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OECDpublishing

CHIPS,NODESANDWAFERS

ATAXONOMYFOR

SEMICONDUCTORDATACOLLECTION

August2024

ECD

BETTERPOLlcIESFORBETTERLIVES

2lCHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION

?OECD2024

ThispaperwasapprovedanddeclassifiedbywrittenprocedurebytheDigitalPolicyCommittee(DPC)and

theCommitteeonIndustry,InnovationandEntrepreneurship(CIIE)on26July2024andpreparedforpublicationbytheOECDSecretariat.

NotetoDelegations:

ThisdocumentisalsoavailableonO.N.E.Members&Partnersunderthereferencecode:

DSTI/DPC/CIIE(2024)1/FINAL

Thisdocument,aswellasanydataandmapincludedherein,arewithoutprejudicetothestatusoforsovereigntyoveranyterritory,tothedelimitationofinternationalfrontiersandboundariesandtothenameofanyterritory,cityorarea.

Coverimage:?HAKINMHAN/S

?OECD2024

Theuseofthiswork,whetherdigitalorprint,isgovernedbytheTermsandConditionstobefoundat:

/termsandconditions

CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTIONl3

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Foreword

Thesemiconductorvaluechainissusceptibletodisruptionsthatposeaconsiderableriskformoderneconomies.Betterdataareessentialforpolicymakerstoidentifybottlenecks,monitorthebalancebetweendemandandsupplyofspecificsemiconductortypes,andmanagedisruptions.Thispapersetsoutacommontaxonomyforsemiconductortypesandproductionfacilities,tofacilitateharmoniseddatacollectionandsharing.Thetaxonomydistinguishessemiconductorproductsintofourbroadcategories–“l(fā)ogic”,“memory”,“analog”and“others”–andsub-categoriesbasedontheirprevalenceandspecificfunctions.Semiconductorproductionfacilitiesareclassifiedaccordingtothetechnologyusedandabilitytoproducedifferenttypesofsemiconductors,theinstalledproductioncapacity,aswellasotherrelevantplant(andfirm)characteristics.Thistaxonomywillbethebasisforasemiconductorproductiondatabaseandwillberevisedinthefuture,keepingupwithdevelopmentsinsemiconductortechnology.

ThispaperwaswrittenbyChiraagShah,Charles-édouardVandePutandFilipeSilva,underthedirectionofAudreyPlonk,GuyLalanneandVerenaWeber.TheauthorsgratefullyacknowledgefeedbackprovidedbytheSemiconductorInformalExchangeNetworkparticipantsaswellasAngelaAttrey,GalliaDaor,GregoryLaRocca,DavidKanter,Jan-PeterKleinhans,TobiasProettel,LeaSamek,SaraRomaniegaSanchoandAndySellarsonthedrafttaxonomyandearlierversionsofthisdocument.TheauthorsalsothankAnaísaGon?alvesandShaiSomekfortheirsupport.

4lCHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION

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Tableofcontents

Foreword3

Executivesummary6

Introduction7

1Scopeforthetaxonomyandsemiconductorproductiondatabase8

Aprimeronthesemiconductorvaluechain8

Goalsandpolicyquestions10

Principlesforasemiconductorproductiondatabase12

2Semiconductormanufacturing:Process,technologiesandproducts14

Maintypesoftechnologies14

Typesofsemiconductors17

3Existingtaxonomiesforsemiconductors20

SEMI20

WorldSemiconductorTradeStatistics(WSTS)20

CompoundSemiconductorApplications(CSA)Catapult22

IEEETaxonomyofEmergingMemoryDevices22

Othertaxonomies23

4Proposedtaxonomyforsemiconductors25

Buildingtheevidencebase:ataxonomyforasemiconductorproductiondatabase25

Ataxonomyforsemiconductortypes30

5Futurework32

References33

AnnexA.HScodesrelevanttosemiconductors36

Endnotes37

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FIGURES

Figure1.Semiconductorproductionstages8

Figure2.Shareofsemiconductorandprimaryvalueaddeddemand,201810

Figure3.Transistortypes:PlanarvsFinFETsvs.GAAFETs16

Figure4.Memorytypesofsemiconductors19

Figure5.Catapultsemiconductortaxonomy22

Figure6.IEEE’smemorytaxonomy23

Figure7.OECD’sproposedsemiconductorproductiontaxonomy27

Figure8.Capabilityinchipsfabs27

Figure9.Aggregatedanddetailedtaxonomyforsemiconductortypes30

TABLES

Table1.SummaryofWSTS’categorisationandproductdefinitions21

Table2.Semiconductorproductiondatabasevariablesanddefinitions28

Table3.Attributesoftransistortypeandprocesstechnologies29

TableAA.1.HScodesrelevanttosemiconductorproducts36

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Executivesummary

Semiconductorspowermoderneconomiesandareintegraltoamyriadofadvancedindustrialproducts.Semiconductorsarepresentinsmartphones,computers,cars,homeappliances,medicalequipment,LEDlights,orlasers,justtonameafew.Theyencompassadiverserangeofcomplexcomponents,fromadvancedlogicsemiconductorsenablingadvancedcomputingandmemorysemiconductorsfordatastorage,tobasicsensorsusedintemperaturemeasurement.Semiconductormanufacturingcanbeextremelycomplex,forexamplerequiringadvancedlithographymachinestoprintonfeaturesmeasuredinnanometresandcleanroomswithstrictcontroloverairborneparticles.

Inspiteofitscriticalimportance,thesemiconductorvaluechainissusceptibletodisruptions.Thesemiconductorvaluechainishighlysegmentedintoproductionstagestakingplaceindifferentgeographies,butwitheachstageoftencharacterisedbyhighgeographicalconcentration.Thisposesaconsiderableriskformoderneconomies.

Enhancingtheresilienceofthesemiconductorvaluechain,requiresevidence-basedpolicymaking.Betterdataareessentialforpolicymakerstoidentifybottlenecks,monitorthebalancebetweendemandandsupplyofspecificsemiconductortypes,andmanagedisruptionsinvaluechains.

TheOECDSemiconductorInformalExchangeNetwork(hereaftertheNetwork),convenedinJune2023,bringstogetherseniorgovernmentofficialstofacilitatetransparencyandinformationexchangeonsemiconductorvaluechains.Informedbyitsexchangesandinviewofdifferentsemiconductortaxonomiesusedacrossdifferenteconomies,thispapersetsoutacommontaxonomyforsemiconductortypesandproductionfacilities(plants),tofacilitateharmoniseddatacollectionandsharing.

ThetaxonomywasdevelopedbytheNetworkanddistinguishessemiconductorproductsintofourbroadcategories–“l(fā)ogic”,“memory”,“analog”and“others”—andsub-categoriesbasedontheirprevalence,specificfunctionsandend-uses.Semiconductorproductionfacilitiesareclassifiedaccordingtothetechnologyusedandabilitytoproducedifferenttypesofsemiconductors(capability),aswellastheinstalledproductioncapacity.Italsoincludesinformationongeographic,demographicandotherrelevantplant(andfirm)characteristics.

Thistaxonomywillbethebasisforasemiconductorproductiondatabase.Thetaxonomymaythereforeneedtoberevisedinthefuture,keepingupwithdevelopmentsinsemiconductortechnology.Futureextensionstothetaxonomycouldinclude,conditionalondataavailability,additionalinformationonsemiconductorfirms,onendusesforsemiconductors,oronsemiconductorsubstitutability.

