IEEE Press Series on Microelectronic Systems R. Jacob Baker, Series Editor Junctionless Field-Effect Transistors Design, Modeling, and Simulation Shubham Sahay and Mamidala Jagadesh Kumar JUNCTIONLESS FIELD-EFFECT TRANSISTORS IEEEPress 445HoesLane Piscataway,NJ08854 IEEEPressEditorialBoard EkramHossain,EditorinChief GiancarloFortino AndreasMolisch LindaShafer DavidAlanGrier SaeidNahavandi MohammadShahidehpour DonaldHeirman RayPerez SarahSpurgeon XiaoouLi JeffreyReed AhmetMuratTekalp JUNCTIONLESS FIELD-EFFECT TRANSISTORS Design, Modeling, and Simulation SHUBHAMSAHAY MAMIDALAJAGADESHKUMAR IEEE Press Series on Microelectronic Systems Copyright©2019byTheInstituteofElectricalandElectronicsEngineers,Inc.Allrightsreserved. PublishedbyJohnWiley&Sons,Inc.,Hoboken,NewJersey. PublishedsimultaneouslyinCanada. Nopartofthispublicationmaybereproduced,storedinaretrievalsystem,ortransmittedinanyformor byanymeans,electronic,mechanical,photocopying,recording,scanning,orotherwise,exceptas permittedunderSection107or108ofthe1976UnitedStatesCopyrightAct,withouteithertheprior writtenpermissionofthePublisher,orauthorizationthroughpaymentoftheappropriateper-copyfeeto theCopyrightClearanceCenter,Inc.,222RosewoodDrive,Danvers,MA01923,(978)750-8400,fax (978)750-4470,oronthewebatwww.copyright.com.RequeststothePublisherforpermissionshould beaddressedtothePermissionsDepartment,JohnWiley&Sons,Inc.,111RiverStreet,Hoboken,NJ 07030,(201)748-6011,fax(201)748-6008,oronlineathttp://www.wiley.com/go/permission. LimitofLiability/DisclaimerofWarranty:Whilethepublisherandauthorhaveusedtheirbesteffortsin preparingthisbook,theymakenorepresentationsorwarrantieswithrespecttotheaccuracyor completenessofthecontentsofthisbookandspecificallydisclaimanyimpliedwarrantiesof merchantabilityorfitnessforaparticularpurpose.Nowarrantymaybecreatedorextendedbysales representativesorwrittensalesmaterials.Theadviceandstrategiescontainedhereinmaynotbesuitable foryoursituation.Youshouldconsultwithaprofessionalwhereappropriate.Neitherthepublishernor authorshallbeliableforanylossofprofitoranyothercommercialdamages,includingbutnotlimitedto special,incidental,consequential,orotherdamages. Forgeneralinformationonourotherproductsandservicesorfortechnicalsupport,pleasecontactour CustomerCareDepartmentwithintheUnitedStatesat(800)762-2974,outsidetheUnitedStatesat (317)572-3993orfax(317)572-4002. Wileyalsopublishesitsbooksinavarietyofelectronicformats.Somecontentthatappearsinprintmay notbeavailableinelectronicformats.FormoreinformationaboutWileyproducts,visitourwebsiteat www.wiley.com. LibraryofCongressCataloging-in-PublicationDataisavailable. ISBN978-1-119-52353-6 PrintedintheUnitedStatesofAmerica. 10 9 8 7 6 5 4 3 2 1 DedicatedtoSaraswatiMata,theGoddessofLearning CONTENTS Preface xi 1 IntroductiontoField-EffectTransistors 1 1.1 TransistorAction, 2 1.2 Metal-Oxide-SemiconductorField-EffectTransistors, 4 1.3 MOSFETCircuits:TheNeedforComplementaryMOS, 9 1.4 TheNeedforCMOSScaling, 11 1.5 Moore’sLaw, 13 1.6 Koomey’sLaw, 13 1.7 ChallengesinScalingtheMOSFET, 13 1.8 Conclusion, 23 References, 23 2 EmergingFETArchitectures 27 2.1 TunnelFETs, 28 2.2 ImpactIonizationMOSFET, 34 2.3 BipolarI-MOS, 39 2.4 NegativeCapacitanceFETs, 41 2.5 Two-DimensionalFETs, 46 2.6 NanowireFETs, 49 2.7 NanotubeFETs, 51 2.8 Conclusion, 57 References, 58 vii viii CONTENTS 3 FundamentalsofJunctionlessField-EffectTransistors 67 3.1 DeviceStructure, 69 3.2 Operation, 70 3.3 DesignParameters, 80 3.4 ParametersthatAffectthePerformance, 82 3.5 BeyondSiliconJLFETS:OtherMaterials, 100 3.6 Challenges, 103 3.7 Conclusion, 110 References, 111 4 DeviceArchitecturestoMitigateChallengesinJunctionless Field-EffectTransistors 125 4.1 JunctionlessAccumulation-ModeField-EffectTransistors, 126 4.2 RealizingEfficientVolumeDepletion, 129 4.3 SOIJLFETwithaHigh-𝜅 Box, 131 4.4 BulkPlanarJLFET, 137 4.5 JLFETwithaNonuniformDoping, 140 4.6 JLFETwithaStepDopingProfile, 144 4.7 MultigateJLFET, 149 4.8 JLFETwithaHigh-𝜅 Spacer, 153 4.9 JLFETwithaDualMaterialGate, 157 4.10 Conclusion, 162 References, 162 5 Gate-InducedDrainLeakageinJunctionlessField-Effect Transistors 173 5.1 HoleAccumulation, 174 5.2 ParasiticBJTAction, 176 5.3 ImpactofBTBT-InducedParasiticBJTActiononScaling, 177 5.4 ImpactofSiliconFilmThicknessonGIDL, 179 5.5 ImpactofDopingonGIDL, 187 5.6 ImpactofSpacerDesignonGIDL, 189 5.7 NatureofGIDLinDifferentNWFETConfigurations, 190 5.8 DeviceArchitecturestoMitigateGIDL, 199 5.9 Conclusion, 248 References, 249 6 ImpactIonizationinJunctionlessField-EffectTransistors 255 6.1 ImpactIonization, 256 6.2 FloatingBodyEffectsinSilicon-on-InsulatorMOSFETs, 256 6.3 NatureofImpactIonizationinJLFETs, 260