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Recent Power Semiconductor Recent Power Semiconductor Recent Power Semiconductor Recent Power Semiconductor
Devices Technologies forDevices Technologies forDevices Technologies forDevices Technologies for
a Future Smart Societya Future Smart Societya Future Smart Societya Future Smart Society
Prof. Noriyuki Prof. Noriyuki Prof. Noriyuki Prof. Noriyuki IwamuroIwamuroIwamuroIwamuro
Faculty of Pure and Applied SciencesFaculty of Pure and Applied SciencesFaculty of Pure and Applied SciencesFaculty of Pure and Applied SciencesUniversity of TsukubaUniversity of TsukubaUniversity of TsukubaUniversity of Tsukuba
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Image of Future Smart CityImage of Future Smart CityImage of Future Smart CityImage of Future Smart City
Smart city: Energy saving city for making full use ofSmart city: Energy saving city for making full use ofSmart city: Energy saving city for making full use ofSmart city: Energy saving city for making full use ofadvanced technology such as IT or advanced technology such as IT or advanced technology such as IT or advanced technology such as IT or power devicespower devicespower devicespower devices
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MotorBattery Inveter
Inverter
DC-Chopper
Engine
Gen. Others
DCDCDCDC
ACACACAC
Power Conversion
from DC to AC
Power Semiconductor DevicesPower Semiconductor DevicesPower Semiconductor DevicesPower Semiconductor Devices
PCUPCUPCUPCU
1200V/400A1200V/400A1200V/400A1200V/400A
Power Semiconductor device in Toyota PriusPower Semiconductor device in Toyota PriusPower Semiconductor device in Toyota PriusPower Semiconductor device in Toyota Prius
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Gen.Gen.Gen.Gen.
ConverterConverterConverterConverter
Power LinePower LinePower LinePower Line
Power Semiconductor device in Wind turbinePower Semiconductor device in Wind turbinePower Semiconductor device in Wind turbinePower Semiconductor device in Wind turbine
1700V/450A1700V/450A1700V/450A1700V/450A~~~~1000A1000A1000A1000A
Power Semiconductor DevicesPower Semiconductor DevicesPower Semiconductor DevicesPower Semiconductor Devices
((((IGBTIGBTIGBTIGBT ModuleModuleModuleModule))))
Power Conversion Power Conversion Power Conversion Power Conversion
from AC to ACfrom AC to ACfrom AC to ACfrom AC to AC
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Power electronics applicationsPower electronics applicationsPower electronics applicationsPower electronics applications
Air Conditioner
Home Appliance
Robotics
UPS
Train
EV, HEV
Bottom line for the power conversion/power devicesBottom line for the power conversion/power devicesBottom line for the power conversion/power devicesBottom line for the power conversion/power devices
1)Higher efficiency1)Higher efficiency1)Higher efficiency1)Higher efficiency and 2)Higher ruggednessand 2)Higher ruggednessand 2)Higher ruggednessand 2)Higher ruggedness
⇒⇒⇒⇒Superior power devices are strongly requiredSuperior power devices are strongly requiredSuperior power devices are strongly requiredSuperior power devices are strongly required
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10M
1M
100 k
10k
1k
100
1010 100 1k 10 k 100 k 1M 10M 100 M
SMPSSMPSSMPSSMPS
AudioAudioAudioAudio
Inverter Air conditionerInverter Air conditionerInverter Air conditionerInverter Air conditioner
Home applianceHome applianceHome applianceHome appliance
UPSUPSUPSUPS
PowerlinePowerlinePowerlinePowerline
MOSFET
IGBT MDL
GTO Thyrisitor
RailwayRailwayRailwayRailway
Servo, Servo, Servo, Servo,
RoboticsRoboticsRoboticsRobotics
InverterInverterInverterInverter
AutomotiveAutomotiveAutomotiveAutomotive
Silicon(Si)Silicon(Si)Silicon(Si)Silicon(Si)----MOSFET, SiMOSFET, SiMOSFET, SiMOSFET, Si----IGBT widely acceptedIGBT widely acceptedIGBT widely acceptedIGBT widely accepted
Application Field of Power DevicesApplication Field of Power DevicesApplication Field of Power DevicesApplication Field of Power Devices((((2015201520152015))))
Freq
uenc
y(H
z)
Device CapacityDevice CapacityDevice CapacityDevice Capacity (VA)(VA)(VA)(VA)
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OnOnOnOn----state voltage(On resistance):state voltage(On resistance):state voltage(On resistance):state voltage(On resistance):▲▲▲▲50%, Die size:50%, Die size:50%, Die size:50%, Die size:▲▲▲▲70707070%%%%
2nd Gen.
