Advanced power semiconductors block radiation damage and lead space industry development!

The research team led by Dr. Jae Hwa Seo at Advanced Semiconductor Research Center of KERI has developed technology to evaluate radiation resistance and secure reliability of silicon carbide (SiC) power semiconductor devices in space environment.

Power semiconductors are essential components of electrical and electronic devices, regulating current flow and enabling power conversion, much like muscles control movement in the human body. While silicon (Si) is currently the most widely used material for power semiconductors in electric vehicles and space environments, wide bandgap (WBG) power semiconductors¹⁾ such as silicon carbide (SiC) and diamond, which offer higher performance and durability, are gaining significant attention as advanced alternatives.
^{1) Wide Band Gap power semiconductor: Power semiconductors composed of compound elements of two or more types, rather than single materials like silicon (Si). Silicon carbide (SiC) and gallium nitride (GaN) power semiconductors are representative examples. WBG power semiconductors offer significantly better performance due to their larger band gap compared to conventional power semiconductors. The most prominent example, SiC power semiconductors, can withstand voltages 10 times higher than silicon power semiconductors, operate at temperatures of hundreds of degrees Celsius, and consume less power, thereby increasing energy efficiency. When applied to electric vehicles, SiC power semiconductors can provide remarkable benefits, with up to 10% improvement in power efficiency compared to silicon.}

Space radiation is considered a major cause of severe degradation in the electrical characteristics of power semiconductors installed in aircraft, exploration vehicles (rovers), and satellites. While radiation effect research is actively conducted in the United States and Europe, Korea's efforts have primarily focused on the quantitative analysis of radiation resistance in silicon power semiconductors, with limited research outcomes.

KERI has successfully developed technology to effectively evaluate the radiation resistance of SiC power semiconductors through Korea's first high-energy space environment simulation. The most crucial aspect was creating an extreme space radiation experimental environment. Space radiation comprises particles of varying energy levels, with protons making up 80–90% of the total composition. Dr. Seo's team utilized high-energy protons (100 MeV) from the accelerator facility at the Korea Atomic Energy Research Institute, and collaborated with the team led by Professor Yoon Young-jun from Andong National University, experts in the field, to implement precise radiation exposure conditions.

Under these space environment conditions, KERI systematically analyzed the effects on domestically developed SiC power semiconductors, including voltage changes, increased leakage current due to exposure, and lattice damage. Using the accumulated data, the team formulated design criteria to ensure the long-term reliability of SiC power semiconductors for space applications. The research excellence was recognized with recent publication in Radiation Physics and Chemistry, a top-tier SCI journal (top 8.7%) in NUCLEAR SCIENCE & TECHNOLOGY.

Dr. Jae Hwa Seo of KERI stated, "Setting various radiation effect parameters and testing core components in similarly simulated environments is considered a key space industry technology worldwide," adding that "this technology will be applied across various fields including aerospace, medical radiation equipment, nuclear power plants, radiation waste treatment facilities, and military/defense electronics."

The research team plans to expand the technology's scope by pursuing reliability evaluations of SiC power semiconductors under ultra-high energy (over 200MeV) radiation conditions and developing advanced radiation-resistant power semiconductors. Additionally, they are conducting research on future power semiconductors using diamond, which has the best semiconductor properties on Earth, in collaboration with Gyeongnam Province and Japanese company 'Orbray'. Their goal is to contribute to Korea's development in high-value-added aerospace industries.

Meanwhile, KERI is a government-funded research institution under the National Research Council of Science & Technology, Ministry of Science and ICT. This research was conducted as part of KERI's basic project (Development of Core Technologies for High-temperature, High-frequency, High-efficiency (3 High) Power Control Modules). <KERI>