第八章COMSIC工艺流程

第七章COMSIC制造工艺流程主要内容1.典型的亚微米CMOSIC制造流程图；2.描述CMOS制造工艺14个步骤的主要目的；4.讨论每一步CMOS制造流程的关键工艺。CMOS工艺流程中的主要制造步骤Oxidation(Fieldoxide)SiliconsubstrateSilicondioxideoxygenPhotoresistDevelopoxidePhotoresistCoatingphotoresistMask-WaferAlignmentandExposureMaskUVlightExposedPhotoresistexposedphotoresistGSDActiveRegionstopnitrideSDGsiliconnitrideNitrideDepositionContactholesSDGContactEtchIonImplantationoxDGScanningionbeamSMetalDepositionandEtchdrainSDGMetalcontactsPolysiliconDepositionpolysiliconSilanegasDopantgasOxidation(Gateoxide)gateoxideoxygenPhotoresistStripoxideIonizedoxygengasOxideEtchphotoresistoxideIonizedCF4gasPolysiliconMaskandEtchoxideIonizedCCl4gas1.双井工艺2.浅槽隔离工艺3.多晶硅栅结构工艺4.轻掺杂漏(LDD)注入工艺5.侧墙的形成6.源/漏（S/D）注入工艺7.接触孔的形成8.局部互连工艺9.通孔1和金属塞1的形成10.金属1互连的形成11.通孔2和金属2的形成12.金属2互连的形成13.制作金属3、压点及合金14.参数测试PassivationlayerBondingpadmetalp+SiliconsubstrateLIoxideSTIn-wellp-wellILD-1ILD-2ILD-3ILD-4ILD-5M-1M-2M-3M-4Polygatep-Epitaxiallayerp+ILD-6LImetalViap+p+n+n+n+2314567891011121314CMOS制作步骤一、双井工艺n-wellFormation1）外延生长2）厚氧化生长保护外延层免受污染；阻止了在注入过程中对硅片的过渡损伤；作为氧化物屏蔽层，有助于控制注入过程中杂质的注入深度。3）第一层掩膜4）n井注入（高能）5）退火312PhotoImplantDiffusion4PolishEtch5ThinFilms~5um(Dia=200mm,~2mmthick)PhotoresistPhosphorusimplant312p+Siliconsubstratep-EpitaxiallayerOxide5n-well4p-wellFormation1）第二层掩膜2）P井注入(高能)3）退火ThinFilms312PhotoImplantDiffusionPolishEtchp+SiliconsubstrateBoronimplantPhotoresist1p-EpitaxiallayerOxide3n-well2p-well二、浅曹隔离工艺STI槽刻蚀1）隔离氧化层2）氮化物淀积3）第三层掩膜，浅曹隔离4）STI槽刻蚀（氮化硅的作用：坚固的掩膜材料，有助于在STI氧化物淀积过程中保护有源区；在CMP中充当抛光的阻挡材料。）ThinFilms12PhotoPolishEtchImplantDiffusion34+IonsSelectiveetchingopensisolationregionsintheepilayer.p+Siliconsubstratep-Epitaxiallayern-wellp-well3Photoresist2Nitride41OxideSTItrenchSTIOxideFill1）沟槽衬垫氧化硅2）沟槽CVD氧化物填充12DiffusionPolishEtchPhotoImplantThinFilmsp-wellTrenchfillbychemicalvapordeposition1Lineroxidep+Siliconsubstratep-Epitaxiallayern-well2NitrideTrenchCVDoxideOxideSTIFormation1）浅槽氧化物抛光（化学机械抛光）2）氮化物去除ThinFilms12DiffusionEtchPhotoImplantPolishp-well12Planarizationbychemical-mechanicalpolishingSTIoxideafterpolishLineroxidep+Siliconsubstratep-Epitaxiallayern-wellNitridestrip三、PolyGateStructureProcess晶体管中栅结构的制作是流程当中最关键的一步，因为它包含了最薄的栅氧化层的热生长以及多晶硅栅的形成，而后者是整个集成电路工艺中物理尺度最小的结构。1）栅氧化层的生长2）多晶硅淀积3）第四层掩膜，多晶硅栅4）多晶硅栅刻蚀ThinFilms12DiffusionEtchPhotoImplantPolish34p+SiliconsubstrateGateoxide12p-Epitaxiallayern-wellp-wellPolysilicondepositionPolygateetch43PhotoresistARC四、轻掺杂；漏注入工艺随着栅的宽度不断减小，栅下的沟道长度也不断减小。这就增加源漏间电荷穿通的可能性，并引起不希望的沟道漏电流。LDD工艺就是为了减少这些沟道漏电流的发生。