3rd Gen.
4th Gen.
5th Gen.
6th Gen.
Area=1
A=0.71
A=0.71
A=0.43
A=0.31
1200V/100A
Device
Year
((((Courtesy: Fuji ElectricCourtesy: Fuji ElectricCourtesy: Fuji ElectricCourtesy: Fuji Electric))))
On-
stat
e vo
ltag
e(V
)
Improvement of SiImprovement of SiImprovement of SiImprovement of Si----IGBT IGBT IGBT IGBT
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0000
50505050
100100100100
150150150150
200200200200
250250250250
300300300300
1988198819881988 1990199019901990 1992199219921992 1994199419941994 1996199619961996 1998199819981998 2000200020002000 2002200220022002 2004200420042004
(年)(年)(年)(年)
チップ
厚さ(u
m)
チップ
厚さ(u
m)
チップ
厚さ(u
m)
チップ
厚さ(u
m)
600V
1200V
1700V
After 2003, Improvement of thin wafer slow downAfter 2003, Improvement of thin wafer slow downAfter 2003, Improvement of thin wafer slow downAfter 2003, Improvement of thin wafer slow down
⇒⇒⇒⇒In 2015, thickness is comparable to that in 2003In 2015, thickness is comparable to that in 2003In 2015, thickness is comparable to that in 2003In 2015, thickness is comparable to that in 2003
Breakdown voltage is not sustainable when we thin the wafer moreBreakdown voltage is not sustainable when we thin the wafer moreBreakdown voltage is not sustainable when we thin the wafer moreBreakdown voltage is not sustainable when we thin the wafer more
⇒⇒⇒⇒Si limit!Si limit!Si limit!Si limit!
Limitation of Thin Wafer TechnologyLimitation of Thin Wafer TechnologyLimitation of Thin Wafer TechnologyLimitation of Thin Wafer Technology
(Year)
thic
knes
s
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Ge・・・・First semiconductor material
・・・・μe=3900e=3900e=3900e=3900 cmcmcmcm2/VsVsVsVs
・・・・μh=1900h=1900h=1900h=1900 cmcmcmcm2/Vs
・・・・Eg ==== 0.66eV0.66eV0.66eV0.66eV Operation Temp.40404040℃℃℃℃
・・・・Eg ==== 1.12eV1.12eV1.12eV1.12eV Operation Temp 150150150150℃℃℃℃
・・・・All application
・・・・Fast switching
・・・・High Temperature operation
GaAs・・・・Eg ==== 1.42eVeVeVeV Operation temperature350350350350℃℃℃℃
・・・・LD, LED
・・・・High speed(HEMT, MESFET))))
・・・・complicated process
・・・・difficulty of bipolar device
・・・・No good passivation film
SiC
Si
GaN
Change of semiconductor device materialsChange of semiconductor device materialsChange of semiconductor device materialsChange of semiconductor device materials
Diamond
2015
Wide Band GapWide Band GapWide Band GapWide Band GapMaterialsMaterialsMaterialsMaterials
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US President B. Obama announcedUS President B. Obama announcedUS President B. Obama announcedUS President B. Obama announced
(Jan. 2014)(Jan. 2014)(Jan. 2014)(Jan. 2014)
“the advanced manufacturing institute“the advanced manufacturing institute“the advanced manufacturing institute“the advanced manufacturing institute
for energyfor energyfor energyfor energy----efficient efficient efficient efficient wide band gap wide band gap wide band gap wide band gap
semiconductorsemiconductorsemiconductorsemiconductor““““
National project of SIPNational project of SIPNational project of SIPNational project of SIP((((Strategic Strategic Strategic Strategic
Innovation Promotion Program)launchedInnovation Promotion Program)launchedInnovation Promotion Program)launchedInnovation Promotion Program)launched
for development offor development offor development offor development of wide band gap wide band gap wide band gap wide band gap
semiconductor in 2014 semiconductor in 2014 semiconductor in 2014 semiconductor in 2014
World focusing on the WBG semiconductorsWorld focusing on the WBG semiconductorsWorld focusing on the WBG semiconductorsWorld focusing on the WBG semiconductors
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Why Wide Band Gap materials? Why Wide Band Gap materials? Why Wide Band Gap materials? Why Wide Band Gap materials?
