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Power semiconductor device: BasicsIchiro OmuraKyushu Institute of TechnologyJapanIEEE EDSWebinar Dec. 2, 2015Since1909Ichiro Omura Kyushu Inst. Tech.
Outline Introduction– History– Power electronics circuit Power semiconductor devices––––Power MOSFET / Super-junction MOSFETIGBTThyristorsLateral devices Future possibility Related technologyIchiro Omura Kyushu Inst. Tech.
1965 - "Moore's Law"Silicon Engine to drive ICTManufacturing cost percomponentGordon E. MooreCMOSNumber of componentsper integrated circuitIntegrated circuit patent in 1959Robert NoyceTo digital cost free ICT for everybodyIchiro Omura Kyushu Inst. Tech.
AC power distribution systemtransm.web.fc2.comwww.cz-toshiba.comAC to ACConstant frequencyNo active control functionIchiro Omura Kyushu Inst. Tech.
100 years of power device development (High voltage)1940Rotary converter(AC-DC)Electric Machine1960Mercury arc rectifier(AC-DC)Electronics(Vacum utron doped FZ waferCarrier Injection EnhancementCarrier lifetime controlEdge termination technologySemiconductorTechnologyChip Parallel operationCosmic ray SEUThin wafer technologyAdvanced LSI Tech.(CMOS, DRAM)0.1mmPhotos:Nippon inst. tech, MuseumNikkeiTokyu MuseumJR KyushuNagahama Railway MuseumToshibaIGBT(AC-DC/DC-AC, MOS gate)10-100umIGBTInsulated GateBipolar TransistorIchiro Omura Kyushu Inst. Tech. 1-10um
PWM: Pulse Width ModulationModulation waveCarrier wavePWMModulated signal to PowerSemiconductor switch (ON/OFF)IGBTMotorACPDS: Power Drive System1. PWM signal control power semiconductors switch (ON / OFF)2. Motor current follows the modulation waveIchiro Omura Kyushu Inst. Tech.
Hybrid electric vehicle propulsion systemHalf-bridge boost 500VconverterInverter for motorInverter for generatorBattery 200VIGBTPower DiodeMotorTotal chip area for IGBTand power diode is morethan 40 cm2 of siliconwafer for Toyota Prius[*].Z. Shen and I. Omura. Proceeding of the IEEE, Vol.95 No. 4, 2007.(Figure)*A. Kawahashi et al., Proc. of ISPSD 2004, pp. 23-29,2004.Ichiro Omura Kyushu Inst. Tech.RCGeneratorSCRICEto WheelsRing gearCarrier/Planetary gearSun gear
Power Semiconductor DevicesIchiro Omura Kyushu Inst. Tech.
Power Semiconductor DevicesVertical deviceHighLTTGCT/GTOGTOGCTMOS-gateBipolar gateSystem PowerOpt- turn-onLTT1GWIGBTIGBT1kWPowerMOSFETPower MOSIGBT: Insulated Gate Bipolar TransistorGTO: Gate Turn-off ThyristorGCT: Gate Commutated Turn-off ThyristorLTT: Light Triggered Thyrisotor (optical fiber coupled)Low MOS gate devices cover wide-power range. Bipolar gate devices cover very high power applications( 10MW).Ichiro Omura Kyushu Inst. Tech.Photos:InfineonToshibaABBTMEIC
Types of power semiconductors(Switch)IGBTPower MOSFETN-sourceSourcePNP-wellMOS control UnipolarN-driftN-subN-sourceGateGatePP-baseN-MOS control BipolarN-N-basePP-emitterN EmitterCollectorDrainThyristors (GTO,GCT)GateP-baseIGBT: Insulated Gate Bipolar TransistorGTO: Gate Turn-off ThyristorGCT: Gate Commutated Turn-off t control BipolarPAnode1. MOS-gate (voltage) control or bipolar gate (current) control2. Unipolar conduction or bipolar conduction in high resistive layer(N-)Ichiro Omura Kyushu Inst. Tech.
Electric CurrentVoltageRemark: Vertical Device StructureCross section of active areaTop viewActiveareaEdge termination areaCellIchiro Omura Kyushu Inst. Tech.
