Field Ion Microscopy of Tungsten Nano-Tips Coated with Thin Layer of the EpoxyResin
Abstract
This paper reports results of analysis of field ion emission mechanism from tungstenepoxy composite emitters that are compared to tungsten nanofield emitters. In this context, the mechanism of emission from this type of emitters is described based on a theory of induced conductive channels. The tungsten emitters were prepared using the electrochemical polishing technique and coated with a layer of the epoxy resin. Field ion microscope (FIM) analyses are reported including the study of the emissionion density distributions from both the uncoated and coated emitters. Two forms of emission patterns have been observed in the ion emission microscopy technique describing the differences in the emission mechanism of both types of emitters. The observed results show: (a) the expected crystalline surface atomic distribution images of the field ion microscopy in the case of uncoated tungsten tips, and (b) randomly distributed emission spots that describe the locations of the induced conductive channels inside the resin coating layer.
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Article Not peer-reviewed version Field Ion Microscopy of Tungsten NanoTips Coated with Thin Layer of the Epoxy Resin Dinara Sobola * , Ammar Alsoud , Alexandr Knápek , Marwan Mousa , Richard Schubert , Pavla Ko č ková , Pavel Škarvada * Posted Date: 30 July 2024 doi: 10.20944/preprints202407.2357.v1 Keywords: Field ion emission; tungsten atomic distribution; epoxy molecular distribution; composite field emitter; composite electron sources Preprints.org is a free multidiscipline platform providing preprint service that is dedicated to making early versions of research outputs permanently available and citable. Preprints posted at Preprints.org appear in Web of Science, Crossref, Google Scholar, Scilit, Europe PMC. Copyright: This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Article FieldIonMicroscopyofTungstenNano‐TipsCoated withThinLayeroftheEpoxyResin DinaraSobola1,AmmarA.AlSoud2,AlexandrKnápek3,MarwanS.Mousa4,RichardSchubert 2,PavlaKočková2,PavelŠkarvada2,* 1InstituteofPhysicsofMaterials,CzechAcademyofSciences,Žižkova22,61662Brno,theCzechRepublic 2DepartmentofPhysicsFacultyofElectricalEngineeringandCommunicationBrnoUniversityof Technology61600BrnoCzechRepublic 3InstituteofScientificInstrumentsofCzechAcademyofSciencesKralovopolska14761264BrnoCzech Repubic. 4DepartmentofRenewableEnergyEngineering,JadaraUniversity,Irbid21110,Jordan. *Correspondence:[email protected];[email protected] Abstract:Thispaperreportsresultsofanalysisoffieldionemissionmechanismfromtungsten‐epoxy compositeemittersthatarecomparedtotungstennano‐fieldemitters.Inthiscontext,themechanismof emissionfromthistypeofemittersisdescribedbasedonatheoryofinducedconductivechannels.Thetungsten emitterswerepreparedusingtheelectrochemicalpolishingtechniqueandcoatedwithalayeroftheepoxy resin.Fieldionmicroscope(FIM)analysesarereportedincludingthestudyoftheemission‐iondensity distributionsfromboththeuncoatedandcoatedemitters.Twoformsofemissionpatternshavebeenobserved intheionemissionmicroscopytechniquedescribingthedifferencesintheemissionmechanismofbothtypes ofemitters.Theobservedresultsshow:(a)theexpectedcrystallinesurfaceatomicdistributionimagesofthe fieldionmicroscopyinthecaseofuncoatedtungstentips,and(b)randomlydistributedemissionspotsthat