1、TFT-LCD技术经典讲义Outline TFT-LCD Introduction a-Si TFT Technology L-T Poly Si TFT Technology SummaryTFT-LCD Introduction Classification TFT-LCD Scheme Basic Operation Principle Pixel Arrangement&ResolutionFlat Panel Display ClassificationFPDsPDPsLEDsLCDsPassiveActiveMIMTFTa-Si:TFTLTPS TFTHTPS TFTTN、STN.
2、etc.LCOS TFT-LCD IntroductionTFT Classification TFT-LCD Introduction a-Si TFT Amorphous Silicon TFT LTPS TFT Low Temperature Poly-Silicon TFT HTPS TFT High Temperature Poly-Silicon TFT a-Si TFT LTPS TFT HTPS TFTFabricated on On GlassFabricated Array&DriverLarge Size(10.4)Mediam Size(210.4)Small Size
3、(VnVs=VsCgsCstClcnCommonVnVVdVsstCVlclcCC lclcCC&)(Va-Si TFT Technology Scan Line Delay2)1(1NCRNCRiN)exp()(0NNtVVVVpixelppgsCVCV/1For 1st data line：pixelppgsNCVCV/4.0For N-th data line：Suppose Vs-Vs=0.4Vp-p11%60)(VVNa-Si TFT Technology High aperture ratio design BCB passivation layer process方法：用BCB代
4、替傳統之SiOx 或SiNx當做護 層材料優點：降低ITO與MII（data line)間的寄生電 容、增加開口率a-Si TFT Technology High aperture ratio designa-Si TFT Technology High aperture ratio design From IDMC 2000a-Si TFT Technology High aperture ratio design BCB gate metal planarization 方法：用BCB當作Gate line平坦化層 優點：增加開口率、降低Gate line阻值,解決 gate delay的
5、問題 a-Si TFT Technology High aperture ratio designa-Si TFT Technology BCB Planarization LayerBCB1m Al-Nd0246810010203040Diagonal(in)Resolution(1/mm)TaMoWAl-NdAl6k Al-Nd10k Al-NdUXGASXGAXGAa-Si TFT Technology ITO Define Cst(a)AR increase by ITO Cst(b)Conventional MI Cst a-Si TFT Technology Ring Shape
6、Cst Aperture ratioAperture ratioRing CstBlack Matrixa-Si TFT Technology Repair Lines&Ladder Scan Line TAB ChipArray AreaRepair LinesLaser RepairScan Line OpenInterlayer ShortShort after Repaira-Si TFT Technology Color Filter on TFTa-Si TFT Technology From SID 01Array on Color Filtera-Si TFT Technolo
7、gy From SID 01ESD Protection Common LineDiode Connect TFTBus Line Shorting BarTAB Pada-Si TFT Technology a-Si TFT Electrical Characteristics a-Si:H TFT Characteristics Threshold Voltage -Vth Mobility-Subthreshold Swing-SS Linearitya-Si:H Compositionc-Sia-Sia-Si:H0.1a-Si:H0.6a-Si TFT Technology a-Si:
8、H Basic Concept2.353.84a-Si TFT Technology TFT Operation&Typical Id-VgTypical a-Si TFT Id-Vg1.0E-131.0E-121.0E-111.0E-101.0E-091.0E-081.0E-071.0E-061.0E-05-10-505101520VgIda-Si Vd=0.1Va-Si Vd=10VVgs Vth Channel InducedVds=Vds-saturation =Vgs-Vth Saturation Region：222ddthgoxdVVVVCLWI2thgoxdVVCLWIa-Si
9、 TFT Technology Typical a-Si&p-Si TFT Id-VgTypical a-Si&p-Si TFT Id-Vg1.0E-141.0E-121.0E-101.0E-081.0E-061.0E-041.0E-02-10-505101520VgIdP-Si Vd=0.1VP-Si Vd=10Va-Si Vd=0.1Va-Si Vd=10Va-Si TFT Technology Vth-Constant Current MethodConstant Current Vth1.0E-131.0E-121.0E-111.0E-101.0E-091.0E-081.0E-07-1
10、0-505101520VgIdVth=Vfb+2f+Qd/Cin Vfb=ms-(Qss)/CinVfb：flat band voltage ms：work function Qss：surface states2f：strong inversion voltageQd：depletion region space chargeCin：gate insulator capacitanceConstant Current Define：Vd=0.1VVth=1.0V LWId10102a-Si TFT Technology Vth-Extrapolation MethodSaturation R
11、egion：Vds=10VVgs VthVds =Vds-saturation=Vgs-VthVth=1.0VExtrapolation Vth0.0E+005.0E-041.0E-031.5E-032.0E-03-10-505101520VgI d)()(thgoxdVVCLWI2thgoxdVVCLWIa-Si TFT Technology -MobilityMobility()00.10.20.30.40.505101520VgMobilitysvcmMAX242.0222ddthgoxdVVVVCLWIdoxgdmVCLWVIgdoxMAXmMAXVCWLg11)(MAXa-Si TF
12、T Technology SS-Subthreshold SwingMAXdVgILogSS)(1MINdILogVgSS)(1/SS-101234-10-505101520VgL og(Id)/V g (decade/V)33.0SS03.31SSMAXdVgILog)(a-Si TFT Technology LinearityId-Vd0.0E+004.0E-078.0E-071.2E-061.6E-062.0E-0605101520VdIdId-Vd0.0E+005.0E-081.0E-071.5E-072.0E-072.5E-0700.511.52VdIdId-Vd0.0E+005.0
13、E-081.0E-071.5E-072.0E-072.5E-0700.511.52VdIda-Si TFT Technology Gate Bias Stressa-Si TFT Technology Low Temperature Poly-Si TFT Technology LTPS TFT introduction a-Si Vs L-T Poly Si TFT Key Technology of LTPS TFTDifferent Crystalline SiliconSummary From SID 01TFT structureBottom gateTop gate時期時期Mid