Power MOSFETOpt- turn-onHighLTTGCT/GTOGTOGCTMOS-gateBipolar gateSystem PowerLTT1GWIGBTIGBT1kWPowerMOSFETPower MOSLowIchiro Omura Kyushu Inst. Tech.Photos:InfineonToshibaABBTMEIC
Power rentDrainDC to DC ConverterN-subCPU LoadHigh Side MOSFETDrainInductorImput VoltateCPU-chipSync. Rect. MOSFETOutput CapacitorConduction carrier Electron or holeSwitching control . MOS-gateSwitching Freq. . HighIchiro Omura Kyushu Inst. Tech.De-coupling Capacitor
Function of N-drift layern Function of N-drift layer:1. Voltage blocking (higher breakdown voltage)2. Current conduction (lower resistivity)Voltage tronEyEyLdriftChargeneutralityEdDrain(VB)Blocking state (Poisson eq.)dE yEdqN D ε ε dyLdriftIchiro Omura Kyushu Inst. Tech.EcondDrainConduction state (current eq.)J n qμ n N D EcondVcond qμ n N DLdriftμn: electron mobility
Drift layer doping, length and drift layer resistanceLdriftyEcritIchiro Omura Kyushu Inst. Tech.1VB Ecrit Ldrift2EcritqN D ε LdriftEcrit: critical E-field strengthDrift layer dopingDrift layer length2EcritND ε 2qVBLdriftRdriftX105 V/cm3.02.52.01.5ｐ1.04VB2 3μ nε Ecritｎ-Ecrit5.00.01012101310141015N-drift Donor Concentration (/cm3)2VB EcritVcondJ n qμ n N DLdriftDrift layer resistance[Ωcm2]Critical Electric Field for Silicon 10kV
Low Voltage MOSFET (Vertical)GateSourceFig from Lecture Slide byW. Saito, ToshibaN-sourceP-wellN-drift layer1000RonA 1001000Breakdown voltage (V)1. Cell size reduction for channel density2. Trench gate for channel density and JFET resistance removal3. Charge compensate (Vertical Field Plate) technology for driftresistance reduction.Ichiro Omura Kyushu Inst. Tech.
Super Junction MOSFET1000Fig from Lecture Slide byW. Saito, 1001000Breakdown voltage (V)P/N column drift layer Easy to deplete for high impurity concentration Low Ron High Breakdown VoltageCharge compensate (Super Junction) technologyfor drift resistance reduction.On-resistance RonA(mΩcm2)RonA (mΩcm2）Si-limit252015erghiH10mluconngpiod5VB 700V00Ichiro Omura Kyushu Inst. Tech.510152025P/N column pitch (μm)30
Column doping(ND) and Breakdown Voltage(VB)1. Horizontal field for P/N column depletiondE x2 EholqN D ε ε dxWcolumnExEholEySourceExVBWcolumnEy3. A half area of drift layer contributecurrent conductionJn 1qμ n N D Econd2WcolumnDrainVerticalfieldEvertVB Evert Ldrift2.Vertical field for voltage blockingbetween drain and sourceElectric field in SuperJunction structure high drift layer donor doping1. Horizontal electric field for depletion of PN junction in narrow columnsIchiro Omura Kyushu Inst. Tech.2. Vertical electric field for sustainblocking voltage across drift layer
Drift layer doping, length and drift layer resistance2 EholqN D ε WcolumnEhol VB Evert LdriftEvert Drift N-columndopingEcrit2Ldrif2 VB EcritEcrit2Ecrit22 EcritND ε qWcolumnDrift layer lengthEhol E EcritEcrit2EvertHorizontal fieldExEholEysourceVcond11J n qμ n N D Econd qμ n N D22LdriftDrift layer resistance[Ωcm2]Rdrift2VB Wcolomn 2μ nε EcritAssumption: N-column and P-columnaresameKyushuwidth Inst. Tech.IchiroOmuraVBWcolumnDrainEvertVB
IGBTInsulated Gate Bipolar TransistorOpt- turn-onHighLTTGCT/GTOGTOGCTMOS-gateBipolar gateSystem PowerLTT1GWIGBTIGBT1kWPowerMOSFETPower MOSLowIchiro Omura Kyushu Inst. Tech.Photos:InfineonToshibaABBTMEIC