describethelocationsoftheinducedconductivechannelsinsidetheresincoatinglayer. Keywords:fieldionemission;tungstenatomicdistribution;epoxymoleculardistribution; compositefieldemitter;compositeelectronsources 1.Introduction Theterm‘fieldemission’candescribebothelectronandionemissionmechanisms.Basedon Fermi‐Diracstatis‐ tics,thephysicsbehindfieldemissiontheorywasintroducedasoneofthe significantapplicationsofquantum‐mechanicaltunnelingandfree‐electrontheoriesofcondensed matterinthe1920sand1930s[1–3].Coldfieldelectronemissionisthetransitionofelectronsthrough areducedpotentialenergybarrierfromthesurfaceofmicro/nanopointedemitter(tip)intovacuum. AccordingtoFowler‐Nordheimtheory,whentwoelectrodes(usuallyseparatedbyasmalldistance notmorethan10mm)withoneofthemisamicro/nanopointedemitter,andafterapplyinganintense electricfield(usuallyintherangeof3V/nm),electronscanquantum‐tunnelthroughanexact triangularpotentialenergybarrierfromenergylevelsclosetotheFermilevelofthematerialused[4– 9]. Inthecaseoffieldionemission(FIM),thesystemisusuallyfilledbyagasatlowpressure(such asHeorNe).Thenanotipissettobetheanodeallowingtheusedgasatomstobeionizedwhen locatedneartheapexsurface.Electronsfromtheusedgasatomscantunnelthroughthereduced potentialenergybarrierprovidingpositivelychargedions(likeNe+).Theseionsarethenaccelerated withintheappliedextractionelectricfieldto‐wardsthecathodewhichisanimagingscreen(usually a fluorescentscreen).TheobservedphotonsformwhatisknownastheFIMpattern,which describestheionsemissiondistribution(amagnifiedimageofthesurfaceatomicdistribution) asbeingemittedfromthesurfaceofthetip[10–14].Fieldionemittersareparticularlyattractive assourcesofionbeams.Duetotheirsuitableemissionpropertiesandsimpleoperatingprinciple, Disclaimer/Publisher’s Note: The statements, opinions, and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions, or products referred to in the content. Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1 © 2024 by the author(s). Distributed under a Creative Commons CC BY license.
2 thistypeofemittershasbeenusedinseveralapplications,suchasscanningionmicroscopy [15,16]. Theresultsasobtainedforthefieldelectronemissionmicroscopy(FEM)experimentsfrom compositeemitters(withmetal‐insulator‐vacuuminterface)reportedexoticandinteresting behavior,suchasobtainingaswitch‐oncurrent,wherethemeasurementoftheemittedcurrent isexceptionallyfoundathighvalues(theemissionprocesssuddenlystartsattherangeoffew micro‐amps)andtherelatedcurrent‐voltagecharacteristicshaslowerthresholdvoltages. AnotherbehaviorhasbeenreportedintheobtainedemissionpatternintheFEM,wherethe emit‐ tedcurrentdensitydistributionshowsmorefocusedandbrighterpatternthanthecaseof theuncoatedemitters.Inadditiontothat,differentbehaviorinthecurrent‐voltage characteristicshasbeenreportedalongwithlowerthresh‐ oldvoltagewhenoperatingthe experimentaftertheoccurrenceoftheswitch‐onphenomenon[17–26].TheFIMresultsfrom metal‐insulatorcompositeemittershavebeenpreviouslyreportedfromdifferenttypesof insulatorssuchaspolymers[27–31],theresultsshowrandomlydistributedlocationsofintense andbrightspotswithintheFIMpattern. InthisworkwediscusstheFIMresultsfromthetungsten‐epoxycompositeemitters.The resultspresentmultipleswitch‐onbehaviorandtheFIMpatternprovidesmoreevidenceforthe creationoftheinducedtunnelingconductivechannelsasdiscussedbefore. 2.MaterialsandMethods 2.1.Materials Tungstenis one ofthematerialsfrequentlyusedformanufacturingfieldemittertips[21,23], becauseofitssuitableproperties,suchasahighmeltingpointof3414 °C[32],stiffness ( strength ),highdensity,chemicalstability,alongwithhavingthelowestvaporpressureat 1650°C,inadditionto the simplepreparationofmicro/nano‐ tipemittersusingtheelectrolytic polishingtechniqueascathodeproductiontechnology[8,20]. Inthisexperiment,weusedhighpurity(99.99%)poly‐ crystallinetungstenwireswitha diameterof0.1 mm andaworkfunctionvalueof4.66eV[33],providedbyGoodfel‐ lowCambridge Ltd.