KERI develops SiC defect analysis and evaluation technology.
Early observation of invisible SiC crystal defects
Developing equipment with Etamax, half the price of Japanese equipment


Silicon carbide (SiC) has recently been gaining attention as a power semiconductor material due to its superior durability, versatility, and efficiency compared to silicon (Si). However, SiC has invisible internal crystal defects (dislocations) that can reduce the performance of semiconductor devices.

The Korea Electrotechnology Research Institute (KERI) Power Semiconductor Research Center's Dr. Bang Wook and Dr. Na Moon-kyung's team announced on the 8th that they have developed a technology to analyze and evaluate crystal defects in SiC materials at an early stage.

Crystal defects are complex and difficult to identify. They can degrade the characteristics of semiconductor devices from the very beginning of their operation, and in some cases, their characteristics can change during use, causing problems. If a problem occurs in SiC power semiconductors in power grid equipment or electric vehicles on the road, it could result in serious damage to life and property. This is why analytical technology is crucial.

Defects in SiC materials are invisible, and the material itself is hard, making observation difficult. Currently, the technology for SiC material inspection equipment is so complex and the barriers to entry are high, with Japan holding over 80% of the global market. Due to the high equipment prices, performance testing in Korea is limited to a limited number of wafer samples. Accordingly, the research team developed a technology for detecting defects in SiC materials using the photoluminescence (PL) phenomenon for the first time in Korea.

PL analysis analyzes the phenomenon in which excited electrons emit light of a specific wavelength as they return to their original positions. This involves sending ultraviolet (UV) energy to SiC material and analyzing the specific wavelengths emitted by the electrons to determine whether they are normal or not.

SiC is an indirect semiconductor material with low PL emission efficiency, making signal detection difficult. The research team, in collaboration with Etamax Co., Ltd., a company specializing in optical inspection equipment, developed a "SiC material defect analysis device for power semiconductors" that reduces PL loss.

Unlike Japanese products that detect surface and internal defects by selecting two different wavelengths of light depending on the inspection target and evaluation items, the newly developed equipment uses a single laser wavelength to detect various internal defects without destroying the SiC material. The research team stated, "The equipment's performance is equal to or better than that of the Japanese equipment," and added, "We expect to be able to supply it at half the price of the Japanese product, which costs approximately 1.4 billion won."

Dr. Moon-Kyung Na of KERI stated, "Through continued research, we will expand the evaluation scope to include broadband semiconductor materials such as diamond, and strive to diversify and refine our analysis techniques." The research team has completed a patent application for the technology and plans to continue working with Etamax to upgrade the equipment and accelerate commercialization.

Meanwhile, market research firm IHS Markit forecasted that the SiC power semiconductor market size would grow by an average of 32% annually from approximately $700 million (approximately KRW 780 billion) in 2020 to approximately $10 billion (approximately KRW 11.14 trillion) in 2030.