IGBTShen, Omura, “Power Semiconductor Devices for Hybrid,Electric, and Fuel Cell Vehicles” Proc. Of the IEEE, Issue 4, 2007EmitterGateCollectorIcRated Current Density(A/cm2)500300 Carrier enhancement effect200Non latch-up IGBT1.2.3.4.VceProtectionThermal managementThin wafer PTNoise control100IPMTrench gateNPT-IGBT5019850.8VHigh Temp.Thin wafer NPT1990199520002005YearBipolar Transistor MOSFET (before IE-effect)High current capability 0.8V collector-emitter threshold voltage for conductionMedium switching speed (15kHz for motor drive, 100kHz for ICTcurrent supply and FPDIchirodriverOmura )Kyushu Inst. Tech.20102015
Operation mechanism of IGBTConduction modulation in N-baseIonized impurity (donor)E 0Unipolarpositive negativedε E q ( N D n) 0dxpn ni2φ p φnElectronE 0E 0ConductionmodulationHoledε E q ( N D p n) 0dxE 0pn ni2 eN D p, Collectorni p nPN-junction built-inpotentialConduction modulation1. Both hole and electron contribute to currentconduction2. High stored carrier density in N-base ( 1016cm-3)3. Built-in voltage with the stored carrierIchiro Omura Kyushu Inst. Tech.q(φ p φn )kTIGBTIcMOSFET0.8VVce
Punch-through IGBT (PT-IGBT)N-sourceP-baseEpitaxial layerwith carrierlifetime controlEmitterElectric field at Stored Carrierblocking state during on-stateGateN-baseN-bufferP-emitterHigh minority carrier(hole) injection efficiencyLow resistanceP-type SubstrateCollector1. Epi grown N-buffer (field stop) andshort / lightly doped N-base2. High minority (hole) carrierinjection from P-emitter3. Low-conduction loss and largeswitching loss4. Carrier lifetime control (high energyelectron irradiation etc.) requiredIchiro Omura Kyushu Inst. Tech.
Non-Punch-through IGBT (NPT-IGBT)N-sourceP-baseEmitterElectric Field at Stored Carrierblocking stateduring on-stateGateNeutrontransmutationdoped waferN-baseLow minority carrier(hole) injection efficiencyShallow P-emitterCollectorNeutron transmutation dopingM. Tanenbaum and A. D. Mills J. Electrochem. Soc., vol. 108, pp.171 1961J. Cornu and R. Sittig IEEE Trans. Electron Devices, vol. ED-22, pp.108 1975IAEA-TECDOC-1681, Neutron Transmutation Doping of Silicon at Research Reactors,2012Ichiro Omura Kyushu Inst. Tech.1. NTD wafer without N-buffer2. Low minority (hole) carrierinjection from P-emitter3. Higher-conduction loss andlower switching loss4. No carrier lifetime controlrequired
Thin wafer IGBT technologyEmitterN-sourceP-baseElectric field at Stored Carrierblocking state during on-stateGateNTD waferetc.N-baseN-bufferShallow P-emitterCollectorN-base lengthP-emitter holeinjectionCarrier lifetimein ortLongLongThin Wafer Technology-Reduction of turn-off tail current with short N-base-Reduction of conduction loss with short N-baseLow Hole Injection P-emitter with long carrier lifetime-Reduction of turn-off tail current with low hole injection-Better thermal coefficient without carrier lifetime controlIchiro Omura Kyushu Inst. Tech. FS-IGBT
Problem in High Voltage IGBT Device DesignGateN-sourceEmitterP-baseStored Carrier duringon-stateElectroncurrentHigh conduction resistancefor high voltage IGBTHole currentCarrier storageN-basePemitterN-bufferCollectorIchiro Omura Kyushu Inst. Tech.
