Power Semiconductors for Power Electronics Applications Munaf Rahimo, Corporate Executive Engineer Grid Systems R&D, Power Systems ABB Switzerland Ltd, Semiconductors
CAS-PSI Special course Power Converters, Baden
Contents !
Power Electronics and Power Semiconductors
!
Understanding the Basics
!
Technologies and Performance
!
Packaging Concepts
!
Technology Drivers and Trends
!
Wide Band gap Technologies
!
Conclusions
Power Electronics and Power Semiconductors Semiconductors FWD1
S1
S3
S5
S2
S4
S6
VDC
Power Electronics Applications are
!.
.. an established technology that bridges the power industry with its needs for flexible and fast controllers DC Transportation
AC
=
Grid Systems
4
] 10 A [ t n e 3 r r 10 u C e c 102 i v e D
Traction
=
~ ~
~ ~
HVDC
FACTS Power Supply
Industrial Drives
Motor Drive
HP
101
Automotive DC AC AC DC AC(V1, 1, #1) AC(V 2, DC(V1) DC(V2)
Lighting 100 101
102
103
104
2, #2)
AC M
Power Electronics Application Application Trends !
Traditional: More Compact and Powerful Systems
!
Modern: Better Quality and Reliability
!
Efficient: Lower Losses
!
Custom: Niche and Special Applications
!
Solid State: DC Breakers, Transformers
!
Environmental: Renewable Energy Sources, Electric/Hybrid Cars
The Semiconductor Revolution Sub-module section PIN
Wafer
System Valve
Module
IGBT
1947: Bell`s Transistor
Today: GW IGBT based HVDC systems
Semiconductors, Towards Higher Speeds & Power !
It took close to two decades after the invention of the solid-state bipolar transistor (1947) for semiconductors to hit mainstream applications
!
The beginnings of power semiconductors came at a similar time with the integrated circuit in the fifties
!
Both lead to the modern era of advanced DATA and POWER and POWER processing
!
While the main target for ICs is increasing the speed of speed of data processing, for power devices it was the controlled power handling handling capability
!
Since the 1970s 1970s,, power semiconductors have benefited from advanced Silicon material and technologies/ processes developed for the much larger and well funded IC applications and markets
Kilby`s first IC in 1958
Robert N. Hall (left) at GE demonstrated the first 200V/35A Ge power diode in 1952
The Global Semiconductor Market and Producers Pr oducers
Power Semiconductors; the Principle Power Semiconductor
Current flow direction
Switches
Rectifiers
(MOSFET, IGBT, Thyistor)
(Diodes)
Power Semiconductor Device Main Functions
Logic Device
!
Main Functions of the power device: !
Support the off-voltage (Thousands of Volts)
High Power Device
Switch
Silicon Switch/Diode Classification Si Power Devices
BiMOS
BiPolar Thyristors GTO/IGCT Triac
Current drive ! up to 10kV !
BJT
!
Current drive ! up to 2kV
PIN Diode
UniPolar
IGBT (Lat. & Ver.) Ver.)
!
Voltage drive !up to 6.5kV
MOSFET (Lat. & Ver.)
JFET
!
Voltage drive ! few 100V
!
Voltage drive !up to 1.2kV
SB Diode
Evolution of Silicon Based Power Devices PCT/Diode
Bipolar Technologies
evolving
GTO
IGCT evolving
BJT
MOSFET evolving
MOS Technologies
IGBT evolving
Ge
!
Si
Silicon, the main power semiconductor material !
Silicon is the second most common chemical element in i n the crust crus t of the earth ea rth (27.7% (27.7 % vs. 46.6% 46. 6% of Oxygen)
!
Stones and sand are mostly consisting of Silicon and Oxygen (SiO 2)
!
For Semiconductors, we need an almost perfect Silicon crystal
!
Silicon crystals for semiconductor applications are probably the best organized structures on earth
!
Before the fabrication of chips, the t he semiconductor wafer is doped with minute amounts of foreign atoms (p “B, Al” or n “P, As” type doping)
Power Semiconductor Processes !
It takes basically the same technologies to manufacture power semiconductors like modern logic devices like microprocessors
!