Advantage of WBGAdvantage of WBGAdvantage of WBGAdvantage of WBG device over Si onedevice over Si onedevice over Si onedevice over Si one
→Wm
= 1/10
→Ron = 1/300
•VB=E
cW
m/2
•ND=εEc2/2qV
B
•R=Wm/qμN
D
SiC DeviceSiC DeviceSiC DeviceSiC Device
・・・・Thinner nThinner nThinner nThinner n---- layer(1/10 of Si)layer(1/10 of Si)layer(1/10 of Si)layer(1/10 of Si)
・・・・High impurity densityHigh impurity densityHigh impurity densityHigh impurity density
→→→→Lower RonALower RonALower RonALower RonA
Also, higher temp. applicableAlso, higher temp. applicableAlso, higher temp. applicableAlso, higher temp. applicable
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WhyWhyWhyWhy SiCSiCSiCSiC power devices?power devices?power devices?power devices?
1111. Limit of Si power devices. Limit of Si power devices. Limit of Si power devices. Limit of Si power devices
2222. Requirement from new application field. Requirement from new application field. Requirement from new application field. Requirement from new application field
①①①①High temperature operationHigh temperature operationHigh temperature operationHigh temperature operation((((over 200over 200over 200over 200℃℃℃℃))))
②②②②Under very severe environment(Under very severe environment(Under very severe environment(Under very severe environment(ex.Spaceex.Spaceex.Spaceex.Space))))
③③③③SSSSmall and down sizemall and down sizemall and down sizemall and down size
④④④④Higher efficiencyHigher efficiencyHigher efficiencyHigher efficiency
3. History, development achievement3. History, development achievement3. History, development achievement3. History, development achievement
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Merit for high temp. operationMerit for high temp. operationMerit for high temp. operationMerit for high temp. operation
Hybrid Car(Lexus LS600h) HV Inverter system(PCU)
Less space⇒ Smaller size
Abolition of exclusive cooling system for InverterAbolition of exclusive cooling system for InverterAbolition of exclusive cooling system for InverterAbolition of exclusive cooling system for Inverter
⇒⇒⇒⇒Common use of radiator coolantCommon use of radiator coolantCommon use of radiator coolantCommon use of radiator coolant
Si IGBTSi IGBTSi IGBTSi IGBT InverterInverterInverterInverter SiC MOSFETSiC MOSFETSiC MOSFETSiC MOSFET InverterInverterInverterInverter
Ref. Denso Corp.
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Fuji Electric started the SiC device mass production in Oct, 2013.Fuji Electric started the SiC device mass production in Oct, 2013.Fuji Electric started the SiC device mass production in Oct, 2013.Fuji Electric started the SiC device mass production in Oct, 2013.
