Revealed the True Nature of the 'Killer Defect' Undermining AI Semiconductors and Electric Vehicles [Reading Science]

KERI Becomes First in the World to Identify Trapezoidal Defect Structure in SiC Power Semiconductors
Revealing the Cause of Yield Loss... Laying the Foundation for Mass Production of High-Quality Wafers

The true nature of a representative 'killer defect' that lowers the yield of silicon carbide (SiC) power semiconductors, which have gained attention as key components for artificial intelligence (AI) data centers and electric vehicles, has been revealed for the first time in the world. With the identification of the mechanism behind the creation of fatal defects occurring during semiconductor production, it is evaluated that a foundation has been established for improving the quality and productivity of next-generation power semiconductors.

The Korea Electrotechnology Research Institute (KERI) announced on June 21 that a research team led by Dr. Namoonkyung at the Next-Generation Semiconductor Research Center, in collaboration with Professor Hong Soongoo's team at Chungnam National University and Horiba STEK Korea, has, for the first time in the world, identified the internal structure and cause of the occurrence of the Trapezoidal Defect (TZD) found during the SiC power semiconductor manufacturing process.

Advanced national infrastructure used in the study identifying trapezoidal defects in the SiC power semiconductor process. (Clockwise from top left) MiPLATO-SiC (Horiba STEK Korea), Scanning Transmission Electron Microscope (Gumi Electronics & Information Technology Institute), Nurion Supercomputer (Korea Institute of Science and Technology Information), Synchrotron Accelerator (Pohang Accelerator Laboratory). Provided by KERI

SiC power semiconductors are considered essential next-generation semiconductors for electric vehicles, renewable energy, and AI data centers, as they can withstand higher voltages and high-temperature environments compared to conventional silicon power semiconductors.

However, crystal structure defects that occur during the manufacturing process have been pointed out as a major factor that significantly reduces yield. In particular, the trapezoidal defect, which can be up to 1 mm in length, has been known as a representative 'killer defect' that disrupts current flow and damages chips. However, its exact structure and formation process had not been identified until now.

Full Utilization of National Advanced Infrastructure to Track the Cause

The research team focused on the unique stripe patterns found inside the trapezoidal defect. By integrating eight analytical techniques—including photoluminescence mapping, spectrum analysis, atomic-level interpretation, and density functional theory (DFT) calculations—they precisely analyzed the defect structure.

Additionally, the team leveraged national cutting-edge research infrastructure, including the high-resolution scanning transmission electron microscope (HR-STEM) at the Gumi Electronics & Information Technology Institute, the Nurion supercomputer at the Korea Institute of Science and Technology Information (KISTI), and the Pohang Synchrotron Accelerator, conducting research for over a year.

As a result, the team confirmed that there are complex defect structures comprising up to 32 layers inside the trapezoidal defect. They also discovered that the defect propagates along the epitaxial layer during the semiconductor manufacturing process and expands by changing its own shape.

KERI research results were presented at ICSCRM 2025, an international academic conference specializing in SiC. Photo by KERI

This research is expected to provide important clues for controlling defects in the SiC power semiconductor production process and for securing technology to mass-produce flawless wafers.

Dr. Namoonkyung of KERI stated, "We have, for the first time in the world, revealed at the atomic level the complex internal structure and evolution process of the massive trapezoidal defect that has degraded power semiconductor performance. This will serve as a technological foundation for the mass production of high-quality SiC power semiconductors."

The results of this research were published in 'Acta Materialia,' the most prestigious academic journal in the field of metals and inorganic materials. While it usually takes more than four months for a paper to be reviewed and accepted, this study received publication approval just two months after submission, reflecting the significance of the research findings.

This content was produced with the assistance of AI translation services.