Wolfspeed, a pioneer in the SiC power semiconductor market, filed for Chapter 11 bankruptcy protection in June 2025. The company reached a restructuring support agreement with major creditors that included approximately $4.6 billion in debt reduction, and announced the successful completion of its financial restructuring in October of that year — yet the entire episode threw the risks of single-supplier dependence in SiC procurement into sharp relief. Renesas Electronics had provided a $2 billion deposit under its SiC wafer supply agreement with Wolfspeed, and the bankruptcy filing resulted in a loss of approximately ¥250 billion.
Key Players in the SiC Power Semiconductor Market
The top four SiC power semiconductor vendors by revenue — Infineon, STMicroelectronics, ROHM, and Wolfspeed — have each been meeting expanding demand with year-on-year growth rates of 29–42%. Additional alternative suppliers include onsemi, Fuji Electric, Mitsubishi Electric, and Chinese manufacturers. The following sections compare the characteristics of the major suppliers beyond Wolfspeed.
Infineon CoolSiC
Infineon CoolSiC MOSFETs reduce switching losses by approximately 80% and conduction losses by up to 50% compared with Si-based IGBTs. The latest G2 generation cuts losses a further 5–20% over its predecessor, reduces thermal resistance by 12%, and improves heat dissipation capability by 14%. Against competitors, CoolSiC achieves power loss reductions of 4–17% in 1200 V devices and 13–64% in 650 V devices, with a particularly pronounced advantage in the lower voltage range. With its main manufacturing base in Dresden, Europe, and a strong track record in both automotive and industrial markets, Infineon currently ranks among the suppliers offering the highest procurement stability.
onsemi EliteSiC
onsemi EliteSiC is characterized by high efficiency through low power loss and high reliability. The EliteSiC M3e MOSFET reduces conduction losses by 30% and switching losses by up to 50%. onsemi offers a complete portfolio spanning SiC MOSFETs, diodes, and modules from 650 V to 1700 V, enabling straightforward adoption without dependence on a specific voltage rating or application. A growing body of EV traction inverter design wins supports its track record, and the T2PAK top-cool package delivers superior thermal performance that broadens design flexibility.
ROHM — Differentiated by Short-Circuit Withstand Time
ROHM's fourth-generation SiC MOSFETs achieve both low on-resistance (Ron) and high short-circuit withstand time (SCWT) through a proprietary device structure. While SiC inherently exhibits lower SCWT than Si, ROHM's fourth-generation technology improves this trade-off, providing greater margin in protection circuit design. The company's well-developed domestic technical support infrastructure — including Japanese-language assistance and evaluation kit availability — represents a tangible advantage for Japanese manufacturers during the design and evaluation phases.
Mitsubishi Electric and Fuji Electric — Domestic Supplier Positioning
Mitsubishi Electric has developed technology that introduces a p-type protection layer into trench-type SiC MOSFETs, significantly improving SCWT. Its strengths lie in domestic manufacturing that minimizes geopolitical risk and in the ease of information sharing through established business relationships. Fuji Electric is also expanding its SiC device lineup for automotive and industrial equipment, with strong compatibility with Japan-based design and mass-production workflows.
Evaluating Chinese Manufacturers
Chinese SiC manufacturers began volume production of 8-inch wafers in 2024 and demonstrate clear price competitiveness. Wafer quality has improved rapidly in recent years and is drawing attention at international conferences. That said, in high-value automotive and industrial applications, European, U.S., and Japanese manufacturers retain an advantage through quality certifications such as AEC-Q101. When considering adoption, a comprehensive evaluation covering geopolitical risk, the outlook for long-term quality certification, and supply continuity — not price competitiveness alone — is essential.
Supplier Selection Criteria
| Criterion | Priority | Key Verification Points |
|---|---|---|
| On-resistance (RDS(on)) reduction rate | High | Request competitive comparison data under equivalent conditions |
| Short-circuit withstand time (SCWT) | High | Must be verified at actual operating voltage and temperature |
| Automotive qualification (AEC-Q101) | Mandatory for automotive | Verify per specific part number, not across the entire lineup |
| 8-inch transition roadmap | Medium- to long-term | Confirm supply capacity plans for 2025–2028 |
| Geographic diversity of manufacturing sites | High | Assess single-site concentration risk |
| Technical support infrastructure | Medium | Confirm Japanese-language support and evaluation kit availability |
Summary
For those prioritizing reliability and supply stability, Infineon CoolSiC G2 and onsemi EliteSiC M3e are the leading candidates at this time. ROHM warrants consideration for protection circuit designs where SCWT is paramount. When domestic manufacturing and support are the priority, deepening relationships with Mitsubishi Electric or Fuji Electric merits evaluation. Building a multi-supplier model and establishing a long-term roadmap that captures cost reductions after the 8-inch transition will define the competitive conditions for design and procurement going forward.