This document discusses the potential for silicon carbide (SiC) in power electronics applications. SiC has a wide bandgap that allows transistors to operate at higher voltages, temperatures, and frequencies than silicon. Its main advantages are higher power density, lower losses, smaller components, and reliability at elevated temperatures. The document outlines SiC applications in renewable energy systems, motor drives, and other industrial uses. However, a lack of suitable substrates currently limits mass production of SiC power devices.

1. SIC- A NEW ERA IN
POWER
ELECTRONICS
Prepared By:
Krunal P. Siddhapathak (10bec097)

2. OUTLINE
 Introduction
 Why used in high temperature application?
 Advantages
 Applications
 Why SiC is not used?
 Conclusion

3. INTRODUCTION
 Silicon Carbide (SiC) is a very hard semiconductor material
 SiC has been used in abrasive products such as grinding
wheels for more than one hundred years.
 Today, high quality monocrystal SiC substrates with
diameters up to 100 mm are commercially available and their
main application is light-emitting diodes.
 SiC is becoming more widely used in power applications
such as power factor control in power supplies.
 SiC has a wide band gap of 3.2 eV which is almost three times
the band gap of Si (1.1 eV).
 This quality enables semiconductor devices made out of this
material to maintain a satisfactory function even at higher
temperatures.

4. INTRODUCTION(CONTD.)
 Silicon Carbide’s wide band gap makes it possible to produce
power transistors that block high voltages and have low series
resistance, leading to low conduction losses.
 Thanks to the low conduction losses, the chip size can
be reduced and it is possible to switch the transistors with low
switching losses.
 The high band gap also enables power transistors to switch
high voltage and current at high temperatures.
 In conclusion, SiC's power transistors are electrically
robust, with excellent short circuit capabilities.

5. Fig 1 Schematic of hetrojunction SiC
transistor

6. WHY SIC IS USED IN HIGH
TEMPERATURE APPLICATIONS?
 The variation in current gain
versus temperature is shown
in figure
 As shown in figure there is
only 10 to 15% change in
current gain when
temperature changes from
300K to 400K.
 While normal transistor fail
at elevated temperature due
to significance increase in
current gain.

7. ADVANTAGES
 Higher Power Density
 Through higher switching frequency at same or lower
losses, enabling the use of smaller inductors, heat-sink and
capacitors
 Increase output power while maintaining system form
factor
 Lower System Cost
 Through lower losses and higher power density, smaller
cooling and increased power output for the same hardware
 Offer productivity improvement.

8. ADVANTAGES(CONTD.)
 Key SiC Features
 Wide band gap (3.2 eV, 3x Si)
 High break down field (2.4 MV/cm, 10x Si)
 High thermal conductivity (4 W/cm K, 3x Si)
 High temperature stability.
 Fast Switching
 Approximately 20 ns for turn-on and turn-off.
 Switching behaviour is not temperature dependant.
 No current tailing for SiC BJT.

9. ADVANTAGES(CONTD.)
 Robust and Reliable
 Normally OFF device.
 Highest rated operating temperature =175 C
 Positive temperature coefficient (Ron)
 No Secondary breakdown for SiC BJT
 Low leakage current.
 Short circuit resistance.
 No SiO2 gate oxide reliability issue.

10. APPLICATIONS
 High Efficiency Applications such as renewable
energy, industrial systems and mobile power all require high
efficiency, small size and light weight.
 Fairchild is developing a series of device solutions that will
offer the industry’s highest efficiency compared to any other
transistors available today.
 These components also eliminate many of the size, weight and
temperature trade-offs associated with efficiency gains in
silicon devices.
 High Temperature The ability for power semiconductors to
provide reliable operation at high temperatures.

11. APPLICATIONS(CONTD.)
 Lower Losses, Faster Switching, Higher Power
Density
 Solar inverters
 Welding systems
 Mobile power
 DC-DC converters
 DC-AC inverters
 PFC input stages
 Motor drives

12. APPLICATIONS(CONTD.)
 Higher Operating Temperatures
 High temp DC converters
 High temp actuator controls
 High temp motor drivers
 Motor and turbine controls
 Surveillance

13. WHY SILICON CARBIDE DEVICES
ARE NOT AVAILABLE?
 Lack of suitable substrate for the industrial scale
fabrication of power semiconductor devices.
 SiC can not be melted under controllable conditions
 It changes its state directly from solid to gaseous.

14. CONCLUSION
 Silicon carbide transistors has several advantages over silicon
transistor like fast switching, high power reliability, high
temperature stability etc.
 Main disadvantages is that lack of substrate in fabrication of
power semiconductor devices.

15. REFERENCES
 B.J.Baliga, “The Future of Power Semiconductor Device
Technology”, Proceedings of the IEEE, June
2001,Vol.89, No.6, pp.822-832
 Orellana Alavaro, Piepenbreier Bernhard, “Fast Gate Drive
for SiC-JFET using a Conventional Driver for MOSFETs and
Additional Protections,” The 30th annual Conference of the
IEEE Industrial Electronics Society, pp. 938-943.