What is silicon carbide?

Silicon carbide (SiC) is a wide bandgap semiconductor compound formed from silicon and carbon atoms arranged in a crystalline structure. As a semiconductor material, SiC exhibits superior electrical and thermal properties compared to traditional silicon, including higher critical electric field strength, greater thermal conductivity, and enhanced switching efficiency. These characteristics make SiC particularly valuable for high-power, high-frequency, and high-temperature applications where conventional silicon semiconductors reach their performance limitations.

Where is silicon carbide used in modern electronics?

Silicon carbide semiconductors are primarily deployed in power electronics applications that demand high efficiency and superior thermal performance. The automotive industry represents the largest growth segment for SiC devices, particularly in electric vehicle powertrains where SiC-based traction inverters and onboard chargers deliver improved energy conversion efficiency and reduced system size.

Key application areas include:

(Hybrid) Electric vehicle traction inverters and DC-DC converters
Onboard charging systems for (hybrid) electric vehicles
Industrial motor drives and power supplies
Renewable energy inverters for solar and wind systems
Uninterruptible power supplies (UPS) and data center infrastructure
Railway traction systems and aerospace power electronics

SiC technology enables these applications to operate at higher switching frequencies and temperatures while maintaining lower power losses compared to silicon-based alternatives.

How does SiC compare to other semiconductor materials?

Attribute	Silicon Carbide (SiC)	Silicon (Si)	Gallium Nitride (GaN)
Attribute Bandgap	Silicon Carbide (SiC) Wide (3.3 eV)	Silicon (Si) Narrow (1.1 eV)	Gallium Nitride (GaN) Wide (3.4 eV)
Attribute Operating Temperature	Silicon Carbide (SiC) High (>200°C)	Silicon (Si) Standard (<150°C)	Gallium Nitride (GaN) Standard (<150°C)
Attribute Power Handling	Silicon Carbide (SiC) Very High	Silicon (Si) Moderate	Gallium Nitride (GaN) High
Attribute Switching Speed	Silicon Carbide (SiC) Fast	Silicon (Si) Standard	Gallium Nitride (GaN) Very Fast

Silicon carbide occupies a unique position between silicon's cost-effectiveness and gallium nitride's high-frequency performance, making it optimal for high-power applications where efficiency and thermal performance are critical.

How is Bosch positioned in silicon carbide technology?

Bosch manufactures silicon carbide power semiconductors as part of its comprehensive automotive semiconductor portfolio. Focusing on electric vehicle applications, the company develops SiC-based solutions such as SiC power MOSFETs and SiC power modules that enable traction inverters to convert DC battery power into AC motor drive signals efficiently. Bosch’s SiC power MOSFETs are offered both as bare dies and as discrete devices in a variety of standard packaging options, which allows for flexible integration: bare dies are typically utilized in high-power applications including traction inverter modules, while discrete devices are well-suited for on-board chargers and DC/DC converters.

To support the automotive industry's shift toward electrification, Bosch’s SiC technology is engineered to enhance the efficiency and performance of electric vehicle powertrains. Drawing on expertise developed through the renowned “Bosch Process,” the company has been advancing SiC semiconductor development since 2001, first introducing a prototype MOSFET in 2011. Bosch pioneered the adoption of SiC trench MOSFETs for automotive mass production, and in 2021, launched large-scale manufacturing of SiC chips on 150 mm wafers at its Reutlingen facility in Germany. Recently, Bosch completed the transition to 200 mm wafer fabrication, further increasing production capacity and efficiency.

With a global network of front- and backend semiconductor manufacturing facilities, Bosch is expanding its SiC manufacturing capabilities both in Reutlingen and at its new wafer fab in Roseville, California. This international approach strengthens supply chain resilience and improves the reliability of local market supply. Leveraging its deep automotive industry experience, Bosch delivers SiC solutions that are specifically tailored for mobility applications, positioning itself as a leading supplier of power semiconductor technology for connected, autonomous, and electric vehicles.

Frequently Asked Questions

Which role plays silicon carbide in power electronics?

