Prospects and Challenges of Modern Semiconductor Technologies in Power Electronic Applica;ons

Transcription

1 Prospects and Challenges of Modern Semiconductor Technologies in Power Electronic Applica;ons Microwave Integrated Circuits and Systems Workshop on RF, analog, millimeter wave integrated circuits and systems Technion, July 30-31, 2013 Ingmar Kallfass

2 Outline Key applica;ons of power electronics Where power electronics meet microwaves Power semiconductors compared: Si, SiC, GaN Prospects and challenges 2

3 KEY APPLICATIONS OF POWER ELECTRONICS 3

4 Power Electronics A Defini;on Power Electronics is the technology associated with the efficient conversion, control and condiloning of electric energy from the source to the load. It is the enabling technology for the genera;on, distribu;on and efficient use of electrical energy. [Catrene2013] Low voltage Several V 600 V Consumer appliances IT power supplies ligh;ng Medium voltage 600 V 1.2 kv renewables and sustainable energy electrical drive trains for cars solar panel converters motor drives robo;cs High voltage 2 kv tens of kv electrical power transmission drives for electrical trains [Rohm2011] 4

5 5 Mo;va;on: Energy Reduc;on of CO 2 emissions Nuclear phaseout in Germany EU energy efficiency plan: by 2020 achieve 20% reduc;on of greenhouse gases 20% reduc;on of energy consump;on 20% increase of renewable energies in energy genera;on 20% of final energy consump;on in EU is electrical German federal gov.: 1 Million ecars by 2020 require 3 TWh/a

6 ECPE- Roadmap (European Center for Power Electronics) Parameter (KPI = Key Performance Indicators ) goal: Improvement by 2020 by a factor of Power density (kw/l) 2-3 Power-to-mass ratio (kw/kg) 2 Efficiency / relative loss (%) 3 Relative cost (kw/eur) 2-3 Failure rate (1/h) 3 Requires the development of a full technology chain: Material, power semiconductor, circuit design, packaging, passive components, converter module, design methods 6

7 Mo;va;on: Supply Power for ICT Data volume in Mio. GB 100 Bundesnetzagentur 2010/ Year 2011: GSM/UMTS base stations 30% efficiency Power consumption: 1500 W [Ambacher2013] 7

8 Efficiency GeneraLon I AC/AC DistribuLon II AC/DC/AC III AC/DC/AC ConsumpLon IV AC/DC V DC/DC (Source: Infineon Technologies AG) Loss 20 % 60 % 15 % 20 % Total loss: %!!! 8

9 WHERE POWER ELECTRONICS MEET MICROWAVES 9

10 Wavelength 40V/4V DC/DC, Wicht 2013 E- band LNA, Dyskin x 1 mm2 Power ca. 8 x 8 cm MHz λeff EMC: trise = 1 ns è f=350 MHz è 0.16λeff Mostly ;me domain analysis I t,v t, S = P + iq d/dt slopes Thermo- electrical analysis () () GHz 2.1 λeff Rule of thumb: >0.05λeff è consider distributed effects Mostly frequency domain analysis V+ V a=, b =, P = a2 b2 Z0 Z 0 Reflec;on and transmission parameters Full- wave EM analysis Frequency

11 EMC in Automo;ve Electronics Numerous and distributed electronic sensor, control and power units Data bus (e.g. CAN) trise typ. 20 ns MOSFET (125 ns IGBT) fmax = 17.5 MHz (2.8 MHz) λeff 14.5 m (90.5 m) Car body (4m) 0.28 λeff Reflec;ons/Resonances Crosstalk 11 Illustra;on:

12 EMC in Microwave Applica;ons PLL Supply modula;on Phase noise n DC Supplies Clock of switched mode regulators Unwanted harmonics Intermodul a;on Instabili;es Spurs in radar or communica;on signal 12

13 Galvanic Isolated Integrated Gate Drivers Photonic Couplers Transformers (MHz) Drive- by- Microwave (GHz) RF frequencies significantly reduce the size of components Problem: High power technologies not designed for/tested at microwave Subsystems with different technologies (SIP) or monolithic integra;on (SOC) Transmission of PWM/ Control/Diagnosis signals A One- chip Isolated Gate Driver with Drive- by- Microwave Technologies S. Nagai et al.,

14 Semiconductor vs Semiconductor Scaling & Device Engineering Power Si IGBT Si MOSFET SiC GaN Performance Maturity & Reliability Cost Share of Markets and Applica;ons Si MOSFET SiGe HBT GaAs/InP HEMT/HBT 14 Frequency

15 More than Moore Power J. Lutz, TU Chemnitz 2013 (Monolithic) Integrated sensing Power Circuits (on- chip or mul;- chip module, e.g. half bridge, integrated gate drivers) EC FP7 NANOTEC project, IHP RF- MEMS in MMIC tech. Heterogeneous Integra;on 15 Frequency

16 POWER SEMICONDUCTORS COMPARED: SI, SIC, GAN 16

17 Silicon- Based Power Transistors IGBT MOSFET Lateral, ver;cal, radial components Metal Isolator p(n)- Typ Si n(p)- Typ Si i- Si (n Typ Si) S1 Ch Dri_ Zone Gate Ch S2 Smart power Drain Integra;on of control logic and self- protec;on Drain Drift Zone Ch S [Schulze2011] 17

18 On- Resistance Ron = contact resistance + sheet resistance + channel resistance + JFET resistance + driv/epitaxial resistance V G V CC < 50 V V CC = 100V R K, S + R K, D V CC = 500V 100 % Metall GOX Gate R S R Ch p-typ Si n-typ Si 5 V SD R JFET R Epi Kanal i-si (n -- -Typ) Si R D 0 % [Schulze2011]