But the challenges are different in terms of Device Physics and Physics and Application Critical Dimension
Min. doping concentration
Max. Process Temperature*
Logic Devices
0.1 - 0.2 m
1015 cm-3
1050 - 1100°C (minutes)
MOSFET, IGBT
1-2 m
1013 - 1014 cm-3
1250°C (hours)
10 -20 m
< 1013 cm-3
1280-1300°C(days)
Device
Thyristor, GTO, IGCT
melts at 1360°C
!
Doping and thickness of the silicon must be tightly controlled (both in % range)
!
Because silicon is a resistor, device thickness must be kept at absolute minimum
Power Semiconductors Understanding The Basics
! without
diving into semiconductor physics ! " # "! #
!
ionising radiation #
#
!
#
" # " #
electron “knocked out of orbit” E = energy o f electron
!"#$%!&'"# )*#$
)*#$ +*, # & %
-*.*#!/ )*#$
allowable energy levels
$
nucleus
$ & %
!"0/ )*#$ "
r = di stance from nucleus
+
!
Si
!
!
Si
!
! ! !
!
Si
!
!
!
Si
!
!
Si
!
+
+
+
Conduction Band
!
!
Si
!
+
+
+
+
Si
Si
!
+
Si
Conduction Band
Si
!
Valence Band
!
Band Gap Valence Band
!
Si
!
Conduction Band
Si
Valence Band
!
! Metal -cm) ( ! " 10 -6 ! -cm)
Semiconductor -cm) ( ! " 10 10 2 #6 ! -cm)
Insulator -cm) ( ! " 10 10 16 ! -cm)
Power Semiconductors, Semiconductors , S. Linder, EPFL Press
The Basic Building Block; The PN Junction electric field p-type
!
Anode
! ! !
! ! !
! !
! !
!
!
! !
!
!
! ! !
!
!
!
!
+
!
!
! !
! !
!
! !
! !
! !
! !
!
! !
!
!
n-type
+
! !
!
!
+
+
+
+
+
+
+
+
+
+
+ +
+
+
+ +
junction + donors
EC
! acceptors
holes
electrons
EF
No Bias
EV Forward Bias P(+)N(-) Space-charge region abolished and a current starts to flow if the external voltage exceeds the “builtin” voltage ~ 0.7 V
Reverse Bias P(-)N(+) Space-charge region expands and
e h
+
+
Cathode
+ +
+
The PIN Bipolar Power Diode The low doped drift (base) region is the main differentiator differentiat or for power devices (normally n-type)
Poisson’s Equation for Electric Field Charge Density Permittivity
The Power Diode in Reverse Blocking Mode 0.000005
V pt 0.000004
V bd
) 0.000003 p m A ( t n e r r u C0.000002
Is 0.000001
0
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
Voltage (Volt)
Vbd
V pt
13
=
=
5. 34 ! 10
7. 67 ! 10
"12
N D
"3/ 4
N DW B
Non - Punch Through Breakdown Voltage Punch Through Voltage
• All the constants on the right hand side of the above equations have units which will result in a final unit in (Volts).