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Introduction

TheworkoftheOECDSemiconductorInformalExchangeNetwork(hereaftertheNetwork)1pointedtotheimportanceofdevelopingataxonomyfortypesofsemiconductorsandproductionfacilities(plants)toallowforharmoniseddatacollectionandsharing.AharmonisedapproachtodatacollectionsupportstheobjectivesoftheNetworktoincreasetheunderstandingaboutsemiconductorsandhelpmembersmovetowardsmoreresilientsemiconductorvaluechains.ThispaperprovidesthecommonsemiconductortaxonomydevelopedbyNetworkandlaysdownfutureworkbasedonsemiconductorproductiondata.

Thecomplexityanddistributednatureofthesemiconductorvaluechainisoneofthekeychallengestoimprovingtransparencyandunderstanding.Developingataxonomyforclassifyingsemiconductordatathatenablesdataintegrationandcoversallstagesoftheproductionprocessisbothimportantbutalsoachallengingandresource-intensiveendeavour.Therefore,theNetworkispursuingatwo-prongedapproachtotheworkonsemiconductordata:i)conductanalysesfocusedonsemiconductorfabrication/front-endmanufacturingstage;ii)mapthesemiconductorecosystem,includingkeyupstreamanddownstreamactivitiesinthesemiconductorvaluechain.

Thispaperprovidesataxonomyforfront-endmanufacturing,layingthebasisforanalyticalworkonfacilities,processesandproductsfromthisstage.Experiencefromtherecent2020-2022semiconductorshortagesandrelatedanalysissuggestthatthisstagecanbeanimportantbottleneckinthevaluechain(Haramboureetal.,2023[1]).Nevertheless,othersegmentsinthevaluechaincanalsopresentbottlenecks,notablywhenthesupplyofcertaininputsisfoundtobehighlyconcentrated.

Afterdescribingthescopeandobjectivesforthechipsandfabstaxonomyandthesemiconductorproductiondatabase(Section

1)

,thispaperprovidesanoverviewofthesemiconductorproductionprocess(Section

2)

,includingthekeyinputs,technologies,chiptypes,andtheend-usemarketstohelpinformthetaxonomy.Section

3

outlinesdifferentapproachestoclassifyingsemiconductorproductionfacilitiesandproducts.Section

4

presentstheNetwork'sproposedtaxonomyforclassifyingsemiconductorproducttypes(chips)2andplants(fabs),andtheelementsofasemiconductorproductiondatabasetosupporttheNetwork'sobjectivesdescribedpreviouslyinSection

1.

Informationonstatisticalclassificationsrelevanttothesemiconductorindustryisprovidedin

AnnexA.

8|CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION

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1

Scopeforthetaxonomyand

semiconductorproductiondatabase

Thissectionbrieflydefinesthesemiconductorvaluechain.Itthenexplainsthepurposeofthechipsandplantstaxonomyandtheprinciplesforasemiconductorproductiondatabase.

Aprimeronthesemiconductorvaluechain

ThesemiconductorvaluechainconsistsofthreecorestagesdescribedinFigure1:

?Design:Thisstageincludessettingtherequirementsofthechip,designingitsarchitecture,andvalidatingitsdesignonatestbench.

?Fabrication:Buildingonawaferofsemiconductormaterial(typicallysilicon,seeSection2forothermaterials),thisstageconsistsinprinting(or“etching”)theintegratedcircuitdesignedinthepreviousstageonthewafer.Occurringatawaferfabricationplant(“fabs”),fabricationreliesonmanycomplexadvancedmanufacturingprocessesusingmanufacturingequipmentandchemicals.

?Assembly,TestandPackaging(ATP):Thisstageinvolvesslicingthewafersintoindividualchips,packagingthechipsintoframesorresinshells,andtestingthem.

Figure1.Semiconductorproductionstages

Source:Haramboure,A.etal.(2023),“Vulnerabilitiesinthesemiconductorsupplychain”,OECDScience,TechnologyandIndustryWorkingPapers,No.2023/05,OECDPublishing,Paris,

/10.1787/6bed616f-en

.

CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION|9

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Semiconductorfirmshavedifferentbusinessmodels.IntegratedDeviceManufacturers(IDMs)integrateallthreecoreproductionstageswhileotherfirmsspecialiseinasinglestage,aspartofout-sourcingandspecialisationstrategies.Forexample,“contractfoundries”(alsoknownas“pure-playfoundries”)specialiseinthefabricationofchips(front-end)designedbyotherfirms.“fabless”firmsfocusonlyonchipdesign.Similarly,OutsourcedSemiconductorAssemblyandTest(OSAT)firmsfocusonlyonthethirdandlastproductionstage(back-end).3

Thecoresemiconductorvaluechainreliesoncriticalupstreaminputs,including:specialisedsoftware(Electronic-DesignAutomation,EDA),intellectualpropertynecessarytodesignprocessorarchitecture,rawmaterials(e.g.silicon,rareearthminerals,platinumgroupmetals,gallium,germanium),chemicalsandgases,andcapitalequipment(depositionandlithographytools,metrology,andinspectionequipment)–seeHaramboureetal.(2023[1]);KleinhansandBaisakova(2020[2])forfurtherdetails.

TheEmergingTechnologyObservatory’sSemiconductorSupplyChainExplorer(ETO,2022[3])providesaninteractiveoverviewoftheessentialinputsinvolvedateachstageofthechipmanufacturingprocess.4

Stepsinthefront-endmanufacturing/semiconductorfabricationprocess

Keystepsinthefabricationprocessforchipsincludethefollowing(Timings,2021[4]):

1.Deposition:Depositingthinfilmsofconducting,isolatingorsemiconductingmaterialsonasiliconwafer.

2.Photoresistcoating:Coveringthewaferwithalight-sensitivecoating.

3.Lithography:Aphotolithographytoolpasseslightthroughaphotomasktodrawpatternsintothesiliconwafers,creatingthetinycircuitsthatcomprisesemiconductors.

4.Etching:Removingthedegradedphotoresisttorevealtheintendedpattern,usingeithergases(dryetching)orchemicals(wetetching).

5.Doping:Introducingimpuritiesintothesemiconductorcrystaltodeliberatelychangeitsconductivity.Thiscanbeachievedbydiffusion(inducingthemovementofimpureatomsfromareasofhighconcentrationtolowconcentration)orionimplantation(bombardingthesiliconwaferwithpositiveornegativeionstocreatetransistors).

Advancedpackagingblursthelinebetweenfront-andback-endmanufacturing

Theintroductionofadvancedpackagingtechniques,suchasheterogeneousintegrationandsiliconstacking,allowsformultipleintegratedcircuits(IC)inthesamepackage,enhancingchipperformancebeyondtraditionalgeometricscaling.Thetrendforincreasingintegrationwithinasinglechippackage(asanalternativetomultiplechipsonacircuitboard)isalsodrivenbyproductcostengineering(Bailey,2024[5]).

Theadvancedpackagingmarketisdominatedbyfan-outwafer-levelpackagingwithabout60percentmarketshare(Burkacky,KimandYeom,2023[6]),butnewertechnologiesinclude2.5-Dor3-Dstacking,integratedfan-out(InFO),andsystem-on-chiptechnologies,enablingthestackingofchipsorwafersverticallywithaninterposerconnectingthestackedchips(Burkacky,KimandYeom,2023[6]).Thereareseveralcategoriesof2.5-Dand3-Dstacking,basedonthekindofinterposerused,anddifferentmanufacturersusedifferentinterposertechnologies(Patel,2022[7];Burkacky,KimandYeom,2023[6]).TSMCleadsthemarketwiththeirchip-on-wafer-on-substrate(CoWoS)technology,whichisthemostpopularpackagingtechnologyforadvancedlogicchips,includingthoseusedinartificialintelligence(AI)applications.

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Advancedpackagingisrelevanttofront-endmanufacturingbecausetheinterposermustbefabricated,whichcanbedonein-housebyfoundries(Patel,XieandWong,2023[8]),inadditiontoOSATfirms.

