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OECDpublishing
CHIPS,NODESANDWAFERS
ATAXONOMYFOR
SEMICONDUCTORDATACOLLECTION
August2024
ECD
BETTERPOLlcIESFORBETTERLIVES
2lCHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION
©OECD2024
ThispaperwasapprovedanddeclassifiedbywrittenprocedurebytheDigitalPolicyCommittee(DPC)and
theCommitteeonIndustry,InnovationandEntrepreneurship(CIIE)on26July2024andpreparedforpublicationbytheOECDSecretariat.
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CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTIONl3
©OECD2024
Foreword
Thesemiconductorvaluechainissusceptibletodisruptionsthatposeaconsiderableriskformoderneconomies.Betterdataareessentialforpolicymakerstoidentifybottlenecks,monitorthebalancebetweendemandandsupplyofspecificsemiconductortypes,andmanagedisruptions.Thispapersetsoutacommontaxonomyforsemiconductortypesandproductionfacilities,tofacilitateharmoniseddatacollectionandsharing.Thetaxonomydistinguishessemiconductorproductsintofourbroadcategories–“logic”,“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.TheauthorsalsothankAnaísaGonçalvesandShaiSomekfortheirsupport.
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
CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTIONl5
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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
6lCHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION
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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–“logic”,“memory”,“analog”and“others”—andsub-categoriesbasedontheirprevalence,specificfunctionsandend-uses.Semiconductorproductionfacilitiesareclassifiedaccordingtothetechnologyusedandabilitytoproducedifferenttypesofsemiconductors(capability),aswellastheinstalledproductioncapacity.Italsoincludesinformationongeographic,demographicandotherrelevantplant(andfirm)characteristics.
Thistaxonomywillbethebasisforasemiconductorproductiondatabase.Thetaxonomymaythereforeneedtoberevisedinthefuture,keepingupwithdevelopmentsinsemiconductortechnology.Futureextensionstothetaxonomycouldinclude,conditionalondataavailability,additionalinformationonsemiconductorfirms,onendusesforsemiconductors,oronsemiconductorsubstitutability.
CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTIONl7
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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
©OECD2024
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.
10|CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION
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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.
CHIPS,NODESANDWAFERS:ATAXONOMYFORSEMICONDUCTORDATACOLLECTION|11
©OECD2024
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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