(Huntingdon,UnitedKingdom).Be‐ foretheelectrochemicaletchingprocess,thetungsten sampleswereprepared1.0cminlength.Thesesampleswerethenetchedandfieldemissiontips withapproximately70nmofcurvatureradiuswereobtained.Thepreparedfieldemissiontipswere thenusedasuncoatedfieldionemittersandthebasematerialforthecompositeemitters. Asforthecoatinglayer,wehaveusedthesinglecom‐ ponentepoxyresinbrandedwith ‘Epoxylite478(E‐478)’,producedbyElantasEurope.TheE478epoxyresincon‐ sistsof Poly(BisphenolA‐co‐epichlorohydrin),Neopentylglycoldiglycidylether,polyglycol,and Trichloro(N,N‐dime‐thyloctylamine)boron.TheelectricalstructureoftheE478waspreviously reportedwithlocalworkfunctionvalueof 3.42eV,energygapof3.94eV,andelectronaffinity of 2.16eV[33].Thismakes the E478suitableforfieldionmicroscopyapplications. 2.2.Methodology 2.2.1.Electrochemical Etching Thetungstenwiresareplacedina0.4mmindiametercoppertubes.Thesamplesarethen attachedastheanodeofaspecialinstrument,wherethecathodeissettobeanickelwire. Thisinstrumentcanprovidefieldemissionnano‐tipswithapexradiusofapproximately20 nmusingthedrop‐offmethodoftheelectrochemicalpolishingtechnique.Theetchantusedisa 5Msolutionofsodiumhydroxide(NaOH),whereitisfoundbettertobeusedafter4‐7hours, untiltheNaOHparticlesarewelldissolvedandthesolutioniscooleddown.Tostartthe polishing process,approximately10mlofthesolutionisaddedintheinstrumentspecialplastic containerwherethetwoelectrodesareimmersedintheNaOHsolution.Theset‐upisthen connectedtoapowersupplyprovidingapolishingACvoltageof20V.Whenthetungstenwire beginstocorrode,thea ppliedAC voltage isgraduallyreduceduntilitreaches2 V.Thelatter Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1
3 pointisextremelyimportant,asthecut‐offtimeoftheetchingcircuitgreatlyaffectsthe sharpnessofthegeneratedtip. Thepreparedsampleswerethencleanedfromanyresid ualsofthehydroxidesolutiononthe surfaceofthetip.Thecleaningprocedureincludesimmersingthepolishedsamplesinalcohol followedbyadistilledwaterultrasonicbathfor20minutes. ThefollowedetchingprocedureinthisexperimentfulfillsthediameterrequirementforFIM experiments,since therequiredradiusoftheFIMtipshouldnotbelargerthan100nm, andthisprocedureprovidesFEtipswith radiiapproximatelyintherangeof20nmbeforethe coat ingprocess.Inthisexperiment,theradiusofcurvatureforthepreparedtipswas70 nm. 2.2.2.CoatingProcess To apply thecoatinglayersonthetipsurface,theNaOHsolutioncontainerisreplaced withanothercontaineroftheepoxyresin.Thecoatingprocessisbasedoncontrolledtip dippingandgenerallyinvolvestwomainsteps.Thefirststepistoimmersethecleanedtipin theepoxyresinslowlyandperpendicularlytotheresinsur‐face.Repeatingthisstepcreates thickercoatinglayers,aseachdipcreatesacoatinglayerof20nminthickness[17].Thesecond stepinvolvesheatingthecoatedtipsinavacuumfurnacefor5hoursat423K,Memmert UN55 (B u ¨ c h bac h, Germany).Thisstepisimportanttoexpelthesolventandtocuretheepoxy resinonthesurfaceof the coated tip[17,21]. Achievingadefinedimmersionandpreciseperpendicularityofthecoating(andetching) processisveryimportant.Forthisreason,theetchingdeviceisconnectedtoadigitalvisible‐ lightmicroscopetotracetheetching/coatingprocess.Thiscombinationisbetteradvisedtoobtain morecontrollableandmonitoredetching/coatingprocess. 