((((Matsumoto, Nagano, JapanMatsumoto, Nagano, JapanMatsumoto, Nagano, JapanMatsumoto, Nagano, Japan))))
SiC Power device mass production by SiC Power device mass production by SiC Power device mass production by SiC Power device mass production by ΦΦΦΦ6 wafer6 wafer6 wafer6 wafer
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SiC power electronics product applicationSiC power electronics product applicationSiC power electronics product applicationSiC power electronics product application
((((Produced by Mitsubishi Electric))))
((((Ref:Web of Council for Science, Technology and Innovation Ref:Web of Council for Science, Technology and Innovation Ref:Web of Council for Science, Technology and Innovation Ref:Web of Council for Science, Technology and Innovation ))))
SiC InverterSiC InverterSiC InverterSiC Inverter
Application for RailwayApplication for RailwayApplication for RailwayApplication for Railway
SiC Inverter installed in Tokyo Metro Ginza LineSiC Inverter installed in Tokyo Metro Ginza LineSiC Inverter installed in Tokyo Metro Ginza LineSiC Inverter installed in Tokyo Metro Ginza Line
(Si(Si(Si(Si----IGBT+SiCIGBT+SiCIGBT+SiCIGBT+SiC----SBD)SBD)SBD)SBD)
Power loss reduction:Power loss reduction:Power loss reduction:Power loss reduction:▲▲▲▲40%40%40%40%
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MEGA Solar PCS which 1200V All SiCMEGA Solar PCS which 1200V All SiCMEGA Solar PCS which 1200V All SiCMEGA Solar PCS which 1200V All SiC----MOSFET module is installed.MOSFET module is installed.MOSFET module is installed.MOSFET module is installed.
(Fuji Electric, May. 2014(Fuji Electric, May. 2014(Fuji Electric, May. 2014(Fuji Electric, May. 2014))))
Features:
Higher efficiency and small size
・Efficiency 98.8%
・Volume ▲20% reduction
(SiC(SiC(SiC(SiC----MOSFET+SiCMOSFET+SiCMOSFET+SiCMOSFET+SiC----SBD)SBD)SBD)SBD)
(Ref. Web of Nikkei Technology On(Ref. Web of Nikkei Technology On(Ref. Web of Nikkei Technology On(Ref. Web of Nikkei Technology On----line)line)line)line)
Also, Toyota announced the SiC power devices Also, Toyota announced the SiC power devices Also, Toyota announced the SiC power devices Also, Toyota announced the SiC power devices
will be installed in the new HEV in 2020.will be installed in the new HEV in 2020.will be installed in the new HEV in 2020.will be installed in the new HEV in 2020.
SiC power electronics product applicationSiC power electronics product applicationSiC power electronics product applicationSiC power electronics product application
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Issues to be solved in SiCIssues to be solved in SiCIssues to be solved in SiCIssues to be solved in SiC
(M.Firuhashi et al(Mitsubishi), ISPSD2013, pp.55)
Measured results of the Vth shift Measured results of the Vth shift Measured results of the Vth shift Measured results of the Vth shift
after applying Vg=+20V, 1000hrs @125after applying Vg=+20V, 1000hrs @125after applying Vg=+20V, 1000hrs @125after applying Vg=+20V, 1000hrs @125℃℃℃℃
1. Threshold instability after applying Vg
2. Improvement of on-state resistance
Vth shift is still observedVth shift is still observedVth shift is still observedVth shift is still observed
1111
10101010
100100100100
1000100010001000
100100100100 1000100010001000 10000100001000010000
Breakdown Voltage((((V))))
Ron
A(m
Ωcm
2 )
Comparison of VbrComparison of VbrComparison of VbrComparison of Vbr----RonA RonA RonA RonA
in various power devices @25in various power devices @25in various power devices @25in various power devices @25℃℃℃℃
RonA: Large difference betweenRonA: Large difference betweenRonA: Large difference betweenRonA: Large difference between
measured data and the theoretical limitmeasured data and the theoretical limitmeasured data and the theoretical limitmeasured data and the theoretical limit
0.2~0.3V0.2~0.3V0.2~0.3V0.2~0.3V
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E C
E i
E FM
E V
interface
Acceptor
E FS
x d
qV G
qV s
qV f
electrons
---
n-
p+
Source
Gate -----SiO2
SiCGate Electrode
Negative charged trappedat the interface states
Influence of interface states on MOSFETInfluence of interface states on MOSFETInfluence of interface states on MOSFETInfluence of interface states on MOSFET
(a)Energy band diagram (b)Cross section of MOSFET
Electron trapped at the interface states⇒electrons scattered⇒①μmos degrades②Vth increase
p
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(Ref. Web of Yaskawa Electric)(Ref. Web of Yaskawa Electric)(Ref. Web of Yaskawa Electric)(Ref. Web of Yaskawa Electric)
Solar PCS (4.5kWSolar PCS (4.5kWSolar PCS (4.5kWSolar PCS (4.5kW)))) Features:
Higher efficiency and small size
・Efficiency 98.%
・Volume ▲50% reduction
・Low noise
GaN power electronics product applicationGaN power electronics product applicationGaN power electronics product applicationGaN power electronics product application
Solar PCS(4.5kW) in which 600V GaN-HEMT devices are installed.
