Bellingham, Washington USA LibraryofCongressCataloging-in-PublicationData Xiao,Hong. Introductiontosemiconductortechnology/HongXiao.–2nded. p.cm. Includesbibliographicalreferencesandindex. ISBN978-0-8194-9092-6 1.Semiconductors–Designandconstruction.2.Semiconductorindustry.I.Title. TK7871.85.X532012 621.38152–dc23 0 2012013231 Publishedby SPIE P.O.Box10 Bellingham,Washington98227-0010USA Phone:+1360.676.3290 Fax:+1360.647.1445 Email:[email protected] Web:http://spie.org Copyright c 2012SocietyofPhoto-OpticalInstrumentationEngineers(SPIE) (cid:13) Allrightsreserved.Nopartofthispublicationmaybereproducedordistributedin anyformorbyanymeanswithoutwrittenpermissionofthepublisher. The content of this book reflects the work and thought of the author(s). Every effort has been made to publish reliable and accurate information herein, but the publisherisnotresponsibleforthevalidityoftheinformationorforanyoutcomes resultingfromreliancethereon. PrintedintheUnitedStatesofAmerica. Firstprinting Thistextbookisdedicatedtomywife,LiuHuang,andmysons,JarryXiaoand ColinXiao. Contents PrefacetotheFirstEdition.............................................................................. xxi PrefacetotheSecondEdition.......................................................................xxiii ListofAcroynms.............................................................................................. xxv Chapter1 Introduction.................................................................................. 1 1.1 BriefHistoryofIntegratedCircuits........................................................... 2 1.1.1 Firsttransistor................................................................................... 2 1.1.2 Firstintegratedcircuit.................................................................... 3 1.1.3 Moore’slaw....................................................................................... 5 1.1.4 Featureandwafersize.................................................................... 5 1.1.5 Definitionoftheintegratedcircuittechnologynode........... 10 1.1.6 Moore’slaworthelawofmore.................................................. 11 1.2 BriefOverviewofIntegratedCircuits....................................................... 12 1.2.1 Manufacturingmaterials............................................................... 12 1.2.2 Processingequipment..................................................................... 12 1.2.3 Metrologytools................................................................................ 13 1.2.4 Wafermanufacturing...................................................................... 13 1.2.5 Circuitdesign.................................................................................... 14 1.2.6 Maskformation................................................................................ 16 1.2.7 Waferprocessing.............................................................................. 19 1.3 Summary............................................................................................................. 19 1.4 Bibliography...................................................................................................... 20 1.5 ReviewQuestions............................................................................................. 21 Chapter2 IntroductiontoIntegratedCircuitFabrication.......................... 23 2.1 Introduction........................................................................................................ 23 2.2 Yield..................................................................................................................... 25 2.2.1 Definitionofyield........................................................................... 25 2.2.2 Yieldandprofitmargin.................................................................. 26 2.2.3 Defectsandyield............................................................................. 27 2.3 CleanroomBasics............................................................................................ 28 2.3.1 Definitionofacleanroom............................................................. 29 vii viii Contents 2.3.2 Contaminationcontrolandyield................................................ 30 2.3.3 Basiccleanroomstructure............................................................. 32 2.3.4 Basiccleanroomgowningprocedures...................................... 33 2.3.5 Basiccleanroomprotocols........................................................... 35 2.4 BasicStructureofanIntegratedCircuitFabricationFacility............ 36 2.4.1 Waferprocessingarea.................................................................... 37 2.4.1.1 Wetbay............................................................................... 37 2.4.1.2 Diffusionbay.................................................................... 38 2.4.1.3 Photobay........................................................................... 40 2.4.1.4 Etchbay............................................................................. 40 2.4.1.5 Implantbay....................................................................... 42 2.4.1.6 Thin-filmbay.................................................................... 42 2.4.1.7 Chemicalmechanicalpolishingbay......................... 44 2.4.2 Equipmentarea................................................................................. 45 2.4.3 Facilityarea....................................................................................... 45 2.5 TestingandPackaging.................................................................................... 46 2.5.1 Dietesting.......................................................................................... 47 2.5.2 Chippackaging................................................................................. 47 2.5.3 Finaltest.............................................................................................. 52 2.5.4 3Dpackaging.................................................................................... 53 2.6 FutureTrends..................................................................................................... 53 2.7 Summary............................................................................................................. 55 2.8 Bibliography...................................................................................................... 56 2.9 ReviewQuestions............................................................................................. 56 Chapter3 SemiconductorBasics................................................................ 59 3.1 WhatIsaSemiconductor?............................................................................ 59 3.1.1 Bandgap.............................................................................................. 59 3.1.2 Crystalstructure............................................................................... 61 3.1.3 Dopingsemiconductor................................................................... 61 3.1.4 Dopantconcentrationandconductivity.................................... 63 3.1.5 Summaryofsemiconductors....................................................... 64 3.2 BasicDevices.................................................................................................... 64 3.2.1 Resistor................................................................................................ 64 3.2.2 Capacitor............................................................................................. 66 3.2.3 Diode.................................................................................................... 69 3.2.4 Bipolartransistor.............................................................................. 70 3.2.5 Metal-oxide-semiconductorfieldeffecttransistor................ 72 3.3 IntegratedCircuitChips................................................................................. 74 3.3.1 Memory............................................................................................... 75 3.3.1.1 Dynamicrandomaccessmemory............................. 75 3.3.1.2 Staticrandomaccessmemory.................................... 75 3.3.1.3 Erasable programmable read-only memory, electricerasableprogrammableread-onlymem- ory,andflash..................................................................... 76 Contents ix 3.3.2 Microprocessor................................................................................. 