Future of Wide Band Gap Power Semiconductors - … · Future of Wide Band Gap Power Semiconductors Peter Friedrichs, ... Low cost – perform ratio Silicon IGBT 30V…300V 600V 1200V

Future of Wide Band Gap Power Semiconductors Peter Friedrichs, Infineon Technologies AG

Contents

WBG power devices @ Infineon - positioning

Device technologies – from diodes towards transistors

Application benefits – does WBG pay off?

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2 2016-09-06 Copyright © Infineon Technologies AG 2016. All rights reserved.

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In a nutshell

A dynamic performance as known from low

voltage silicon can be transferred by SiC to several very high

voltages

What is the effect of those features ?

Thin, low resistive active layers

– Extended voltage range for fast/low loss (unipolar) devices

– 2-3x higher power densities

New horizons in efficiency and power

density


Level of integration

Highest performance

High cost-perform ratio

Low cost –perform ratio Silicon IGBT

30V…300V 600V 1200V 1700V+

GaN

SiC

GaN

GaN SiC

Silicon SJ

GaN

Silicon SJ

SiC

SiC

Silicon (SJ)

There has been a landscape developed for different power semiconductor materials*

Product portfolio available Product portfolio in development

Infineon Assessment

*Rupp et al. IEDM 2014


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SiC track record – example of Infineon’s history

Nearly 25 years of technology experience


SiC diode benefit - Less leads to more… by plug&play !!

SiC: low Qc

Ultrafast Si: large Qrr

Features

› No reverse recovery charge

› No forward recovery

› Purely capacitive switching

Technical benefits

› Erec close to zero

› 40-50% reduction in IGBT turn-on loss

› No voltage overshoots

› Switching losses independent from load current, switching speed and temperature

Customer benefits

› 20-30% higher output power in same form factor

› Reduced EMI

› No need for snubber

circuitry, reduced parts count

› High system reliability


Infineon´s extensive SiC Diodes discrete portfolio

Packages

Configuration

Continuous forward

current IF

TO-252

DPAK 2pin TO-220

2pin

TO-247 TO-263

D2PAK 2pin ThinPAK

8x8

Voltage Classes

600V 650V 1200V

2A – 40A


SiC diodes in power modules – mostly used in solar power applications


Infineon’s diode technology – driven by performance and reliability considerations

Standard Diode G1

› Pure Schottky Diode

– Surge current not possible

– No stable, defined breakdown

Al wire-bond

epi layer

SiC substrate

backside metalization

field stop layer

polyimide

termination

Al wire-bond

epi layer

SiC substrate

backside metalization

field stop layer

polyimide

termination

› Additional p-doped grid

› Combination of

– Schottky Diode and

– PN Diode

Surge Current Stable MPS Diode G2/3/5

A well designed grid structure enables

defined breakdown

Basic structure of Infineon’s 650V/1200V/1700V SiC diodes from Generation 2 onwards


The p-islands carrying the bipolar current make the difference for surge current conditions!

edge termination

metallization Schottky contact

Epitaxial n- drift layer

Epitaxial n+ field stop layer

High conductivity 4H SiC substrate

Schottky current = nominal operation

0

5

10

15

20

25

30

35

40

0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00VF (V)

I F (

A)

Bipolar pn diode

forward characteristic

surg

e c

urr

ent Schottky diode

forward

characteristic

Combined

characteristics

0

5

10

15

20

25

30

35

40

0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00VF (V)

I F (

A)

Bipolar pn diode


surg

e c

urr

ent Schottky diode

forward

characteristic

Combined

characteristics

Bipolar pn diode


surg

e c

urr

ent Schottky diode

forward

characteristic

Combined

characteristics

Bipolar boost


Unipolar SiC switches - What are the fundamental features we can utilize compared to IGBT’s plus diode ?

Integrated body diode, enabling higher power density and synchronous

rectification

No tail current, small and

temperature independent

switching losses

Very small reverse

recovery, negligible turn-

on delay

Linear I-V characteristic in switch and diode mode reduction of static

losses

SiC FET


SiC MOSFET Trade off

RdsonxA

Performance Robustness

Short Circuit

Cosmic Ray

Oxide lifetime

Threshold Voltage


Why does Infineon focus on the on a first glance more complex Trench based structure ?

