高耐圧GaNパワーデバイス開発 - astf.or.jp

1 2 GaN ( ) 2 GaN GaN z Si MOCVD zSi AlGaN/GaN HFETGaN z AlGaN/GaN - Gate Injection Transistor (GIT) GaN z10000V AlGaN/GaN HFET 2 GaN 2 GaN Si, GaAs ( C) (fmax) (GH ) NF) RF (dB) (V/um) Imax) (A/mm)20015010050 GaNGaAsSi RF RF 2 GaN z Si zGaN zAlGaN/GaN ( 1x1013cm-2) z z 1900V GaN Si GIT 2 GaN z Si MOCVD zSi AlGaN/GaN 2 GaN Si GaN ( ) (A) (10-6/K)

2 9 30 /cm2 9 600 /cm2 7 8 25,000 /cm2 50,000 /cm2 (Wcm/K) (cm-2) 2 Si AlGaN/GaN HFET X Si(111) AlNAlGaNGaN AlNGaN : Si>GaN>AlN : Si<GaN<AlN MOCVD AlGaN/AlN GaN/AlN (deg.)X-ray Intensity (arb. units)GaN0-1-2-3+1+2+3+ 2 Si MOCVD 2 0100020003000-80 -60 -40 -20020406080 Distance from Center (mm)Hall Mobility (cm2/Vsec)Si HFET 1653 cm2/Vsec012-80-60-40-20020406080 Distance from Center (mm)Sheet Carrier Concentration (x 1013 cm 2) 2 Si AlGaN/GaN HFET (Wg= 500mm) Source Source BufferSilicon SubstrateSourceDrainGateDrainDrain FET SEM 2 AlGaN/GaN HFET DC BVoff: 350 VRon: (Ron A.)

3 Cm2)Vgs= 2 GaN z AlGaN/GaN - Gate Injection Transistor (GIT) 2 AlGaNAlGaNscbAlGaNcbpdqNEVEV 0 = =)()()(11 GaNPNGaAlPNGaAlPSPxxSPxxPE += []cAlGaNAlGaNsEEeedeNFb + += )/( et al, , , , 1999 AlGaN Al PPE: Piezoelectric polarizationPSP: Spontaneous polarization ECEFEC- AlGaN+ AlGaN- GaN+ GaNNS(GaN) >1x1013cm-2 Schottky metal0-+ (AlGaN)PPE(AlGaN)PSP(GaN) : Fixed chargeBand diagramCharge distribution AlGaN/GaN 2 GaN -GIT -Gatep-AlGaNi-AlGaNi-GaNSourceDrain Gate Injection Transistor (GIT) h<< 2 GIT -4-3-2-101234-0.

4 3-0 .2-0 .100 .10 .20 .30 .4 Depth [um]Energy [eV] 2 GIT Vg = 0V Vg > Vf of GaN-PN junction (conductivity modulation)i-AlGaNi-GaNVgs0V5 VonoffVgsp-AlGaNoffGateSourceDrainon++++ --------------------++++ 2 050100150200250300-3-2-10123456 Vgs (V)Ids (mA/mm)020406080100120gm (mS/mm)Ids (GIT) 2 gm gm (GIT)Lg=2 m, Lgd= mgm (MESFET)Ids (MESFET)GIT MESFET Ids-Vgs 2 Vp: + Imax : 200mA/mm RonA: cm2 : 800 VGIT DC 0501001502002503000246810 Vds [V]Ids [mA/mm]Vgs=5 VLg=2 m, Lgd= mVgs=4 VVgs=3 VVgs=2 VVgs=1 VVds (V)Ids (mA/mm) 200 400 600 800 1000 Vds[V]Ids[mA/mm]Lg=2 m, Lgd= mVgs=0 VVds (V)Ids (mA/mm) 2 GIT - 10210310410-110010110 2 Breakdown voltage (V)Specific On-Resistance RonA (m cm2)GaN LimitThis workGITSi LimitSi Super Junction MOSFETSi IGBT (commercial)GaN HFET(normally-off)[3][4] 2 GaN z10000V AlGaN/GaN 2 AlGaN/GaN HFET i-AlGaNi-GaN SiNPassivation Y.

5 Dora, et alEDL, , pp713, 2006N. Tipirneni, et al EDL, , pp716, 200605101520500100015002000 Lgd ( m)Breakdown Voltage (V) Lgd AlGaN/GaN HFET 1900V 2 AlGaN/GaN HFET i-AlGaNi-GaN AlN SiN AlGaN/GaNHFET AlN SiN SiN 200 2 + + + +030 100 200 300 400 500 600 Voltage [V]Current [A/cm2]SiN 1 mAlN 1 mAlN (Metal-Insulator-Metal) - 2 SiNAlN18023028033002610 Max.

6 Temperature ( C)Thickness ( m)130480-22position ( m)4-4180230330 Temperature ( C)130 AlN 500nm 1 m2 m5 m10 mSGD280 SiN 500nm 10 m2 DEG AlN 2 AlN thickness ( m)0 Thermal resistance, Rth( C/W 1234048121620 AlNSiNWg : 2 9eV (Multi-photon ionization) SEM Depth=250 2 100 m SEM 2 SiNAlN i-AlGaNi-GaN AlGaN/GaN HFET 2 SourceDrainVia-holeGate1mm SEM AlGaN/GaN HFET sourcegate10 msapphireAlN-bufferAlGaN/GaNPoly-AlNSiN5 2 020004000600080001000012000020406080 100 120 140 Lgd [um]Breakdown Voltage [V] - (Lgd))

7 Thick poly-AlNPassivationSiN PassivationVg= 2 0123456789100200040006000800010000 12000 Drain Voltage [V]Drain Current [mA/mm] Voltage [V]Drain Current [A/mm]Vgs= 1V-1V-2V-3V-4 VLg=2 m, Lgd=125 m0 VDrain Voltage [V]Drain Current [A/mm]Lg=2 m, Lgd=125 mVgs= -5 VDrain Voltage [V]Drain Current [mA/mm]10400 VRonA=186m cm2 BVds=10400 VImax=150mA/mmVp= - HFET DC 2 10210310410-110010110 2 Breakdown voltage [V]Specific On-Resistance RonA [m cm2]10510 310 4Si LimitSi Super Junction MOSFETSi IGBTGaN LimitGaN HFETN ormally-OnThis WorkUHV-HFET AlGaN/GaN HFET - GaN 2 GaN z Si MOCVD z AlGaN/GaN HFET(150A/350V) z AlGaN/GaN Gate Injection Transistor (GIT) z 10000V Vp=+ Ron A = m cm2 BVds= 800V Ron A = 186 m cm2 BVds= 10400V