Silicon carbide in power electronics refers to semiconductor devices manufactured from SiC material that control and convert electrical power in high-performance applications. SiC power devices include MOSFETs, diodes, and power modules that switch electrical current more efficiently than silicon equivalents. These devices enable power electronic systems to operate at higher voltages, frequencies, and temperatures while reducing energy losses during power conversion. SiC power electronics are essential components in electric vehicle inverters, industrial drives, and renewable energy systems where power conversion efficiency directly impacts system performance and energy consumption.

Why is SiC used in automotive applications?

SiC is used in automotive applications because it enables electric vehicle systems to achieve higher efficiency, reduced weight, and improved thermal management compared to silicon-based alternatives. Electric vehicle traction inverters built with SiC semiconductors can operate at higher switching frequencies, reducing the size of passive components like inductors and capacitors while improving power density. SiC devices also generate less heat during operation, allowing for smaller cooling systems and contributing to overall vehicle efficiency. The superior performance of SiC technology directly translates to extended driving range and faster charging capabilities in electric vehicles.

Building on these advantages, Bosch offers a holistic SiC power semiconductor portfolio that addresses the diverse needs of automotive manufacturers. This portfolio includes bare dies with various metallization options, discrete packages, and SiC power modules.

How does SiC differ from silicon?

SiC differs from silicon primarily in its crystal structure and electrical properties, which result from the incorporation of carbon atoms alongside silicon. SiC has a bandgap three times wider than silicon, allowing it to withstand higher voltages before breakdown occurs. The material also exhibits ten times higher thermal conductivity than silicon, enabling better heat dissipation and higher operating temperatures. SiC devices can switch at higher frequencies with lower switching losses, improving overall system efficiency. However, SiC manufacturing processes are more complex and costly than silicon, resulting in higher device prices that are offset by improved system-level performance.

What advantages does SiC offer at high voltage?

At high voltage, SiC offers superior blocking capability and reduced conduction losses compared to silicon semiconductors. SiC's wide bandgap allows devices to maintain stable operation at voltages exceeding 1000V while exhibiting lower leakage currents and improved reliability. High-voltage SiC devices demonstrate reduced on-resistance per unit area, enabling smaller device geometries for equivalent power handling capacity. The material's high critical electric field strength permits thinner drift regions in power devices, resulting in lower conduction losses and faster switching transitions. These advantages make SiC particularly valuable in high-voltage applications such as traction inverters, onboard chargers and DC/DC converters in electric vehicles.

Where is SiC typically used in vehicles?

SiC is typically used in electric vehicle powertrains, specifically in traction inverters that convert DC battery voltage to AC power for electric motors. Onboard charging systems represent another common application, where SiC devices enable efficient AC-to-DC power conversion for battery charging. DC-DC converters in electric vehicles also employ SiC technology to step down high-voltage battery power for auxiliary systems and low-voltage electronics. Some hybrid vehicles utilize SiC devices in their power electronics to improve fuel efficiency and reduce emissions.

Bosch offers customized SiC solutions for the mobility industry: SiC power MOSFETs and SiC power modules for various applications such as traction inverters, DC/DC converters, or onboard chargers. Bosch’s SiC MOSFETs are available as bare dies and discretes in various standard packages, or as power modules. All products are available in voltage classes 750 V, 1,200 V and 1,700 V.

Which SiC power semiconductor solutions does Bosch offer?

Bosch offers a comprehensive and customizable portfolio of SiC power semiconductor solutions for the mobility industry, covering applications such as traction inverters, DC/DC converters, and on-board chargers. Bosch’s SiC power MOSFETs are available as bare dies, discrete devices, and power modules, all designed to meet automotive-grade requirements and offered in voltage classes 750 V, 1,200 V and 1,700 V.

Bosch’s SiC bare dies provide maximum design flexibility for customers developing their own power modules. Multiple die layouts, sizes, and metallization options are available, with customized designs on request.

Bosch’s discrete SiC MOSFETs are optimized for compact and efficient power electronics, such as DC/DC converters, chargers, and smaller motor inverters. They are offered in market compatible standard packages.

Bosch designs its SiC power modules to support the entire vehicle life cycle, ensuring robustness, scalability, and long-term reliability in inverter applications. To meet different system and performance requirements, Bosch offers three complementary SiC power module concepts: Discrete SiC Line (DSL), Compact SiC Line (CSL), and Power Module 6.2 (PM6.2).

Silicon Carbide (SiC)