Volvo Technology Transfer (VTT) is investing SEK 2 million (US$295,000) in TranSiC AB, a developer of developer of energy-efficient power transistors in silicon carbide. The investment was part of a SEK 4 million total round, which was co-led by Midroc New Technology AB of Sweden.
Silicon carbide (SiC) offers a range of benefits compared to conventional all-silicon semiconductors: smaller size, drastically reduced switching losses, low leakage, higher switching frequencies, and the ability to operate at much higher temperatures.
One problem with electric hybrid vehicles is that they often require cooling of both the motor and the electronics. With silicon carbide, the heat losses are small so perhaps no cooling will be needed.—Anders Kroon, head of hybrid technology at Volvo Powertrain
The potential for using SiC to make the vehicle’s electronics far smaller and much more compact would lead to making the entire vehicle lighter and less expensive. A current MSc thesis at Volvo Powertrain is studying silicon carbide and its applications in hybrid vehicles.
Target specifications for the TranSiC BitSic power bipolar junction transistors (BJTs) are:
- Room temperature VCESAT less than 1 V (at RT);
- 1,200 V and 6 A device rating;
- TO220 device package capable of 175 ºC or single die capable of 250 ºC;
- Storage time delay less than 100 ns;
- Rise- and fall-times less than 50 ns and nearly temperature independent switching; and
- Wide RBSOA, short-circuit capability and excellent immunity to cosmic rays.
This investment will enable us to bring to our customers power bipolar junction transistors (BJTs) in silicon carbide (SiC). The first transistors will be rated for 1200 V and offer advantages in terms of low power losses, fast switching and excellent ruggedness. We are also planning for a package technology that can withstand temperatures up to 225º C.—Bo Hammarlund, CEO TranSiC AB