Electron Injection Enhancement EffectGateEmitterN-sourceP-baseStored Carrierduring on-stateElectroncurrentHole currentPemitterN-bufferCarrier storageN-baseKitagawa et al. “A 4500 V injection enhanced insulated gate bipolartransistor (IEGT) operating in a mode similar to a thyristor,” IEDM’93,1993.Omura et al. “Carrier injection enhancement effect of high voltage MOSdevices-device physics and design concept,” ISPSD 97, pp. 217-220,1997.Omura, “High Voltage MOS Device Design: Injection Enhancement andNegative Gate Capacitance, (ETH thesis 2000), Series inMicroelectronics Vol. 150, Hartung-Gorre Verlag, 2005.CollectorTrench gate technology with special structure enhances majority carrier (electron)Ichiro OmuraKyushu Inst.injection in N-base Low conductionloss underhighTech.current density
Summary of IGBT Technology Trench Gate–Conduction loss reduction with electron injection enhancement–Channel resistance, JFET resistance reduction Low Injection P-emitter Long CarrierLifetime– Turn-off loss reduction with low hole storagein N-base– Better thermal coefficient without carrierlifetime control Thin Wafer Technology– Both conduction and turn-off loss reduction withwith short N-baseIchiro Omura Kyushu Inst. Tech.N-baseP-emitterGate
Conduction and Breakdown VoltageVoltage blockingGateE-fieldEmitter(flat carrier distribution is assumed)ElectronEyFloating PholenE-fieldpHoleElectroncurrent currentPemitterN-bufferp n nstoredCollectorN-base lengthStored CarrierdensityN-base conductionresistanceVBVB Ln base 2EcritEcritRN basePN-junction built-inpotentialVbuilt innstoredEyCharge neutralityN-baseConductionkT nstroed 2lnqniIGBT1 2 VB q ( μ n μ p ) nstored EcritIchiro Omura Kyushu Inst. Tech.IcMOSFET0.8VVce
DMOSFET.SJ-MOSFETIGBTGateEmitterFloating PN-baseDevice StructureHoleElectroncurrent currentPemitterN-bufferCollector2EcritND ε 2qVBDrift Layer Doping(Stored carrier density)Ldrif Drift Layer Length(N-base length)Drift Layer Resistance(N-base conductionresistance)PN-junctionbuilt-in potential600V class deviceRdrift2VBEcrit4VB2 3μ nε Ecritnstored2 EcritND ε qWcolumnLdrif Rdriftnone80-100 mΩcm22 VBEcrit2V W B colomn2μ nε Ecritnone 10 mΩcm2Assumption: N-column and Pcolumn are same width( 1016cm-3)Ln base RN base 1 2VBEcrit1 2 VBq( μ n μ p ) nstored EcritVbuilt in 2kT nstoredlnqni 1.5V at 200A/cm2(flat carrier stored carrierdistribution is assumedIchiroofOmuraKyushu Inst.Tech. 2007. IWPSD 2007, pp. 781 – 786, 2007Omura et. al, International Workshop on PhysicsSemiconductorDevices,
DMOSFET.SJ-MOSFETIGBTGateEmitterFloating PDevice StructureN-baseHoleElectroncurrent IDRON RdriftVDSIDRON RdriftVDSIcRN baseVbuilt inVceSwitchingcharge (turn-offcharge)Charge in main-junctioncapacitancePN-column depletionchargeStored carrier sweep outIchiroofOmuraKyushu Inst.Tech. 2007. IWPSD 2007, pp. 781 – 786, 2007Omura et. al, International Workshop on PhysicsSemiconductorDevices,
Types of Power SemiconductorsOpt- turn-onHighLTTGCT/GTOGTOGCTMOS-gateBipolar gateSystem PowerLTT1GWIGBTIGBT1kWPowerMOSFETPower MOSLowIchiro Omura Kyushu Inst. Tech.Photos:InfineonToshibaABBTMEIC
Light Triggered Thyristor(LTT)Photos: hodeAnodeImpurityconcentrationN-baseStored carrier concentrationunder current conduction1.4GW system by ToshibaForward ConductionblockingReverseblocking1.2.3.4.5.6.PNPN structureLight triggered turn-onCannot turn-off by gateOne wafer per one devicePressure contact packageHighest power per single semiconductorTrigger pulseIchiro Omura Kyushu Inst. Tech.