Power Diode Reverse Blocking Simulation (1/5) 1.0E+19
2.1E+05
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C
1.8E+05
]
1.5E+05 m
c / V [ 1.2E+05 d l e i F 9.0E+04 i c r t c e 6.0E+04 l E
VR=100V
1.0E+13
3.0E+04
Electric Field 1.0E+12
0.0E+00 0
100
200
300
depth [um]
400
500
600
Power Diode Reverse Blocking Simulation (2/5) 1.0E+19
2.1E+05
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C
1.8E+05
]
1.5E+05 m
c / V [ 1.2E+05 d l e i F 9.0E+04 i c r t c e 6.0E+04 l E
VR=1000V
1.0E+13
3.0E+04
Electric Field 1.0E+12
0.0E+00 0
100
200
300
depth [um]
400
500
600
Power Diode Reverse Blocking Simulation (3/5) 1.0E+19
2.1E+05
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C
1.8E+05
]
1.5E+05 m
c / V [ 1.2E+05 d l e i F 9.0E+04 i c r t c e 6.0E+04 l E
VR=2000V
Electric Field
1.0E+13
3.0E+04
1.0E+12
0.0E+00 0
100
200
300
depth [um]
400
500
600
Power Diode Reverse Blocking Simulation (4/5) 1.0E+19
2.1E+05
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C
1.8E+05
]
1.5E+05 m VR=4000V
Electric Field
c / V [ 1.2E+05 d l e i F 9.0E+04 i c r t c e 6.0E+04 l E
1.0E+13
3.0E+04
1.0E+12
0.0E+00 0
100
200
300
depth [um]
400
500
600
Power Diode Reverse Blocking Simulation (5/5) 1.0E+19
2.1E+05 VR=7400V
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C
1.8E+05
IR=1A
]
Electric Field
1.5E+05 m
c / V [ 1.2E+05 d l e i F 9.0E+04 i c r t c e 6.0E+04 l E
1.0E+13
3.0E+04
1.0E+12
0.0E+00 0
100
200
300
depth [um]
400
500
600
Power Diode in Forward Conduction Mode 5000
4500
4000
V f
3500
=
V pn + VB
+
Vnn
) 3000 p m A ( t 2500 n e r r u C2000
Vo
1500
1/Ron 1000
500
0 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
Voltage (Volt)
V B
=
2 kT W B 2 ( ) q 2 La
Base (Drift) Region Voltage Drop
1.5
Power Diode Forward Conduction Simulation (1/5) 1.0E+19
Cathode
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C1.0E+13
Anode
e-
h+
1.0E+12 0
100
200
300
400
500
600
90
Forward Conduction Simulation (2/5)
80 70 60 ] 50 A [ F I 40 30
1.0E+19
20
eDensity hDensity DopingConcentration
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C1.0E+13
10 0 0.0
0.5
1 .0 .0
1.5
2.0
2.5
VF [V]
1.0E+12 0
100
200
300
400
500
600
3 .0 .0
3.5
90
Forward Conduction Simulation (3/5)
80 70 60 ] 50 A [ F I 40 30
1.0E+19
20
eDensity hDensity DopingConcentration
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C1.0E+13
10 0 0. 0 0 .5 .5
1 .0 .0
1 .5 .5
2. 0 2 .5 .5
VF [V]
1.0E+12 0
100
200
300
400
500
600
3 .0 .0
3 .5 .5
90
Forward Conduction Simulation (4/5)
80 70 60 ] 50 A [ F I 40 30
1.0E+19 eDensity hDensity DopingConcentration
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C1.0E+13
20 10 0 0.0
0.5
1.0
1.5
2.0
2.5
VF [V]
1.0E+12 0
100
200
300
400
500
600
3.0
3.5
90
Forward Conduction Simulation (5/5)
80 70 60 ] 50 A [ F40 I 30
1.0E+19 eDensity hDensity DopingConcentration
] 1.0E+18 3 m c [ 1.0E+17 n o i t a r 1.0E+16 t n e c n 1.0E+15 o C r e 1.0E+14 i r r a C1.0E+13
20 10 0 0. 0 0 .5 .5
1 .0 .0
1 .5 .5
2. 0 2 .5 .5
VF [V]
1.0E+12 0
100
200
300
400
500
600
3 .0 .0
3 .5 .5
Power Diode Reverse Recovery !