Recentdevelopmentsintechnologyalsoinclude‘3Dintegration’,whichconsistsinbondingdirectlythechipsatthefront-endstage(e.g.copper-to-copperbonding).3D-integrationalsorequiresaspecificdesignofthebondedchips.Developmentsinlow-temperaturebondingandultra-thindevicelayerstackingareexamplesofafast-movingtechnologicalfrontierfor3D-ICs.

End-usesforsemiconductors

Semiconductorsareacriticalinputintoproductioninawiderangeofindustries.Forexample,intelecommunicationequipmentormotorvehicles,thevalueofsemiconductorsembodiedisaboutasimportantasenergycosts(Figure2).

Figure2.Shareofsemiconductorandprimaryvalueaddeddemand,2018

Note:Thesemiconductorsshareofvalueaddedtofinalproductsineachindustryisshowninblue,withthereddotindicatingthevalueaddedofprimaryenergy(includescoal,oilandgas)inthatindustryforcomparisonpurposes.Thesampleisrestrictedtothe20leadingpurchaseeconomies.Forinstance,semiconductorsrepresent1.5%ofthevalueaddedinmotorvehicles,onlyslightlylessthanprimaryenergy(2%).

Source:Haramboure,A.etal.(2023),“Vulnerabilitiesinthesemiconductorsupplychain”,OECDScience,TechnologyandIndustryWorkingPapers,No.2023/05,OECDPublishing,Paris,

/10.1787/6bed616f-en

.

Generally,mostanalysisofsemiconductordemandfocusesonsixmainend-usemarkets:computing/dataprocessing,consumergoods,communications,automotive,industrialgoods,government/military.5Computersandotherconsumerelectronicsaccountformostofthedemandforallsemiconductors.Electricalequipment,followedbytheautomotivesector,othertransportequipment,industrialmachinery,aswellastelecommunicationsarekeychipsusingsectors.Theproductionofmedicaldevicesisalsoanimportantusingsector(OECD,2019[9]).

Goalsandpolicyquestions

Byfocusingonimprovingtransparencyandinformationsharingonfront-endmanufacturing,thetaxonomypresentedinthispaperprovidesthebasisforadatabaseunderpinninganalysestoaddressthefollowingkeyquestions.

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Wherearetheproductionfacilitiesforfront-endmanufacturinglocated?

Analysisunderthisworkstreamwoulddrawonfabdatatohelpshedlightinwhichcountriessemiconductorproductioncapacityislocated.Answerstothisquestionwouldcontributetounderstandtheextentofmarketconcentrationandthusidentifypotentialbottlenecks.Moreover,dataonthelocationoffront-endmanufacturingfacilitiescurrentlybeingplannedorunderwaycouldprovideinsightsonwhetherrecentpolicyefforts(e.g.policystrategiesandinstruments)arehelpingdiversifysemiconductorproductionandreducetherisksofbottlenecksinthefuture.

Howisthebalancebetweensemiconductordemandandsupplyexpectedtoevolve?

Thesedatacouldalsohelpidentifysegmentswhereinstalledcapacityisgrowingfasterthandemand,andthereforecreatingrisksofexcesscapacityandunnecessaryredundancies,basedontheavailabilityofdemanddata.Thisanalysiswouldhelppolicymakersunderstandinwhichtypesofchipsinvestmentsshouldbeencouraged,withaviewbuildingamoreresilientoverallvaluechain.

Buildingonfront-endmanufacturingcapacityinformationandsemiconductordemanddevelopmentsandforecasts,theanalysiscouldhelpmonitorindustrycyclesandanticipateshortagesandgluts.Furthermore,thetaxonomywillfacilitatedistinguishingbetweendifferentsemiconductorproducttypes(Section

4)

,withthelevelofproducttypegranularitydependingontheavailabilityofbothproductioncapacityanddemanddataatthesamelevelofgranularity.

Whatisthepotentialforsubstitution?

Itisimportanttounderstandifandwhereproductionissubstitutablebetweenfabsinordertobuildmoreresilientvaluechains.