GCT: Gate Commutated Turn-off ThyristorGate drive current1.2.3.4.5.PNPN structureOne wafer per one device 100um cell sizePressure contact packageVery low stray inductanceintegrated gate driver forcouple of kA gate current6. Highest power per singlesemiconductor turn-off deviceABB GTO(GCT)ABB5.5kV, 5kA HPT IGCTIntegrated gate circuitABBIchiro Omura Kyushu Inst. Tech.
Lateral DevicesControl and Power Power ICMotor DriverCollectorEmitterOxideBOX 1kVSubstrateToshibaSourceAudio Speaker Driver 100VTrypath datasheetIchiro Omura Kyushu Inst. Tech.P n Gaten-driftDrainn
RESURF principle for breakdown voltage designBreakdown at verticalPN-junctionLow dose N-driftDrainGateN N N-driftPN PGNDElectricfieldFigure J. A. AppelsHigh dose N-driftet al. IEDM1979, pp.238- 241, 1979 SourceDrainBreakdown voltageSourceGateN N-driftPP-Breakdownnear N ExMedium dose N-driftSourceN Breakdownnear PGNDElectricfieldExN-drift DoseDrainGateEyN-driftPN P-N-drift dose (atm/cm2) is the key parameterfor breakdown voltage design ( 1e12/cm2)GNDElectricfieldExIchiro Omura Kyushu Inst. Tech.Ey
Lateral “Super Junction” MOSFETSourceGateX2 amount ofconduction edP-substrateND. Disney et al. A new 600V lateral PMOS device witha buried conduction layer, pp.41-44, ISPSD’ 03P-substrateSOI IGBTNbaseEmitterOxideEyBOXSubstrateGNDIchiro Omura Kyushu Inst. Tech.
Future Power ICsPower IC VBK in ISPSD papersFuture HV Power IC will be Digital RichPower ICTransmissionsHigh power motordrives10000er sicw PImPo / Praghce orHith taiw ulerM InswIPpo iPd Sde erol wm Po Ber / Csf es Pnan i c oBTr devPConDIP IPMHEV IPMIndustrial IPM100ICerOn board Power SupplysMax(Vin, Vout)ApplianceswPoVoltage（V）esulod1000MHigh powerIndustrial DrivesEV/HEVSOI single chip inverterVicor VIChip10KilowattPower ICCPU Power Supply(POL)wPoMobile Power SupplyerSingle chip power supplySoC10.11101001000Current（A）Max(Iin, Iout)Omura, ECPE workshop Jan. 2012Ichiro Omura Kyushu Inst. Tech.Omura, CIPS 2010
Future PossibilityIchiro Omura Kyushu Inst. Tech.
Advanced power devices Road mapDiamondWide band-gap semiconductorPlatform (SiC::2010 、GaN::2015 Diamond::2025 ）FET/ BJT/PiN/FieldemitterSiCHybrid pair platform of Si-switchingdevice and SiC diode (2013 2035）SiCIGBT/PiNMOS/SIT/SBDSilicon platform ( 2030）GaNHEMT/MOS/SBDGaAs-FETSi-IGBTSiC-SBD, cuit area SiC-SBDCircuit areaSiliconIGBT, Thyristor/PiNSiliconCMOS, MOSFET (SJ)/SBD, PiN1101001kBlocking voltage [v]10kH. Ohashi et al. “Role of Simulation Technology for the Progress in Power Devices and Their Applications,” IEEEIchiro Omura Kyushu Inst. Tech.T-ED, Vol. 60, issue 2, 2013.