Reverse Recovery: Transition from the conducting to the blocking state Stray Inductance
VDC (2800V)
Diode
inductive load
IGBT
Reverse Recovery Simulation (1/5) 1E+19
3.5E+05
1E+18
3.0E+05 Anode
Cathode
] 3 - 1E+17 m c [ n 1E+16 o i t a r t n 1E+15 e c n o 1E+14 c
2.5E+05
] m c 2.0E+05 / V [ d l e 1.5E+05 i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
100
200
300
400
500
600
Reverse Recovery Simulation (2/5) 1E+19
3.5E+05
1E+18
3.0E+05
] 3 - 1E+17 m c [ n 1E+16 o i t a r t n 1E+15 e c n o 1E+14 c
2.5E+05
] m c 2.0E+05 / V [ d l e 1.5E+05 i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
100
200
300
400
500
600
Reverse Recovery Simulation (3/5) 1E+19
3.5E+05
1E+18
3.0E+05
] 3 - 1E+17 m c [ n 1E+16 o i t a r t n 1E+15 e c n o 1E+14 c
2.5E+05
] m c 2.0E+05 / V [ d l e 1.5E+05 i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
100
200
300
400
500
600
Reverse Recovery Simulation (4/5) 1E+19
3.5E+05
1E+18
3.0E+05
] 3 - 1E+17 m c [ n 1E+16 o i t a r t n 1E+15 e c n o 1E+14 c
2.5E+05
] m c 2.0E+05 / V [ d l e 1.5E+05 i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
100
200
300
400
500
600
Reverse Recovery Simulation (5/5) 1E+19
3.5E+05
1E+18
3.0E+05
] 3 - 1E+17 m c [ n 1E+16 o i t a r t n 1E+15 e c n o 1E+14 c
2.5E+05
] m c 2.0E+05 / V [ d l e 1.5E+05 i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
100
200
300
400
500
600
Lifetime Engineering of Power Diodes !
Recombination Lifetime: Average value of time (ns - us) after which free carriers c arriers recombine (= disappear).
!
Lifetime Control: Controlled introduction of lattice defects recombination " shaping of the carrier distribution
" enhanced
carrier
ON-state Carrier Distribution Distribution N O I T A R T N E C N O C
without lifetime control
with local lifetime control DEPTH
Power Diode Operational Modes I
•
Reverse Blocking State • •
•
•
•
I 25C 125C V bd
Stable reverse blocking Low leakage current
Forward Conducting State •
Low on-state losses
•
Positive temperature coefficient
+ve Temp. Co.
V pt
125C Is
IF
25C -ve Temp. Co.
V
V
Forward Forwa rd Char Character acteristic istics s
Reverse Rever se Char Character acteristi istics cs
Vf
Turn-On (forward recovery) •
Low turn-on losses
•
Short turn-on time
•
Good controllability
Turn-Off (reverse recovery) •
IF
Vpf Current
trr
Short turn-off time
•
Soft characteristics
dir/dt
dv/dt di/dt Voltage
dif/dt
Vf
Low turn-off losses
•
IF
VR Qrr Voltage
Current V pr t F
Forward Recovery
I pr time
time
Reverse Recovery
Power Semiconductors Technologies and Performance
Silicon Power Semiconductor Device Concepts 1000s of volts PCT
IGBT
10s of volts MOSFET 108
GTO / GTO / GCT GCT
BJT
and the companion Diode
] W [ r e w 6 o 10 P n o i s r e v 104 n o C
In red are devices that are in “design-in life”
T C P
IGCT
Today`s evolving Silicon based devices
IGBT
MOSFET
102 101
102
103
104
Conversion Frequency [Hz]
Silicon Power Semiconductor Switches Technology
Device Character
Control Type
Bipolar (Thyristor) Thyristor , GTO, GCT GTO, GCT
Low on-state losses High Turn-off losses
Current Controlled
Bipolar (Transistor)
Medium on-state losses Medium Turn-off losses
Current Controlled
Medium on-state losses Medium Turn-off losses
Voltage Controlled
High on-state losses Low Turn-off losses
Voltage Controlled
BJT,, Darlington BJT Da rlington BiMOS (Transistor) IGBT Unipolar (Transistor) MOSFET,, JFET MOSFET
(“High” control power)
(“High” control power)
(Low control power)
(Low control power)
The main High Power MW Devices: LOW LOSSES Gate n
p
n-
p
PCT/IGCT
A n o d e
Cathode Gate n Cathode
p
n-
p
IGBT Hole Drainage
n o i t Plasma in IGCT for low losses a r t n e c nn o p Plasma in IGBT C n-
• PCTs & IGCTs: IGCTs: optimum carrier distribution for lowest losses
p
The High Power Devices Developments
Power Semiconductor Power Ratings IGBT IGBT chip chip T j
Pheat
T j Rthjc
Insulation and baseplate Heatsink
Rthcs Rthsa ambient Ta
Rthja
Performance Requirements for Power Devices !