78 3.3.3 Application-specificintegratedcircuits.................................... 79 3.4 BasisIntegratedCircuitProcesses............................................................. 79 3.4.1 Conventionalbipolartransistorprocess................................... 80 3.4.2 p-Channel metal-oxide-semiconductor process (1960s technology)........................................................................................ 81 3.4.3 n-Channel metal-oxide-semiconductor process (1970s technology)........................................................................................ 82 3.5 ComplementaryMetal-OxideSemiconductor........................................ 82 3.5.1 Complementarymetal-oxide-semiconductorcircuit........... 85 3.5.2 Complementarymetal-oxide-semiconductorcircuitpro- cess(1980stechnology)................................................................ 87 3.5.3 Complementary metal-oxide-semiconductor process (1990stechnology).......................................................................... 89 3.6 TechnologyTrendsafter2000..................................................................... 89 3.7 Summary............................................................................................................. 90 3.8 Bibliography...................................................................................................... 92 3.9 ReviewQuestions............................................................................................. 93 Chapter4 WaferManufacturing,Epitaxy,andSubstrateEngineering..... 95 4.1 Introduction........................................................................................................ 95 4.2 WhySilicon?..................................................................................................... 96 4.3 CrystalStructuresandDefects.................................................................... 97 4.3.1 Crystalorientation........................................................................... 97 4.3.2 Crystaldefects.................................................................................. 99 4.4 SandtoWafer.................................................................................................... 100 4.4.1 Crudesilicon..................................................................................... 100 4.4.2 Siliconpurification.......................................................................... 101 4.4.3 Crystalpulling.................................................................................. 102 4.4.3.1 Czochralskimethod....................................................... 102 4.4.3.2 Floatingzonemethod.................................................... 104 4.4.4 Wafering.............................................................................................. 105 4.4.5 Waferfinishing................................................................................. 107 4.5 EpitaxialSiliconDeposition......................................................................... 108 4.5.1 Gasphaseepitaxy............................................................................ 110 4.5.2 Epitaxialgrowthprocess............................................................... 111 4.5.3 Epitaxyhardware............................................................................. 112 4.5.4 Epitaxyprocess................................................................................. 114 4.5.5 Futuretrendsofepitaxy................................................................. 115 4.5.6 Selectiveepitaxy.............................................................................. 116 4.6 SubstrateEngineering..................................................................................... 116 4.6.1 Silicon-on-insulatorwafer............................................................ 116 4.6.2 Hybridorientationtechnology.................................................... 118 4.6.3 Strainedsiliconwafer..................................................................... 119 x Contents 4.6.4 Strainedsilicon-on-insulatorwafer........................................... 119 4.6.5 Strainedsiliconinintegratedcircuitmanufacturing............ 120 4.7 Summary............................................................................................................. 120 4.8 Bibliography...................................................................................................... 122 4.9 ReviewQuestions............................................................................................. 122 Chapter5 ThermalProcesses......................................................................125 5.1 Introduction........................................................................................................ 125 5.2 ThermalProcessHardware........................................................................... 126 5.2.1 Introduction....................................................................................... 126 5.2.2 Controlsystem.................................................................................. 127 5.2.3 Gasdeliverysystem........................................................................ 128 5.2.4 Loadingsystem................................................................................. 128 5.2.5 Exhaustsystem................................................................................. 129 5.2.6 Processingtube................................................................................. 129 5.3 Oxidation............................................................................................................. 129 5.3.1 Applications....................................................................................... 131 5.3.2 Preoxidationcleaning..................................................................... 135 5.3.3 Oxidationrate.................................................................................... 137 5.3.4 Dryoxidation.................................................................................... 139 5.3.5 Wetoxidation.................................................................................... 142 5.3.6 High-pressureoxidation................................................................ 145 5.3.7 Oxidemeasurement........................................................................ 146 5.3.8 Recentoxidationtrends................................................................. 149 5.4 Diffusion............................................................................................................. 150 5.4.1 Depositionanddrive-in................................................................. 152 5.4.2 Dopingmeasurement...................................................................... 154 5.5 Annealing............................................................................................................ 156 5.5.1 Postimplantationannealing.......................................................... 156 5.5.2 Alloyannealing................................................................................ 157 5.5.3 Reflow.................................................................................................. 158 5.6 High-TemperatureChemicalVaporDeposition.................................... 159 5.6.1 Epitaxialsilicondeposition.......................................................... 159 5.6.2 Selectiveepitaxialgrowthprocesses......................................... 160 5.6.3 Polycrystallinesilicondeposition.............................................. 160 5.6.4 Siliconnitridedeposition.............................................................. 164 5.7 RapidThermalProcessing............................................................................ 167 5.7.1 Rapidthermalannealing................................................................ 168 5.7.2 Rapidthermaloxidation................................................................ 171 5.7.3 Rapidthermalchemicalvapordeposition............................... 173 5.8 RecentDevelopments..................................................................................... 174 5.9 Summary............................................................................................................. 176 5.10 Bibliography...................................................................................................... 177 5.11 ReviewQuestions............................................................................................. 177