Bosch Enters SiC Production Everything From a Single Source

Harald Kröger, Bosch: "Silicon carbide semiconductors bring more power to electric drives. For motorists, this means a 6 percent increase in range."

As the world's first Tier 1, Bosch will manufacture SiC power semiconductors for its own needs in the future. The company is currently working on setting up a pilot line for 150 mm SiC wafers in Reutlingen.

This would make Bosch the third largest manufacturer of SiC power semiconductors in Europe after Infineon Technologies and STMicroelectronics. The first customers will receive samples as early as next year. "Silicon carbide semiconductors will change electromobility in the long term," assures Bosch Managing Director Harald Kröger.

With this step, Bosch is making itself independent of suppliers such as Infineon Technologies, Cree, STMicroelectronics, and Rohm Semiconductor, thereby increasing its local added value. Bosch customers will in future receive complete SiC-based products from a single source. One example of this is the eaxis developed by Bosch, a product that combines electric motor, power electronics, and gears into a compact unit.

The decision to enter SiC power semiconductor manufacturing was made at Bosch last year, after the company had already spent several years working on SiC in its central research and advance development department. Bosch remains silent about the exact number of its patents in the SiC field. However, the Stuttgart-based company, together with other semiconductor manufacturers, is working on new processes that will make the production of SiC power semiconductors even more efficient.

The decisive factor for the company's entry into SiC production was probably the realization that Bosch's knowledge of SiC power semiconductors, supported by its own production, offers the opportunity to fully exploit the specific advantages of SiC in its complete systems. Bosch sees it as its unique selling point to be the only automotive supplier that masters both semiconductors and complete systems in cars. Against this background, the company sees itself in a position to supply semiconductor solutions to problems that other semiconductor manufacturers have not yet seen.

According to Bosch, raising and financing this potential is not insignificant, but worthwhile in the longer term. According to Bosch, the company has so far invested a three-digit million sum in the establishment of a SiC production facility in Reutlingen. Upon request, Bosch did not want to answer from whom the company procures its SiC wafers.

Due to their low power dissipation, SiC power semiconductors are particularly suitable for applications in which particularly high energy efficiency is required. The SiC power semiconductors show their greatest advantages at high temperatures and high operating voltages, such as in the electric drive train of a vehicle. An application such as the eaxis mentioned above with a scalable output of 50 to 300 kW should therefore be the first choice when it comes to in-house use of the SiC power semiconductors produced in Reutlingen. In addition to applications such as the eaxis, they will also be used in stand-alone power electronics.

In view of the fact that Bosch key customers are to receive the first samples of Bosch SiC power semiconductors next year, it is not expected that electric vehicles with the corresponding Bosch SiC power semiconductors will be on the road before 2022/23. At this point, Reutlingen may also be considering whether Bosch should migrate from 6-inch to 8-inch SiC wafers in the future. SiC pioneer Cree recently announced that he would start ramping up production on 200 mm wafers from 2022 in his newly built SiC power semiconductor plant in Marcy, New York.