!
!
Power Density Handling Capability: !
Low on-state and switching losses
!
High operating temperatures
!
Low thermal resistance
(technology curve: traditional focus)
Controllable and Soft Switching: !
Good turn-on turn-on controllability controllability
!
Soft and controllable turn-off and and low EMI
Ruggedness and Reliability: !
High turn-off current capability
!
Robust short circuit mode circuit mode for IGBTs
!
Good surge current capability current capability
!
Good current / voltage sharing for sharing for paralleled / series devices
!
Stable blocking behaviour and and low leakage current
!
Low “Failure In Time” FIT FIT rates rates
Power Semiconductor Voltage Ratings
V DRM
VDWM
VDSM VDPM
VRPM VRWM
•
VDRM – Maximum Direct Repetitive Voltage
•
VRRM – Maximum Reverse Repetitive Voltage
•
VDPM – Maximum Direct Permanent Voltage
•
VRPM – Maximum Reverse Permanent Voltage
•
VDSM – Maximum Direct Surge Voltage
•
VRSM – Maximum Reverse Surge Voltage
V RRM
VRSM
Cosmic Ray Failures and Testing !
Interaction of primary cosmics with magnetic field of earth “ Cosmics are more focused to the magnetic poles”
!
Interaction with earth atmosphere: atmosphere: !
!
! particles
!
Increase of particle density
!
Cosmic flux dependence of altitude
in the primary cosmic particle
Terrestrial cosmics
secondary cosmics
earth
Terrestrial cosmic particle species: !
!
Cascade of secondary, tertiary upper atmosphere
muons, neutrons, protons, electrons, pions
atmosphere
Typical terrestrial cosmic flux at sea level: 20 neutrons per cm2 and h n
p
-
•
•
+
Failures due to cosmic under blocking condition without precursor Statistical process and
Power Semiconductor Junction Termination
Anode
Cathode
Metal source contact Passivation Metal source contact
Passivation
N+ P+ Diffusions
Guard rings
N - Base (High Si Resistivity) N+
Planar technology
Bevel
N - Base (High Si Resistivity) Resistivity) P+
P+
Moly Conventional technology
The Insulated Gate Bipolar Transistor (IGBT)
cut plane
IGBT cell approx. 100’000 per cm2
How an IGBT Conducts (1/5) Emitter
+ Switch „OFF „OFF“: “: No mobile carriers (electrons or holes) in substrate. No current flow.
Collector
How an IGBT Conducts (2/5) Emitter
+
Turn-on: Application of a positive voltage between Gate Gate and and Emitter
Collector
3.3kV IGBT output IV curves
How an IGBT Conducts (3/5) Emitter
Current flow
The emitter supplies electrons through the lock into the substrate.
+
The anode reacts by supplying holes into the substrate
Collector
A MOSFET has only N+ region, so no holes are supplied and the device operates in Unipolar mode
How an IGBT Conducts (4/5) Emitter
Current flow
+ Electrons and holes are flowing towards each other (Drift and diffusion)
Collector
How an IGBT Conducts (5/5) Emitter
Current flow Electrons and holes are mixing to constitute a quasi-neutral plasma. With plenty of mobile carriers, current can flow freely and the device is conducting (switch on)
+
Collector
3.3kV IGBT Switching Performance: Test Circuit Stray Inductance
VDC (1800V)
Diode
inductive load
IGBT
Plasma extraction during turn-off (1/5) 1E+18
3.0E+05 Cathode (MOS-side)
1E+17
2.5E+05
] 3 m1E+16 c [ n o i t 1E+15 a r t n e c n 1E+14 o c
Anode plasma, e
!
