LTPS工艺流程与技术

ShanghaiTianmaMicroelectronicsCo.,LtdLTPS工艺流程与技术AMOLEDZhaoBenGangSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.2a-Si<PS,andprocessKeyprocessofLTPSLTPSprocessflow目录SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.3LTPS:LowTemperaturePoly-Silicona-Si<PS,andprocessSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.4SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.5a-SiTFT<PSTFTSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.6SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.7SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.8LTPS&OLEDSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.9SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.10SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.11SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.12+dopingSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.13KeyprocessofLTPSSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.14CVD技术SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.15SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.16去氢工艺去氢工艺:高温烘烤;快速热退火;高温腔体或低能量激光去氢FTIR检测氢含量SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.17缓冲层作用:1.防止玻璃中的金属离子(铝,钡,钠等)在热工艺中扩散到LTPS的有源区,通过缓冲层厚度或沉积条件可以改善多晶硅背面的质量;2.有利于降低热传导,减缓被激光加热的硅冷却速率,利于硅的结晶SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.18SiO2,SiO2/SiNxSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.19四乙氧基硅烷SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.20highcostSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.21TEOSoxide具有低针孔密度，低氢氧含量，良好的台阶覆盖性。SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.22SiNx:1.具有高的击穿电压特性2.具备自氢化修补功能3.与多晶硅的界面存在过多的缺陷和陷阱，易产生载流子捕获缺陷和阈值电压漂移，可通过SiO2/SiNx克服绝缘层选择广泛应用于非晶硅栅绝缘层SiO2:1.台阶覆盖性2.与多晶硅界面匹配,应力匹配SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.23一般采用SiNx，SiO2,而SiO2/SiNx结构可以得到良好的电学特性，和氢化效果SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.24SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.25结晶技术SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.26ELA(ExcimerLaserAnnel)Sony公司提出，现在大部分多晶硅TFT公司采用linebeam工艺。LineBeamScanmode现在技术：XeFSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.27晶化效果a-SiP-SiSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.28PartiallymeltingregimeNear-completemeltingregimeMechanismofELACompletemeltingregimeSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.29MIC&MILC(MetalInducedLateralCrystallization)SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.30SPC（solidphasecrystallization）SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.31SPCSPCELA晶粒：200-300nmSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.32ComparisonofdifferentbackplaneSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.33离子注入技术V族元素(P,As,Sb)III族元素(B,Al,Ga)提供电子,形成N型半导体提供空穴,形成P型半导体半导体掺杂:PH3/H2,B2H6/H2SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.34离子注入机离子束呈细线状或点状,难以得到大的电流束,采取扫描方式注入,产能低;通过质量分析装置控制注入剂量,均匀度2%离子云注入机离子束线状,电流束较长,产能较高,成本低;通过法拉第杯控制注入剂量,均匀度5%SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.35LDD方块电阻小于10K欧姆/□方块电阻40K---100K欧姆/□SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.36LDD作用：抑制“热载流子效应”以较低的注入量在源极/漏极端与沟道之间掺杂,形成一浓度缓冲区,等效串联了一个大电阻,水平方向电场减少并降低了电场加速引起的碰撞电离产生的热载流子几率注入剂量过少则造成串联电阻过高,使迁移率下降;注入剂量过多则会失去降低漏极端边缘电场强度的功能.LDDSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.37SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.38•Repairbrokenbondsdamagediniondoping•IncreaseconductanceofdopingareaSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.39氢化处理的目的多晶硅晶粒间存在粒界态，多晶硅与氧化层间存在界面态，影响晶体管电性。氢化处理以氢原子填补多晶硅原子的未結合鍵或未飽和鍵，粒界态，氧化层缺陷，以及界面态，来减少不稳态数目，提升电特性：迁移率，阈值电压均匀性等。氢化处理方法1.等离子体氢化法：利用含氢的等离子体直接对多晶体和氧化层做处理2.固态扩散法：SiNx薄膜作为氢化来源，特定温度烘烤使氢原子扩散进入多晶体和氧化层氢化工艺SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.40SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.41SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.42LTPS的主要设备TEOSCVD激光晶化设备离子注入机快速热退火设备ICP-干刻设备HF清洗机PVD光刻机湿刻设备干刻设备CVD共用产线设备LTPS设备SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.43OLED蒸镀封装离子注入机AOI快速热退火设备激光晶化设备磨边清洗机SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.44SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.45FFS(Fringe-FieldSwitching)&IPS(In-PlaneSwitching)2020年3月46LTPS-TNLTPS-OLEDLTPS-IPSSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.47GateActiveSDPassivationITOPixelPoly（多晶硅刻蚀）CHD（沟道掺杂）M1（gate层）ND（n+掺杂）PD（p+掺杂）M2（SD层）PV（passivation）Via1（过孔1）RE（反射电极）PDL（像素定义层）Spacera-Si工艺Via2（平坦化层）Poly（多晶硅刻蚀）CHD（沟道掺杂）M1（gate层）ND（n+掺杂）PD（p+掺杂）M2（SD层）PV2（passivation）Via1（过孔1）ITO1Via2（平坦化层）ITO2LTPS-IPSLTPS-OLEDSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.48玻璃基板Glass玻璃投入清洗LTPSprocessflow预处理SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.49RTASystemOverviewModel：YHR-100HTCSTPort（3个）CSTRobot（1个）Chamber（2个）Coolingstage（4层）SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.50沉积缓冲层\有源层GlassPECVD缓冲层+有源层有源层缓冲层去氢防止氢爆工艺材料工艺条件Remark缓冲层PECVDSiNx/SiO2有源层PECVDa-Si去氢PECVDheatchamber清洗SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.51多晶硅晶化Glass晶化多晶硅测量XRD,RAMAN,SEM,AFM,MIC,UVSLOPESpinclean工艺材料工艺条件RemarkSpincleanO3water、BHF、CO2water、H2waterELAXeF(351nm)SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.52P-Si刻蚀(mask1)Glass光刻DriverareaPixelareaP-channelN-channel干刻P-Si去胶工艺材料工艺条件RemarkP-Si刻蚀p-Si450-500ÅSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.53P-Si刻蚀(mask1)Taper49SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.54PR沟道掺杂(mask2)B+P-channelN-channelChanneldoping光刻补偿vth工艺材料工艺条件Channeldoping1.B+掺杂n沟道2.根据Vth结果，调整掺杂类型与区域GlassDriverareaPixelareaP-channelN-channel去胶SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.55沟道掺杂SHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.56PRN+掺杂(mask3)GlassP-channelN-channelPHX+工艺材料工艺条件remarkN+dopingPHx+IonimplantingDose：1×1014-5×1014(ion/cm2)薄层电阻：103-104Ω/□PHOTOPRpeelingN+doping第3次光刻灰化去胶DriverareaPixelareaSHANGHAITIANMAMICRO-ELECTRONICSCO.,LTD.57N+掺杂(mask3)SH