2.2.3.FieldIonMicroscopy Thetestedemittershave beenusedasstandardFIMionsources.theseparationdistance betweenthesampleandtheFIMimagingscreenwassetto10mm.Thesampleshavebeen installedinsidealaserassistedwide‐angletomographicatomprobe(LaWaTAP)developedby Cameca(Gennevilliers,France).Inthisexperiment,Neon(Ne)gaswasusedastheimaginggas fortheFIMinvestigations.Inthiscase,thecathodewasaphosphorusscreen,andtheanodewas thesample.Thus,Neionsweregeneratednearthesamples’apexsurfaceundertheinfluenceof thedenseelectricfield,andthentobeprojectedtowardsthephosphorusscreen[10,15].The phosphorusscreenispreparedfromtransparentglasscoatedwithathinlayeroftin‐oxide, whichisthencoveredbyphosphoruslayertointeractwithincidentionsandrecordtheion emissionmicroscopepatterns. Thesystemtemperaturemustbekeptatverylowtemperaturesintherangeof30–90K,to reducesurfacediffusionofthesampleatomsandthusimprovethecontrolofthefield evaporationprocess.TheFIMexperimentshavebeenperformedinultra‐highvacuum conditionswherethebackgroundchamberpressureiskeptbelow10 − 9 Pa,and theNe imaging gaspressurewassetto10−5Pa[10,15]. 3.ResultsandDiscussion 3.1.FieldIonMicroscopy ThestructureofFIMpatternsfortheuncoatedtungstensamplesiswellknown[11].Forthe samplebeingdiscussedinthisarticle,thehighresolutionFIMimagefortheatomicstructureis obtainedat7.5kVaspresentedinFigure1,wherethesurfaceatomicdistributionshowsdifferent facetsofthepolycrystallinetungsteninthecenterofthefieldofview. Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1
4 Figure1. Thesurfaceatomicdistributionofpolycrystallinetungstennanotipasobtained fromfieldionemissionmicroscopyat7.5kV. Forthecoatedtungstensamples,thedetectedfieldelectronemission(FEM)behavioris characterizedbyaswitch‐onphenomenonandfocusedsinglebrightspot.Suchbehaviourhasbeen explainedbeforebyMousain1986by thecreationofcrystallizedchannelswhichallowthe electronspassthroughto/fromvacuumtothetungstensur‐face[17].ThedifferenceintheFEM behaviorbetweentheuncoatedandcoatedtungstensamplesispresentedinFigure2,andas observedbeforeelsewhere[34]. Figure2. Thefieldelectronemissionpatternof(a)coatedtungstentip,and(b)same uncoatedtip. Inthisstudy,theusedtipisconnectedtoahighvoltagepowersupply.Theappliedvoltage wasincreasedslowlyuntilthefirstionemissionprocessobservedat5kV,wheretheobserved FIMresultsaresplitintothreephases.Thefirstphasedescribesavoltageperiodfrom5 − 7kV and described inFigure3.Inthissitoffigures,theyellowhigh‐lightedregions(ofthebright spots)describetheimagingofthemoleculardistributionoftheresinlayer,whilethered Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1
5 highlightedregions(ofthedullspots)describetheatomicdistributionofthetungstensurfaceas obtainedthroughtheresinlayer. Figure3. Thesurfacemolecular(brightoryellowhighlighted)andatomic(dullorred highlighted)distributionsofcoatedpolycrystallinetungstennanotipasobtainedfrom fieldionemissionmicroscopyat(a)5.0kV,(B)5.5kV,(C)6.0kV,(D)6.6kV,(E)7.0kV, (F)7.2kV. Theappearanceofthebrightspots(yellowhighlightedregions)isrelatedtotheNe + when directlyionizedbytheorganicmoleculesattheresinsurface.Atthislevel,thebrighterthe spotsthehighergenerationdensityoftheemittedNe + canbeobtained,andthelargerinsize withmultipleconnectedcircularshapedregions(orspotswithtales)describetheimagingof moreatomswithinthesamemolecule. Theappearanceofthedullspots(redhighlightedregions)isrelatedtoindirectionization ofNe + .Thiscanbeobtainedatsurfaceregionswiththinresinlayer,wheretheelectronsofNe atomscantunnelthroughtheresinmoleculestothetungstensurfaceatoms,whichinturnhelps