2.0E+05 ]
m c / V [ 1.5E+05 d l e i F E 1.0E+05
h
Buffer
N-Base (Substrate)
1E+13
5.0E+04
1E+12
0.0E+00 0
50
100
150
200 250 depth [um]
300
350
400
Plasma extraction during turn-off (2/5) 1E+18
2.5E+05
1E+17
2.0E+05
] 3 m1E+16 c [ n o i t 1E+15 a r t n e c n 1E+14 o c
] m c 1.5E+05 / V [ d l e i 1.0E+05 F E 5.0E+04
1E+13
1E+12
0.0E+00 0
50
100
150
200
250
depth [um]
300
350
400
Plasma extraction during turn-off (3/5) 1E+18
3.0E+05
1E+17
2.5E+05
] 3 m1E+16 c [ n o i t 1E+15 a r t n e c n 1E+14 o c
2.0E+05 ]
m c / V [ 1.5E+05 d l e i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
50
100
150
200
250
depth [um]
300
350
400
Plasma extraction during turn-off (4/5) 1E+18
3.0E+05
1E+17
2.5E+05
] 3 m1E+16 c [ n o i t 1E+15 a r t n e c n 1E+14 o c
2.0E+05 ]
m c / V [ 1.5E+05 d l e i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
50
100
150
200
250
depth [um]
300
350
400
Plasma extraction during turn-off (5/5) 1E+18
3.0E+05
1E+17
2.5E+05
] 3 m1E+16 c [ n o i t 1E+15 a r t n e c n 1E+14 o c
2.0E+05 ]
m c / V [ 1.5E+05 d l e i F E 1.0E+05
1E+13
5.0E+04
1E+12
0.0E+00 0
50
100
150
200
250
depth [um]
300
350
400
3.3kV IGBT Turn-on and Short Circuit Waveforms IC=62.5A, VDC=1800V VDC=1800V
250
2400
200
Turn-on waveforms
2000 r
] V150 , [ ] e A [ g t t a n l 100 e o r r V u e C t a 50 G
e 1600 t t ] i
V [ m E e g 1200 r a o t t l c o e l l V 800 o C
0
400
-50
0 1.0
2.0
3.0
4.0
5.0
6.0
time [us] 450
Short Circuit
VGE=15.0V, VGE=15.0V, VDC=1800V
2500
400
2250
350
2000
] 300 V , [ ] e A [ g250 t t a n l 200 e o r r V u e 150 C t a G100
50
1750 r e t t i ] V 1500 m [ E e r g 1250 a o t t l c o 1000 l e l V o 750 C 500
Power Semiconductors Packaging Concepts
Power Semiconductor Device Packaging •
What is Packaging ?
•
A package is an enclosure for a single element, an integrated circuit or a hybrid circuit. It provides hermetic or non-hermetic protection, determines the form factor, and serves as the first level interconnection externally for for the device by means of package terminals. [Electronic Materials Handbook]
•
plastic housing
Package functions in PE
copper terminal
epoxy
•
Power and Signal distribution
•
Heat dissipation
metalization
bond wires gel
chip
solder
substrate baseplate
•
HV insulation
•
Protection
Power Semiconductor Device Packaging Concepts “Insulated” Devices
Mounting
heat sink galvanically insulated from power terminals #
Failure Mode Markets
Power range
all devices of a system can be mounted on same heat sink
open circuit after failure
Industry Transportation T&D typically 100 kW - low MW
Press-Pack Devices
heat sinks under high voltage #
every device needs its own heat sink
fails into low impedance state
Industry Transportation T&D MW
Insulated Package for 10s to 100s of KW
Low to Medium Power Semiconductor Packages
Discrete Devices
Standard Modules
Insulated Modules •
Used for industrial and transportation applications (typ. 100 kW - 3 MW)
•
Insulated packages are suited for Multi Chip packaging IGBTs IGBTs
package with semiconductors semiconductors inside (bolted to heat sink)
power & control terminals
heat sink (water or air cooled)
Press-Pack Modules
power terminals (top and bottom of module)
current flow package with semiconductors inside
heat sink (water or air cooled) control terminal
Power Semiconductors Technology Drivers and Trends Trends
Power Semiconductor Device Technology Platforms active area (main electrode) gate pad (control electrode)
junction termination (“isolation of active area”)
substrate (silicon)
Power Semiconductor Package Technology Platforms Heat dissipation • Interconnections • Advanced cooling concepts Pheat
IGBT chip T j
Electrical distribution • Interconnections • Power / Signal terminals • Low electrical parasitics
T j Rthjc
Insulation and baseplate Rthcs
Heatsink
Rthja
Rthsa ambient Ta
Typical temperature cycling curve !"#%-
High Voltage Insulation • Partial Discharges • HV insulating • Creepage distances
!"#%,
smaller size, lower complexity
!"#%+
s e l c y c f o º N
!"#%*
!"#%)
Encapsulation/ protection • Hermetic / non-hermetic • Coating / filling materials
!"#%(
!"#%'
greater size, higher complexity
!"#%!