(Yaskawa Electric, Dec. 2014)
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GaNGaNGaNGaN----HEMT DevicesHEMT DevicesHEMT DevicesHEMT Devices((((IEDM2014IEDM2014IEDM2014IEDM2014))))
Device structureDevice structureDevice structureDevice structure
GaN on Si HEMT+SiGaN on Si HEMT+SiGaN on Si HEMT+SiGaN on Si HEMT+Si----MOS CascodeMOS CascodeMOS CascodeMOS Cascode
WaferWaferWaferWafer
Φ6GaN on Si HEMTΦ6GaN on Si HEMTΦ6GaN on Si HEMTΦ6GaN on Si HEMT
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Classification of SiC and GaN devicesClassification of SiC and GaN devicesClassification of SiC and GaN devicesClassification of SiC and GaN devices
For high power device, vertical structure is suitableFor high power device, vertical structure is suitableFor high power device, vertical structure is suitableFor high power device, vertical structure is suitable
⇒⇒⇒⇒SiC: High power, GaN: Low/Medium power SiC: High power, GaN: Low/Medium power SiC: High power, GaN: Low/Medium power SiC: High power, GaN: Low/Medium power
SiC: Vertical DeviceSiC: Vertical DeviceSiC: Vertical DeviceSiC: Vertical Device
Current flows in the whole regionCurrent flows in the whole regionCurrent flows in the whole regionCurrent flows in the whole region
→High current →High current →High current →High current
GaN: Lateral DeviceGaN: Lateral DeviceGaN: Lateral DeviceGaN: Lateral Device
Current flows at the surfaceCurrent flows at the surfaceCurrent flows at the surfaceCurrent flows at the surface
→Low current→Low current→Low current→Low current
Electrode
Sub.(Si)
Buffer(High resistance)
GaN
Electrode ElectrodeCurrent flow
Current flow
SiC substrate
SiC EPI
Electrode
No good GaN wafer applicableNo good GaN wafer applicableNo good GaN wafer applicableNo good GaN wafer applicable
⇒⇒⇒⇒GaN on Si structureGaN on Si structureGaN on Si structureGaN on Si structure
GoodGoodGoodGood SiC wafer applicableSiC wafer applicableSiC wafer applicableSiC wafer applicable
⇒⇒⇒⇒SiC on SiC structureSiC on SiC structureSiC on SiC structureSiC on SiC structure
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SummarySummarySummarySummary
1111. Present Status of Power Semiconductor Devices. Present Status of Power Semiconductor Devices. Present Status of Power Semiconductor Devices. Present Status of Power Semiconductor Devices
2. Recent Progress of SiC Power Devices2. Recent Progress of SiC Power Devices2. Recent Progress of SiC Power Devices2. Recent Progress of SiC Power Devices
SiCSiCSiCSiC----MOSFET Module application just started forMOSFET Module application just started forMOSFET Module application just started forMOSFET Module application just started for
high power applicationhigh power applicationhigh power applicationhigh power application
3. Recent Progress of GaN Power Devices3. Recent Progress of GaN Power Devices3. Recent Progress of GaN Power Devices3. Recent Progress of GaN Power Devices
GaNGaNGaNGaN----HEMT application just started forHEMT application just started forHEMT application just started forHEMT application just started for
low/medium power applicationlow/medium power applicationlow/medium power applicationlow/medium power application
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Thank you for your kind attentionThank you for your kind attentionThank you for your kind attentionThank you for your kind attention