n-LDDImplant1）第五层掩膜2）n-LDD注入（低能量，浅结）ThinFilms12DiffusionEtchPhotoImplantPolishp+Siliconsubstratep-Epitaxiallayern-wellp-welln-n-n-1PhotoresistmaskArsenicn-LDDimplant2p-LDDImplant1）第六层掩膜2）P-轻掺杂漏注入（低能量，浅结）12DiffusionEtchPhotoImplantPolishThinFilmsp+Siliconsubstratep-Epitaxiallayern-wellp-wellPhotoresistMask1p-p-Photoresistmask1n-n-2BFp-LDDimplant2p-n-五、侧墙的形成侧墙用来环绕多晶硅栅，防止更大剂量的源漏（S/D）注入过于接近沟道以致可能发生的源漏穿通。1）淀积二氧化硅2）二氧化硅反刻12DiffusionEtchPhotoImplantPolishThinFilms+Ionsp+Siliconsubstratep-Epitaxiallayern-wellp-wellp-p-1SpaceroxideSidewallspacer2Spaceretchbackbyanisotropicplasmaetcherp-n-n-n-六、源/漏注入工艺n+Source/DrainImplant1）第七层掩膜2）n+源/漏注入ThinFilms12DiffusionEtchPhotoImplantPolishp+Siliconsubstratep-Epitaxiallayern-wellp-welln+Arsenicn+S/Dimplant2Photoresistmask1n+n+p+Source/DrainImplant1)第八层掩膜2）P＋源漏注入（中等能量）3）退火12DiffusionEtchPhotoPolishThinFilmsImplant3Boronp+S/Dimplant2p+Siliconsubstratep-Epitaxiallayern-wellp-wellPhotoresistMask11Photoresistmaskn+p+p+n+n+p+七、接触（孔）的形成钛金属接触的主要步骤1）钛的淀积2）退火3）刻蚀金属钛ThinFilms12DiffusionEtchPhotoImplantPolish32Tisilicidecontactformation(anneal)Titaniumetch3Titaniumdepostion1n+p+n-wellp+n+p-welln+p+p-Epitaxiallayerp+Siliconsubstrate八、局部互连工艺LI氧化硅介质的形成1）氮化硅化学气相淀积2）掺杂氧化物的化学气相淀积3）氧化层抛光（CMP）4）第九层掩膜，局部互连刻蚀1NitrideCVDp-wellp-wellp-Epitaxiallayerp+SiliconsubstrateLIoxide2DopedoxideCVD4LIoxideetchOxidepolish3DiffusionEtchPhotoImplantPolish3421ThinFilmsLI金属的形成1)金属钛淀积（PVD工艺）2）氮化钛淀积3）钨淀积4）磨抛钨(化学机械工艺平坦化)ThinFilmsDiffusionPhotoImplant3214EtchPolishn-wellLItungstenpolishTungstendepositionTi/TiNdeposition234LIoxideTideposition1p-wellp-Epitaxiallayerp+Siliconsubstrate作为嵌入LI金属的介质的LI氧化硅LImetalLIoxide九、通孔1和钨塞1的形成通孔1形成1）第一层层间介质氧化物淀积2）氧化物磨抛3）第十层掩膜，第一层层间介质刻蚀DiffusionEtchPhotoImplantPolish321ThinFilmsOxidepolishILD-1oxideetch(Via-1formation)23LIoxideILD-1oxidedeposition1ILD-1p-welln-wellp-Epitaxiallayerp+Siliconsubstrate钨塞1的形成1）金属淀积钛阻挡层（PVD）2）淀积氮化钛（CVD）3）淀积钨（CVD）4）磨抛钨ThinFilmsDiffusionPhotoImplant3214EtchPolishTungstenpolish(Plug-1)TungstendepositionTi/TiNdeposition234LIoxideTidep.1ILD-1p-welln-wellp-Epitaxiallayerp+Siliconsubstrate多晶硅、钨LI和钨塞的SEM显微照片PolysiliconTungstenLITungstenplugMag.17,000X十、第一层金属互连的形成1）金属钛阻挡层淀积（PVD）2）淀积铝铜合金（PVD）3）淀积氮化钛（PVD）4）第十一层掩膜，金属刻蚀2341TiNdepositionAl+Cu(1%)depositionTiDepositionLIoxideILD-1Metal-1etchp-welln-wellp-Epitaxiallayerp+SiliconsubstratePhotoEtchDiffusionImplant4132PolishThinFilms第一套钨通孔上第一层金属的SEM显微照片MicrographcourtesyofIntegratedCircuitEngineeringTiNmetalcapMag.17,000XTungstenplugMetal1,Al4p+Siliconsubstratep-Epitaxiallayern-wellp-wellLIoxideILD-1OxidepolishILD-2gapfill132ILD