News Article
Energy-efficient SiC power switches
Acreo to collaborate with DENSO to develop energy-efficient SiC power switches for non-automotive applications
Acreo AB signed an agreement with DENSO Corporation to promote a highly efficient, normally-off power switch technology, developed at DENSO, and evaluate it in non-automotive applications. The switches will be fabricated using the wide band gap semiconductor Silicon Carbide (SiC) and the design is based on the innovative material and processing technology available on both sides.
At first, a power switch with an operating voltage of 1200 V and a current rating of 50 A is designed and fabricated. The switching device of choice is a normally-off junction field effect transistor (JFET) processed with epitaxial material technology. DENSO is developing high quality SiC wafer material, power switches and module technology for over 10 years. The all epitaxial JFET concept was designed and successfully tested at DENSO for current ratings over 50 A. The epitaxial material was supplied by Acreo. Acreo has more than 15 years experience in developing epitaxial growth technologies and innovative device processes for SiC. For the 50 A rated devices, the JFET process technology will be established at Acreo's SiC process line at the ElectrumLab in Kista and device fabrication will start from autumn 2010. It is planned that packaged JFET devices are ready for system evaluation demonstrator circuits in the beginning of 2011. The targeted applications are dc-dc converters, battery chargers, and photovoltaic systems. This technology can be considered for robust high temperature automotive applications in the future.
The collaboration with DENSO for the fabrication of normally-off SiC-JFET power devices is the result of joint research activities regarding SiC material technology for more than five years. The new agreement includes the transfer of the DENSO JFET technology to Acreo and is supported by the Swedish Governmental Agency for Innovation Systems (VINNOVA) and the Invest in Sweden Agency (ISA), Japan.
By combining both side's competence and long experience in SiC R&D, material technology, and knowledge in power device design and processing, the fabrication of high performance and efficient normally-off SiC-JFET devices will be possible. These SiC-JFETs should contribute to revolutionize power electronics and lead to smaller, lighter, and more-efficient power systems. Compared to conventional Si technology, a reduction in size and weight by at least factor 6 is in reach with no compromise in energy conversion efficiency.
"The agreement takes our cooperation into a new important phase, enabling us to test the new technology in real, demanding applications", says Mårten Armgarth, CEO at Acreo. The next generation of power devices are herewith directly accessible for Swedish system companies.
"It's time to explore the energy-efficient SiC power device potential non-automotive applications. This collaboration will help in discovering new business frontiers in Europe", says Hikaru Sugi, DENSO's senior managing director overseeing Engineering Research & Development Center.