forlocatingandimagingofthesetungstenatomswithlowerdensityofemittedNe + . Sincemoleculesaresynthesizedbymorethananatom,theproductionoftheNe + willbe higherduetothein‐ creaseofthesuppliedionizationspots.Moreover,molecules havemore atomstobecapturedandimaged. Thisiswhythedifferenceinsizeandbrightnessbetween thetwobrightnesslevels(yellowandredregions)isrelatedtothedifferenceoftheimaged elements,whichprovideaproofforthesuggestedtheory.Aschematicdiagramofthisprocess isproposedinFigure4. ( a ) ( b ) ( c ) ( d ) ( e ) ( f ) Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1
6 Figure4. AschematicdiagramoftheionizationprocessofNegasonthesurfaceof coatedtungstensamples. Tosimplifythedetectionanddistinguishingmethodbetweentheresinsurfacemolecules andtungstensurfaceatomsweusethebrightnessleveloftheimagingspots.sincethemolecules arelargerinsizethanatoms,thecon‐ centrationofionizedNeatomswillbehigherwhen obtainedatmoleculesprovidingbrighterspots. Thesecondphaseoftheresultswereobtainedatthevoltagerange7 . 2 − 9 . 6kV.Atthis voltagerange,theFIMimagesshowonlytheatomicdistributionofthetungstensurfacethrough theresinlayer,whichisclearlyseenfromthedullspotsinFigure5.Thebrightspotsinthiscase aresmallerinsizethantheonesdescribedinFigure3,whichmeanstheydescribetungsten surfaceatomsbutwithmoreintenseionizationprocessfortheNegas. Figure5. Thesurfacemolecular(bright)andatomic(dark)distributionsof”coated” polycrystallinetungstennanotipasobtainedfromfieldionemissionmicroscopyat(a) 8.6kV,(B)9.0kV,(C)9.6kV. Thethirdandlastphaseoftheresultswereobtainedat thevoltagerange10 . 0 − 15 . 0kV.the FIMimages(Figure6) shownew active resinsurfaceregionstocontributeinthe Neionization process.Again,thebrightlargespotsarerelatedtoresinsurfacemolecules,whilethesmall brightanddullspotsarerelatedtotungstensurfaceatoms.Inadditiontowhat mentioned before, Figure6(d‐f)showblurredlargebrightspots,whicharebelievedtobeobtainedforinnerresin surfacemoleculesthatwereimagedbytunnelingionizationprocess,wheretheNe + wereionized bylosingtheirelectronswhenbeingtunneledtoinnersur‐facemolecule,wherethegradientin brightnessisrelatedtotheintensityofionizationofNegas. ( a ) ( b ) ( c ) Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1
7 Figure6. Thesurfacemolecularandatomicdistributionsofcoatedpolycrystalline tungstennanotipasobtainedfromfieldionemissionmicroscopyat(a)10.0kV,(B)11.6 kV,(C)12.8kV,(D)14.0kV,(E)14.6kV,(F)15.0kV.Theyellowhighlightedregions indicateinnerresinsurfacemoleculesimagedbytunnelingionizationcurrents. Atsomeregions,wheretheepoxylayerwasverythin, itwaspossibletoimagethetungsten surface atoms when theNe + arecreatedthroughtunnelingcurrents.Neelec tronswerecharging theresinmoleculeswhichinturnare discharged throughtheclosetungstenatom.Thisprocess helpstolocatetheseatomsinadditiontotheinnerresinsurfacemoleculesasseenfromthe blurredspotsinFigure6(d‐f). Achievingmorebrightandconcentratedemissionspots inthecaseofimagingtheresin surfaceisrelatedtothe highconcentrationoftheNegasionsinsmallareaswithintheresinsurface molecules,allowingtocreatelargedensity ofNe + atthesespotsduetoanintensethermal transitionoftheNegaselectronstotheresinsurface.Theseelec tronscaneasilyflyoverabove thereducedpotentialenergy barrier(PEB),whichisreducedbecauseoftwofactors;Thefirst isbecauseofalowerlocalworkfunctionvaluefortheepoxycoatinglayer(2.97eV),which reducestheheightofthePEBandsothevacuumlevel.Thesecondis whenapplyingan externalelectrostaticfieldinthespace betweenthetwoelectrodes,thePEBshapewillchange tobereducedimage‐roundedPEB,whichisknownastheSchottky‐NordheimSN‐PEB.The