19 Infineon CoolMOS TM Technology hwp:// 19

20 Silicon- Carbide (SiC) based Power Transistors High breakdown voltage High temperature opera;on (less cooling effort) High switching speed (less and smaller passives) Si fabrica;on compa;bility JFET MOSFET IGBT [Bauer2013] 20

21 Gallium- Nitride (GaN) Based Power Semiconductors LGS = 2 µm Highest theore;cal FOM (switching speed, efficiency) Lateral HEMTs exclusively GaN/Si less costly than SiC Degree of Freedom: Bandgap engineering LG = 2 µm LGD = 15 µm Gate SiNx GaN AlGaN Sour ce GaN 2DEG Au Drain 2 nm 20 nm > 2 µm Si (111) [Ambacher2013] WG = 240 mm 21

22 Figures of Merit Goal: minimize loss = maximise efficiency Relevant device parameters breakdown voltage, leakage (gate and drain), on- resistance, threshold voltage, input- output and transfer capacitance and the gate charge Total power loss in switching component on- state loss + switching loss + junc;on capacitance loss Technology FOM 22

23 Op;mum Device Area/Size [Baliga2008] 23

24 Power Transistor FOM Maturity: Si > SiC > GaN 24 [Catrene2013]

25 Power Semiconductors versus Opera;ng Frequency Power [W] Frequency [Hz] [Ambacher2013] 25

26 Why Large Bandgap Semiconductors? SiC and GaN have 4-5 ;mes higher FOM than Si Higher efficiencies Higer breakdown voltages Higher voltage ra;ngs per stage in converters Higher switching frequencies Reduced size of passives, compact systems Higher temperature opera;on Reduced cooling effort (supply power, size of cooling system) Opera;on in high temperature environments 26

27 Power Semiconductor Industry 2500 Market share [M$] GaN technology SiC technology Semiconductor Manufacturer [Ambacher2013] 27

28 28 PROSPECTS AND CHALLENGES

29 Prospects and Challenges Challenges Higher switching frequency d/dt slope Higher opera;ng temperature Higher power per stage Stress (thermal, mechanical, chemical, electrical) Requirements (inter- dependent) EMC Efficien cy Reliabil ity Passive compo nents Therm al manag ement Packagi ng Objec;ves Lower size and weight factors Lower Cost Less Cooling effort Less Safety margins Higher Life;me 29

30 Si High maturity, but dielectric reliability issues of advanced devices High temperature opera;on Large device area Deep trenches [Schulze2011] 30

31 SiC Prospects Higher end of medium- voltage applica;ons (1200 V) Penetrate into high- voltage applica;ons, replace thyristor and IGBT (2-10 kv) for power transmission (smart grids) and engines Challenges Cost Further increase of breakdown voltages Opera;on at high temperature Reliability: gate oxides, epitaxy 31

32 GaN Prospects Medium- voltage applica;ons ( V) Penetrate into low- voltage applica;ons ( V) for switched- mode power supplies Challenges GaN on Si Fabrica;on compa;bility (ohmic contacts Au- >Al, wafer size) Normally- off - > normally- on devices Increase breakdown voltage (today > 600V) Stability, uniformity, on- resistance Traps, leakage current, kink phenomena, dynamic R on Step from lab stage to market 32

33 Challenge: Op;mum System Design Control electronics Module / Packaging Mul;- level design EMC robustness performance Power Semiconductor 33

34 Challenge: More- than- Moore in Power Electronics Control electronics Module / Packaging Power Semiconductor Func;onal integra;on density (Distributed) Current sensing (Distributed) Temperature sensing Degrada;on/ health sensing Power Circuits (on- chip or mul;- chip module, e.g. half- bridge, integrated gate drivers) 34

35 Challenge: Mul;- Level Modeling System Measurement environment System partitioning Costs Component EMC Housing PCB Power-Module Measurement environment Higher power densities Robustness Efficiency Control electronics Package Power Semiconductor Measurement environment Higher switching frequencies Degradation Thermal management 35

36 36 CONCLUSION

37 Conclusions Power semiconductors play an essen;al role in achieving the ambi;ous goals of our energy policy Wide bandgap semiconductors promise bewer efficiencies and form factors of power electronic systems such as converters, but are today less mature and reliable than state- of- the- art Si devices Distributed effects have to be taken into account in switched- mode devices with small d/dt slopes, e.g. using techniques known from microwave electronics 37

38 38 Sources [Catrene2013] Integrated power & energy efficiency, Power device technologies, simula;ons, assembly and circuit topographies enabling high energy efficiency applica;ons, Catrene Scien;fic Commiwee Working Group Integrated power & energy efficiency, hwp:// %20Sci._Comm.pdf [Baliga2008] Baliga, B. Jayant. Fundamentals of Power Semiconductor Devices. s.l. : Springer, ISBN: [Ambacher2013] Vortrag Fakultätskolloquium Universität Stuwgart, 16. April 2013 [Rohm2011] Rohm semiconductors. [Online] [Cited: 05 01, 2011.] hwp:// [Bauer2013] Anton J. Bauer, Reliability Issues in 4H- SiC Devices, Vortrag RBZ Reutlingen, [Schulze2011] Jörg Schulze, Universität Stuwgart, Vortrag Nachhal;ge Energieversorgung: Herausforderung für die Leistungselektronik, 2011 [Wicht2012] Bausteine der Leistungselektronik planen und konstruieren, Vortrag Reutlinger Innova;onstage, 2012