According with ST, SiC Power Devices will Accelerate Automotive Electrification

Silicon Carbide (SiC) is a very interesting material. If you find in nature the mineral moissanite, it will be only minute quantities in certain types of meteorite. The moissanite physical properties are very similar to these of diamond, in term of density and abrasive power. In the semiconductor industry, SiC is characterized by wide Bandgap, high breakdown voltage and high carrier drift velocity at large electric fields (saturation velocity).

These properties lead to fast response time of SiC devices and the ability for SiC MOSFET to support high-power applications better than the Silicon based equivalent devices, Insulated Gate Bipolar Transistor (IGBT). According with ST, we are talking about SiC diodes and transistors capable of operating well above the 400V range of today’s electric and hybrid drivetrains!

In Electric Vehicle (EV) and hybrids, where better electrical efficiency means greater mileage, ST’s latest silicon-carbide (SiC) technology enables auto makers to create vehicles that travel further, recharge faster, and fit better into owners’ lives. ST is among the first to present new-generation rectifiers and MOSFETs for all the vehicle’s high-voltage power modules, including the traction inverter, on-board battery charger, and auxiliary DC-DC converter.

The smaller SiC diode and transistor structures present lower internal resistance and respond more quickly than standard silicon devices, which minimize energy losses and allow designers to use higher switching frequencies for more compact designs. When using SiC MOSFET, power losses in the inverter can be reduced up to 80% at light or medium loads compared with Si IGBT. The EV and hybrids vehicle adoption in the real life will certainly benefit from innovation like SiC devices. Because SiC-based solution offers highly robust intrinsic-body diodes, eliminating the need for the freewheeling diodes necessary with IGBTs, smaller and lighter power unit with lower cooling requirements, the overall solution is smaller and cheaper.

ST is committed to support major carmakers and Tier-1 with silicon carbide technology for high power devices requirements and the company SiC devices have demonstrated superior performance and reached an advanced stage of qualification. Customers are preparing to launch new products as soon as in 2017. ST has developed the industry’s most advanced processes to fabricate SiC MOSFETs and diodes on 4-inch wafers. In order to drive down the manufacturing costs, improve the quality, and deliver the large volumes demanded by the auto industry, ST is scaling up its production of SiC MOSFETs and diodes to 6-inch wafers, and is on schedule to complete both conversions by the end of 2016.

The Automotive industry has the most stringent quality requirement (together with aeronautic) and ST has completed the qualification process for 650V SiC diodes to AEC-Q101. The company announce the qualification of the latest 650V SiC MOSFETs and 1200V SiC diodes in early 2017, when the 1200V SiC MOSFETs will be AEC-Q101 qualified by the end of 2017.

Statistics for the worldwide production of vehicles (car and commercial) is 90 million in 2015. If the adoption for EV and hybrids is growing as it did last year with 60% year to year growth, the prediction calling for 35% of EV and hybrids to be produced by 2040 sounds realistic. We can easily evaluate the impact of such production level in our day to day life, especially for those leaving in a large city surrounded by car pollution. 35% of 100 million vehicles (at that time) make 35 million. If we evaluate an average mileage of 12,000 km (*) and an average oil consumption of 8 liters by 100 km, we come to a total of 35 million x 1000 liters, or 35 billion liters of oil which will NOT be consumed! At least not being consumed in a car motor, generating direct pollution…

* To US readers: sorry to use MKSI or International Unit System…

That’s why technologies like silicon carbide are so important, becoming the enablers for changes in the human being behavior. Thanks to wide bandgap SiC devices, offering lower energy losses, supporting higher voltages and operating faster than Silicon based IGBT MOSFETs.

From Eric Esteve from IPNEST