topofthisSN‐PEBcanbereducedbyincreasingtheintensityoftheelectrostaticfield,and whenapplyingextremelyintensefields,thetopoftheSN‐PEBwillbelowerthantheFermi leveloftheusedmaterial,allowingtheelectronstothermaltransferfromaboveofthe reducedSN‐PEB[4].ThiscanhelpforhigherdensityofNe+tobecreatedatsmallspots, andthenbeingemittedathigherdensitiesprovidingbrighterspotsontheimagingscreen. Thistheoryisvalidtoexplainthereasonwhythefieldionemissionprocessstartedatlower voltagesforthecaseofcoatedsamples(at5.0kV)incomparisonwithcase ofuncoated samples(at7.2kV).Inadditiontothis,thecoatedregionsofthecoatedsampleswereable tooperateathighervoltages(15.0kV)whencomparedtotheun‐coatedsamples(12.0kV). Thisprovidesmoreevidenceofthehigherlifetimeanddurabilityofthecoatedsamples.To provethisresult,atomprobetomographyanalysiswascarriedoutat15.0kVforthecoated samples,andtheresultsarediscussednextinsubsection. Anotherpossibleexplanationcanbediscussedwithinthiscontext,sincetheNeions willbeconcentratedwithinasmallvolumeabovethesurface,thismayallowforsecondary Ne+ionstobecreatedbythecollisionsbetweenthecreatedNe+ionsandtheNeions,which ofcoursecanincreasethedensityofthecreatedionsatthebrightregionsandso,the impactedionstotheimagingscreen. 3.2.AtomProbeTomographyAnalysis (a) (b) (c) (d) (e) (f) Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1
8 Thedistributionandcompositionofthe E‐478epoxyresinhavebeeninvestigatedusingthe atomprobetomography(APT)technique(Figure7).APTcanprovidequantitative informationandexactpositionsoftheresinmoleculesatgrainboundaries;theresultscan beobtainedwiththehighestavailablespatialresolution.TheAPTmeasurementswere performedonthesameinstrumentastheFIMmeasurements.Themeasurementswere carriedoutinvoltagemodeatatemperatureof75Kandpulsefractionsof5–15kVwith evaporationrates1–3%.DataevaluationwasperformedwithCameca’sTAP3Dsoftware. Figure7. Atomprobetomographyanalysisoftungsten‐epoxy(E‐478)compositeemitter. TheAPTresultshowsthatresinlayerwasnotevaporatedsincenoneoftheorganic compoundsweredetectedaspresentedinFigure7.However,thecoatedregionwas detectedbyeitherthewhiteregions(nothingwasdetected)orbyevaporatingthesilicon atomsfromresinlayer.Thisisevidenceofthelong‐lifetimeanddurabilityofthemetal‐ insulatorcompositefieldemitters. 5.Conclusions Withinthecontextofthisresearch,ithasbeenproventhatthecompositesources producesbrightandconcentratedemissionspots.Inbothemissiontechniques(FEMand FIM),thesespotsarecharacterizedbyhigheremissiondensitiesthanwhatcanbeachieved fromtheemissionprocessfromaregulartungstentips. Theemissionprocesshasbeendiscussedthroughthearticlebythecontextofthe creationofinducedconductivechannelsthroughthecoatinglayerbychargingtheresin moleculesthroughtheionizationofNegas,thendischargingtheinducedchargewhenthe electronstunnelthroughtheresinlayertotheconductiveregionoftungstensurface.The resultsasfoundfromFEMandFIMstudiesshowthatusingcompositemetal‐dielectricfield emittersisapromisingmethodologyinproducingelectron/ionbeamsources,thiswilladd severalbenefitstothetechnologyoftheelectron/ionbeaminstrumentssuchasscanning electron/ionmicroscopyandthefocusedelectron/ionbeamlithographydevices.Becauseof severaladvantagesofusingthistypeofelectron/ionbeamsources,suchasthefocusedand concentratedgeneratedbeams. Moreover,theAPTanalysisprovidedstrongevidenceofthedurabilityofthecoated samples,sincetheresinlayerwasnotevaporatedevenathighvoltages. Preprints.org (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2024 doi:10.20944/preprints202407.2357.v1