!"#%&
!"#$! !&
Junction temperature excursion (ºC)
! &&
Powerful, Reliable, Compact, Application specific
Overcoming the Limitations (the boundaries) The Power Power = Von Ic or
Von = Ron
T j,max – T j,amb Rth
The Margins Pmax = Vmax.Imax, Controllability, Reliability The Application Topology opolog y, Frequency Frequency,, Control, Control, Cooling Coolin g
Technology Drivers for Higher Power (the boundaries) I Area
Larger Area
Integration
Larger Devices
Termination/Active HV, RC, RB
Extra Paralleling
I Integration
New Tech.
Absolute
Reduced Losses
Increased Margins
Carrier Enhancement
Increasing Device Power
Latch-up / Filament Protection
Thickness Reduction (Blocking)
Density
Controllability,, Softness & Scale Controllability
V.I Losses
New Technologies
Vmax.Imax SOA
!T/Rth
Traditional Focus
Temperature
Improved Thermal
The Bimode Insulated Gate Transistor (BIGT) integrates an IGBT & RC-IGBT in in one structure to eliminate snap-back effect BIGT Wafer Backside
IGBT Turn-off Diode Reverse Recovery
Wide Bandgap Bandgap Technologies echnologies ABB SiC 4.5kV PIN Diodes for HVDC (1999)
Wind Bandgap Semiconductors: Long Term Potentials Silicon
4H-SiC
GaN
Diamond
eV
1.12
3.26
3.39
5.47
MV/cm
0.23
2.2
3.3
5.6
–
11.8
9.7
9.0
5.7
cm /V·s
2
1400
950
800/1700*
1800
rel. to Si
1
1300/2700*
9000
Parameter Band-gap Eg Critical Field Ecrit Permitivity !r Electron Mobility "n 3
BFoM: !r ·"n·Ecrit
Intrinsic Conc. n i Thermal Cond. #
-3
cm
1.4·10
W/cm·K
1.5
* sign significan ificantt diff differe eren nce betw between een bulk an and 2DE 2DEG G
! !
Higher Blocking Lower Losses Lower Leakage
! !
500 10
-9
-10
8.2·10 3.8
1.9·10
1.3/3**
-22
1·10
20
** differe ifferen nce betw between een epi epi and and bu bulk
Higher Power Wider Frequency Range
SiC Switch/Diode Classification and Issues SiC Power Devices
BiMOS
BiPolar
Thyristors 5kV~".
Bipolar Issues ! Bias Voltage !
!
Bipolar Issues ! Current Drive
Diode 5kV ~ ".
UniPolar
IGBT 5kV~".
BJT 600V~10kV
Defect Issues ! High Cost !
JFET 600V~10kV
MOSFET 600V~10kV
!
MOS Issues ! Bipolar Issues ! Bias Voltage
!
Normally on
!
MOS Issues
Diode 600V~5kV
SiC Unipolar Diodes vs. Si Bipolar Diode 1700V Fast IGBTs with SiC Diodes during turn-on
Si diode
SiC diodes
Conclusions !
Si Based Power semiconductors are semiconductors are a key enabler for modern and future power electronics systems including grid systems
!
High power semiconductors devices and new system topologies are topologies are continuously improving for achieving higher power, improved efficiency and reliability and better controllability
!
The Diode, PCT, IGCT, IGBT and IGBT and MOSFET continue to evolve for achieving future system targets with the potential for improved power/performance through further losses reductions, higher operating temperatures temperatures and integration solutions
!
Wide Band Gap Based Power Devices offer many performance advantages with strong potential for very high voltage applications