DMOS

n-

e e e e

TMOS

n-

p e e

In 4H-SiC the Trench MOSFET is offering a higher channel conductivity than in DMOS

due to a smaller number of defects

We believe that by using a TRENCH type device we can achieve a higher robustness with this concept since there is no need to

overdrive the gate oxide in order to get a good channel conductivity


Infineon’s development status

› RDS,on*A=3,5mΩcm² (typical)

› RDS,on=45mΩ typ. @Tvj=25°C

› Increase by 50% @ 150°C

› VGS,th=4V (typical) @ID=1mA, VDS=VGS

› VF=3,5V (typical) @ID=10A, VGS=-5V

› Avalanche capable device

› Gate control window: 15V/-5V

– Gatecharge: typ. 55nC

Simultaneous achievement is the key benefit of a TRENCH based component


Energies, dvDS/dt & diD/dt=f(RG) VCC=800V, ID=25A, Tvj=25°C

Turn on Turn off

Fully dV/dt controllable


Dynamic behavior of SiC diodes (body and SBD)

› This comparison shows the turn-on losses of the exact same switch (SiC TMOS) against different diodes!

› Eon with Si PN diode is more than 3 times higher compared to SiC MOSFET body diode or a SiC-SBD.

› Note that the Rapid 1 diode is already a fast 650V diode!


The internal body diode is ready for hard commutation

Added value by combining advanced chip technologies with the right package

40mW commercial part Tj=25°C, Vds=800V, Rg=2.5 Ohm,

Vgs=-5/+20V, FWD=SiC 20A

40 mW IFX – 3pin 40 mW IFX – 4pin

-35%

-50%

› A part of the improvement is provided by the chip technology

› The right package is the key to a full utilization of SiC benefits

Tj=175°C, Vds=800V, Rg=4.5 Ohm,

Vgs=-5/+15V, FWD=SiC 20A

-10%

-40%


CoolSiC™ MOSFET First products


New type Designation for Modules


Driver IC recommendation for SiC MOSFET lead products - 1EDI Compact Family

› Features of EDI Compact fitting to the SiC MOSFETs from Infineon:

– Coreless transformer designed for highest dv/dt – CMTI 100kV/µs

– Infineon’s MOSFET is compatible with IGBT gate drive windows – specified Ron available at VGS=+15V

– Short propagation delay and filter time for up to 4MHz switching (D=0.5), smallest temperature drift and tight propagation delay matching

– Separate sink and source, Miller Clamp Option

– Functional isolation for 1200V

GND1

IN+

IN-

VCC1

OUT+

VCC2

GND2

OUT-

+3V3

SGND

IN

+15V

2R2

4µ7100n

3R3

-5V4µ7

0V


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SiC in UPS

› Costs of a UPS unit need to include operation as well

Power electronics are very small portion of overall costs

Improved efficiency is main goal!

costs related to power electronics

costs related to efficiency


Cost analysis in brief

› 250kVA UPS system operating 24/7 at 50% load

› Total Cost of Ownership (TCO)

– Invest: cost distribution of whole system

– Operation: efficiency-related costs (power losses, plus 40% cooling)

Break-even within one year

100.000 €

110.000 €

120.000 €

130.000 €

140.000 €

150.000 €

160.000 €

0 2 4 6 8

To

tal c

os

t o

f o

wn

ers

hip

operation period [years]

2 Level Si

3 Level NPC 1

2 Level SiC

[10 ct/kWh]

Savings > 10,000€ for UPS systems after 5 years


› 3 phase solar inverter system, 15…20kW

› Reference technology: Si IGBT4, 3-Level topology (NPC2)

› Alternatives: 1200V SiC FET, 3-level- or 2-level topology

› Analysis

– Technical: interaction of power modules with magnetics, heat sink

– Cost: impact of power modules, magnetics, heat sink

SiC benefit in Solar

Control Unit

+ PCB

Booster

stage

DC-link Inverter Choke Filter

Housing/

Heatsink

=

=

=

=

=

~3ACA

B


Expected BOM benefit in Solar

› Clear bill of material benefit for various technical solutions

Higher costs for power modules in all scenarios

More than compensated by savings in magnetics and heat sink

-20%

Savings ~ 20% for solar inverter

These two scenarios assume more SiC area in order to reduce losses

compensated by

heatsink saving


IGBT

Si MOSFET

SiC

GaN

Automotive application requirements are met best with IGBTs and SiC MOSFETS

fsw [Hz]

Pout [W]

1k

1k 10k 100k 1M

1M

10k

SiC Si

100k

1200V

250V

Auxi-liaries

Inverter

DC/ DC

OBC

Booster


So how the future of Wide Band Gap will

look like ?

Infineon expects a significant impact from WBG in power semiconductors on long term scale


Infineon has acquired International rectifier in 2014

GaN on silicon technology was one of the key rationales

Infineon plans to acquire Wolfspeed and the material business from Cree – become no.1 power and RF based on SiC

Thank you very much for your kind

attention! Questions are very welcome!

Documents

Future of Wide Band Gap Power Semiconductors - … · Future of Wide Band Gap Power Semiconductors Peter Friedrichs, ... Low cost – perform ratio Silicon IGBT 30V…300V 600V 1200V