Future possibility 1) Si-power devices still have much room for development toward ultimateMOSFETs and IGBTs.2) The combination of Si-switching devices and SiC freewheeling diodes willbe a significant step not only for strengthening the SiC market but also for Sidevice development.3) Si-IGBT will be replaced by SiC MOSFET in the voltage range of more than1000 V in some applications, and SiC-IGBT has the potential to be used forapplications of more than 10 kV. (Si-IGBT for volume market, SiC for high endmarket)4) GaN power devices will replace some of Si-power ICs and will be used forfaster switching applications.5) The unique properties of diamond have potential for new power devicesparticularly in high-voltage applications.6) The ultimate CMOS has the potential to be used for power integrateddevices in ICT applications.H Ohashi, I Omura - IEEE transactions on electron devices, 2013Ichiro Omura Kyushu Inst. Tech.
Related TechnologyIchiro Omura Kyushu Inst. Tech.
Examples of High Power IGBT Package42 Chips125mm15mmIchiro Omura Kyushu Inst. Tech.Shen, Omura, “Power Semiconductor Devices for Hybrid, Electric, and Fuel Cell Vehicles” Proc. Of the IEEE, Issue 4, 2007
Wafer technology(Silicon)Productivity300mm, CZ, MCZ1200V IGBT1200V PiN diodeLarge Market, Short time to marketLow voltage commodityMaterial (wafer) engineering will share the majorLow voltage high specpart of total power device design,fabrication andPE applicationHigh voltage power MOS6500V PiN diode6500V IGBTThyrisotrsSpecial Power DevicesQualitySmaller Market, Long termLong carrier lifetime150-200mm FZFunctionalityIntegration, Game changeIchiro Omura Kyushu Inst. Tech.Epi, SOI, SJ-structure etc(Pre-structured wafer)
Power electronics and micro electronicsforming Cyber-Physical SystemGeneratingHigh tingInternetDigitalEnergyCoolingSNSE-Storage networknetwork IoT, Industrie 4.0PowerelectronicsLegacy ware,Sensing,ProtocolLSI,Adv. CMOSMicroelectronicsNetworkingClusteringLegacy MicroElectronicsIntegratingIntegrationHardware Electron devices are the key technology for future energy networking New phase of electronics has started with close link between powerand micro electronics for future sustainable societyI. Omura, SIIQ report, Oct. 2012, in JapaneseIchiro Omura Kyushu Inst. Tech.
See alsoZ. John Shen, Ichiro OmuraArticle Power Semiconductor Devices for Hybrid, Electric, and FuelCell VehiclesProceedings of the IEEE 05/2007; 95(4-95):778 - 789.H. Ohashi and I. Omura “Role of Simulation Technology for theProgress in Power Devices and Their Applications,” IEEE T-ED, Vol.60, issue 2, 2013.Ichiro Omura Kyushu Inst. Tech.
IAEA-TECDOC-1681, Neutron Transmutation Doping of Silicon at Research Reactors, 2012 Neutron transmutation doping Low minority carrier (hole) injection efficiency Non-Punch-through IGBT (NPT-IGBT) 1. NTD wafer without N-buffer 2. Low minority (hole) carrier injection from P-emitter 3. Higher-conduction loss and lower switching loss 4.
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History, and Hazards J. M. Rhodes and John P. Lockwood (Eds.) 93 Cross-Scale Coupling in Space Plasmas James L Horowitz, Nagendra Singh, and James L. Burch (Eds.) 94 Double-Diffusive Convection Alan Brandt and H. J. S. Fernando (Eds.) 95 Earth Processes: Reading the Isotopic Code Asish Basu and Stan Hart (Eds.)
EDS Administration System Welcome Screen This is the first screen in the EDS Admin System. The menu on the left side of the screen provides you with a list of ta sks that you can perform and shows you where you can go (navigate) within the system. You will see the menu options that match your assigned admin role.
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Danlos Syndrome/Hypermobility EDS is associated with a higher frequency of some common gynecologic problems. EDS is associated with some rare gynecologic disorders. Pubertal maturation can worsen symptoms associated with EDS.
for use in animal nutrition. Regulation (EC) No 178/2002 laying down the general principles and requirements of food law. Directive 2002/32/EC on undesirable substances in animal feed. Directive 82/475/EEC laying down the categories of feed materials which may be used for the purposes of labelling feedingstuffs for pet animals The Animal Feed (Hygiene, Sampling etc and Enforcement) (England .