Addressingthisquestionwouldhelpbetterunderstandthedegreeofflexibilityinfront-endchipmanufacturingtocopewithsupply-demandimbalancesforcertainchips,includingintheeventoflocaliseddisruptionsandothershocks.

Comprehendingsubstitutabilityiscriticalwhenplanningformanagingworst-casedisruptionscenarios.Therearetwoimportantdimensionstosubstitutability:

?Chipsubstitutabilityreferstowhetheronespecificchipinanend-productcanbesubstitutedbyanothertoperformthesamefunctionswithaminimallossinperformance.

?Fabsubstitutabilityreferstowhethertheproductionofonechipcanbeswitchedtoanotherplant,andifso,therangeofchipsthatcanbeproducedwiththesameavailablefabequipmentandfacilities(orwithminortweaks).

Chipssubstitutability

Substitutabilityacrosschips—i.e.whetheraspecificchipcanbereplacedbyadifferentchipforperformingthesamefunctionsinanend-useproduct—isdependentontheiruseindownstreamindustriesandproducts.Substitutingonechipforanotherisnotstraightforwardandoftenrequiresre-designingthesystem—eithertheprintedcircuitboard(PCB)and/orre-writingsoftware.Inaddition,trustinsuppliersandsecurityconcernsarekeyconsiderationsfordownstreamindustryusersthatmightalsolimittheabilitytosubstitutespecificchips(Sperling,2022[10]).

Substitutabilitymightbelesschallengingforsimplerchips,formaturechiptypesandforuseswheresoftwarehasevolvedataslowerpace,andfutureworkcouldconsiderwhethertherearereadilyavailablesubstituteswithincertaintypesofsimplerandmaturechiptypes.Partoftheanalysesonsubstitutability

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wouldalsoneedtotakeintoaccountthedependenceoncriticalsemiconductorsofcertainapplicationsandindustries.Moreover,chipperformance(andthatoftheend-useproduct)wouldneedtoconsiderefficiency,capacityandcapability,forexamplebuildingonwell-establishedstandardperformancetestsandbenchmarks.6However,adetailedanalysisbasedforexampleonmetricsonchemicalresistanceandoperatingtemperaturerangewouldbedeemedtootechnicalandoutsidethescopeofthisWorkstream.

Fabsubstitutability

Whereasunderstandingchipsubstitutabilitywouldprovideinsightsonalternativesourcesofchipsintheeventofavaluechaindisruption,thekeytomanagingdisruptionsissubstitutabilityacrossfabs,includinginformationonwherepotentialsubstitutefabsarelocated.

Whilepartoftheanalysesrequiredtounderstandingfabsubstitutabilityrelatetotechnologicalcapacity,economicconsiderationsalsoplayanimportantrole.Economicconsiderationsinclude,forexample,capitalinvestmentsrequired,leadtimetochangeproductionlinesandproductioncostsoftherelevantfabs.

Principlesforasemiconductorproductiondatabase

Thissectionpresentsasetofproposedprinciplesfordevelopingthesemiconductorsproductiondatabase.Theseprinciplesreflectaprioritisationthatwouldhelpattaintheobjectivesoutlinedabove.

?Trust.Thetaxonomy,anydatasharingactivitiesandresultingdatabasesdevelopedinthecontextoftheNetworkshouldbuildonco-operationandtrustamongstgovernmentsandstakeholdersinthesemiconductorindustrytoensurethatdataandrelatedanalysesmeetsharedgoals.Respectingconstraintsassociatedwithsharinggranularindustrydatawouldbeparticularlyimportanttobuildingtrustwithstakeholders.

?Availability.Thetaxonomyshouldreflectavailabledata.Areasforwhichdataarenotavailablearenotincluded.Areasforwhichdataavailabilityisverylimitedareidentifiedassuchand,asinanydatabase,theremaybenumerousmissingvalues.Dataanalysesareonlyposs

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