5 June 2012 SiC drives material innovation for high-power electronics
Due to its superior thermal and electrical properties, the wide-bandgap material silicon carbide (SiC) has emerged as a key enabling material that has the potential to displace silicon-based insulated-gate bipolar transistors (IGBTs), metal oxide semiconductor field-effect transistors (MOSFETs), diodes and rectifiers (specifically in high-power electronics for applications in photovoltaic panels, hybrid/electric cars, high-power industrial drives, motor drives, smart grids and power utilities), according to Frost & Sullivan’s report ‘Silicon Carbide Electronics —Technology Market Penetration and Roadmapping’.
The report finds that SiC-based power electronics are well positioned to meet some of the key performance criteria, such as decreased overall system costs and enhanced system efficiency for emerging applications such as hybrid vehicles and inverters for solar energy.
“Silicon carbide electronics exhibit superior thermal resistance, low conductivity losses and higher material strength than silicon," says Avinash Bhaskar, industry analyst with Frost & Sullivan’s Technical Insights research group. “Thus, silicon carbide-based power electronics such as diodes and transistors can potentially reduce the size and also switch losses in power systems by 50%,” he adds.
Encouraged by their superior material properties, major automotive manufacturers involved in developing hybrid and electric vehicles are currently testing SiC-based MOSFETs and other transistors as a viable alternative to silicon-based transistors, particularly for under-the-hood applications where the operating conditions are challenging.
“Defense agencies are also driving the research on using silicon carbide for developing power electronic devices,” says Technical Insights industry manager Kasthuri Jagadeesan. “A commercial volume market in the renewable sector, industrial sector and automotive sector could present a big market opportunity for silicon carbide power electronics.”
The future of SiC will lie in developing reliable transistors such as MOSFETs and bipolar junction transistors. While SiC-based diodes have made their way into a number of applications, end-users are truly interested in a reliable SiC-based MOSFET that can challenge the dominance of silicon-based IGBTs.
Hybrid electric cars will greatly benefit from having SiC MOSFETS under the hood, as SiC has a better thermal resistance than silicon-based IGBTs, notes the report. This will reduce the overall system cost in electric cars, as adopting SiC devices will lead to eliminating the use of heat sinks and other cooling devices.
“However, silicon carbide material defects, higher cost of manufacturing wafers and packaging issues could hamper the growth of silicon carbide power electronics,” cautions Bhaskar. "The research efforts in developing reliable silicon carbide-based transistors in the higher-power realm have been sluggish, slowing down the time to market.”
Strong collaborations and alliances along with increased investments will accelerate developments in the SiC power electronics technology space, reckons the market research firm. Several companies have started sampling SiC MOSFETs and DMOSFETs, which will aid the rapid deployment of SiC power electronics in the commercial market, it concludes.
