionpumprotarypump;ionpump
45、;hotoi1.diffusionpumphotoi1.diffusionpump;rotarypump;ionpumpionpump;rotarypump;hotoi1.diffusionpumphotoi1.diffusionpump;ionpump;rotarypumpQ21.InmostCaSeSwhenX-rayspassthroughmattertheirintensitywi1.1.8:be.runchangedenhancedreducedcorrectedQ2Whichconditionswou1.dbemostfavourab1.efortheco1.1.ectionofb
46、ackscatterede1.ectron9:imagesfromaninsu1.atingsamp1.e.15kVprimarybeam,go1.dcoatedsamp1.e15kVprimarybeam,carboncoatedsamp1.e3kVprimarybeam,go1.dcoatedsamp1.e3kVprimarybeam,uncoatedsamp1.eQ3Whyarespecimenssometimescoatedwithgo1.dorp1.atinumbeforemicroscopy?0:Tomakethesurfacesmoothertoyie1.dbetterimagesTomakethemva1.uab1.esostudentswi1.1.not1.osethemToimprovetheyie1.dofsecondarye1.ectronsfToinhibittheproductionofbackscatterede1.ectronsSEMTest1.Q1:Formoste1.ementstheprimaryX-raysmeasuredareformedbyionizationoftheatomsthatproducethem.innershe1.1.midd1.esh
