Silicon Carbide (SiC) Technology at A*STAR IME

The foundation of high-performing SiC power devices lies in defect-free epitaxial layers. Even minor defects such as basal plane dislocations (BPDs) and micropipes can severely impact device reliability. IME focuses on refining epitaxial growth processes to achieve superior uniformity and reduce defect densities, ensuring high-quality substrates for advanced applications such as power electronics and high-power.

• Collaborations:

  • Soitec: Joint development of 200mm SiC substrates using Soitec’s Smart Cut™ technology, integrated with IME’s pilot production expertise, enhances MOSFET processes for these substrates for device yield and performance. By developing advanced epitaxy solutions, the collaboration aims to create a benchmark for SiC MOSFET devices, driving innovation in the SiC ecosystem and supporting high-volume manufacturing in the future.

  • LPE SpA (An ASM Company): Partnership on the development of high-quality 200mm SiC epitaxy processes and optimizing epitaxial growth rates and material properties using LPE’s cutting-edge CVD (chemical vapor deposition) reactor technology. In this collaboration, the goal is to reduce killer defect densities while optimizing material properties, ultimately contributing to the development of next-generation SiC devices with superior performance and reliability.​

IME addresses the entire SiC MOSFET value chain, from conceptual design to fabrication and rigorous testing.

• Design and Simulation: Leveraging TCAD (Technology Computer-Aided Design) simulations to model next-generation MOSFETs that deliver higher switching speeds, better energy efficiency, and superior thermal management. With the industry's transition to higher current ratings and larger chip areas, improving on-state resistance is crucial. We are exploring novel gate dielectric materials and unique processing methods to reduce this resistance, pushing the boundaries of SiC power electronics for applications such as electric vehicles and renewable energy systems.

• Fabrication: A dedicated 200mm SiC line supports pilot-scale manufacturing, accelerating the development cycle from prototype to production. We are pioneering approaches to reduce yield-killer defects in SiC epilayers, such as BPDs (basal plane dislocations), during fast growth epitaxy, which are critical as the industry moves towards larger chip areas with lower on-state resistance.

• Testing: Automated and semi-automated integrated solutions to rigorously validate static and dynamic performance of SiC devices’ reliability under extreme conditions, ensuring innovation aligns with industry standards. By bridging simulation, fabrication, and testing, we ensure that SiC MOSFETs are not only innovative but also meet the stringent demands of the power electronics industry, driving the development of high-efficiency, next-generation SiC power electronics.

The gate dielectric and MOS interface play pivotal roles in optimizing device performance by minimizing leakage currents, enhancing breakdown strength, and stabilizing threshold voltages for advancing the performance and reliability of SiC-based power devices.

• Research Focus:

  • Refining traditional and novel dielectric materials.

  • Address defects at the SiC/dielectric interface to boost channel mobility and reduce charge traps, hence reducing leakage currents, improving threshold voltage stability, and boosting overall device efficiency for high-performance applications.

• Key Partnerships:

  • centrotherm: Collaboration on advanced diffusion and annealing tools for optimized trench and gate oxide formation in 200mm SiC devices. This collaboration is enhancing SiC device performance through optimized trench and gate oxide formation. This collaboration explicitly targets applications such as electric vehicles and power grids.

• Material characterization tools:

  • Through these efforts and our state-of-the-art material characterization tools, we are supporting the development of next-generation SiC devices with superior reliability and efficiency. This research is crucial for meeting the increasing demands of industries like electric vehicles and renewable energy systems, pushing the boundaries of SiC device capabilities.

Reliable ohmic and Schottky contacts are essential for high-efficiency SiC devices to reduce power losses and enhance device efficiency.

• Focus Areas:

  • Reducing contact resistance for improved current flow in ohmic contacts. Ohmic contacts are crucial for establishing low-resistance connections between metal and semiconductors, ensuring efficient current flow.

  • Enhancing rectification performance and reducing leakage currents in Schottky contacts.

  • Improve the electrical performance and efficiency of SiC devices by addressing critical contact types and innovating new materials and processing techniques to meet demands for high-power and high-frequency applications.

Packaging is critical for thermal management, electrical insulation, and mechanical stability in high-power SiC devices.

• Key Innovations:

  • Development of advanced power module designs capable of withstanding junction temperatures up to 200°C.

  • Proprietary interconnection techniques and cooling systems, such as double-sided liquid cooling, for next-gen applications like 6-in-1 modules.

• Collaborations:

  • Toray Industries, Inc.: Joint efforts to develop next-generation power module packaging materials to improve the efficiency and reliability of SiC power modules that are crucial for high-performance applications like electric vehicles and renewable energy systems.