14、90after Mid 90優點優點1.a-Si/insulator 連續沈積Larger grain size in channel side2.Easy to implant a-Si TFT process into LTPS TFT缺點缺點Smaller grain size in channel sideactive layer/insulator 非連續沈積Self-AlignmentBack side exposureGate Metal as maskNumber of mask89 masks59 masksTarget Marketsamll/medium small-la
15、rgeRemarkSony,Sanyo,Toshiba,MatsushitaSony,Sanyo,Toshiba,MatsushitaLTPS TFT Technology LTPS TFT structure 比較Top-Gate LTPS TFT ProcessLTPS TFT Technology From SID 01Leakage Current Suppression StructureLTPS TFT Technology From SID 01a-Si TFT Vs LTPS TFTa-Si TFTLTPS TFTDevice Structure bottom gate TFT
16、(BCE)Top-gate TFTNew Marketcompete against CRTAM-OLED,AM-PLED910 Masks process5 Masks(LG)Digital camera,Video camera,PDAs,car navigation,handheld PCs,Sub-notebook.Integrate circuit,Memory built-in pixel,AM-OLED,AM-PLEDMask requirementTarget MarketTechnology trend5-Mask process4-Mask process(Samsung,
17、Toshiba,ERSO)notebook PC,LCD monitor,camera,carnavigation.Large panel size,High resolution,Wide viewing angle,Fast response time,High transmittance,Reduce mask processLTPS TFT Technology Key Technology of LTPS TFTLTPS TFT Technology Buffer layer depositiona-Si depositionCrystallizationGate insulator
18、Ion dopingIon activation SPC(Solid Phase Crystallization)MIC/MILC(Metal Induced Lateral Crystallization)ELC(Excimer Laser Crystallization)CGS(Continuous Grain Silicon)CrystallizationLTPS TFT Technology Energy Density&Grain SizeLTPS TFT Technology From SID 99Grain Size&MobilityLTPS TFT Technology Fro
19、m SID 01Grain Size&Number of ShotsLTPS TFT Technology Sequential Lateral Solidification-SLSLTPS TFT Technology From SID 01ELA CrystallizationLTPS TFT Technology From SID 01Phase Modulated ELA(PMELA)LTPS TFT Technology From SID 01Summary Cost Down High Image Quality Enlarge Panel Size Compact Cost Do
20、wn Improve Yield Design New Material&Technology Process Reduce Mask Number Fully Dry Etching ProcessSummary High Image Quality High Resolution High TFT Driving Capability Low Scan Line Material Integrated Spacer CFonTFT or TFT on CF High Aperture Ratio Ring Cst Transparent Cst Top ITO ElectrodeSumma
21、ry High Image Quality Wild View Angle IPS MVA Film Compensate Color True Color Realize Improve LC Response Time New Material DevelopmentSummary Enlarge Panel Size Equipment Large Substrate Size New Facility Development Process Low Scan Line Material PlanarizationSummary Compact Thin Reduce Glass Sub
22、strate Thickness New Package Technology Back-Light Module Power Saving Design Other Light Source Light Weight Reduce Glass Substrate Thickness Plastic SubstrateSummary SummaryFuture Aims of LTPS-TFT panel High Image Quality Portable Enlarge Panel Size Concept of“System On Panel”High Image Quality Hi
23、gh Resolution Mobility Laser Process Doping Process Activation Process Hydrogenation Process Design Rule Photo Process Fully Dry Etching Process Wide View Angle LC OLEDSummary Portable Low Power Consumption SRAM&Circuit Design Uniformity Stability Back-Light Reflective LCD OLED Light Weight Substrat
24、e Back-Light Reflective LCD OLEDSummary Enlarge Panel Size Improve LTPS process Gate Material Mobility Planarization Uniformity StabilitySummary Concept of“System On Panel”Original Data：AMLCDs 95,An Overview of Active Matrix LCDs in business and technologySummary TOSHIBA Technology RoadmapYear200020
25、0020052005GenerationNowNext GenerationNext Next GenerationMobility()(cm2/Vs)100150300500Design Rule(m)431.51Clock Freq.(Hz)5M10M40M100MCircuits on GlassDriverShift RegisterDAC,Graphic I/F,Small Memory,LowPerformance CPU64Mbit Memory,32bit CPUSystem w/o TABFull Intergrated DisplaySheet ComputerDisplys LCDLCD/OLED?TOSHIBA Technology RoadmapSummary
