South Korea has taken a major leap forward in sustainable high-tech manufacturing. A research team led by Dr. Joon-seok Ko at the Energy Storage Research Center of the Korea Institute of Machinery and Materials (KIMM) has successfully developed a turbo-Brayton cryogenic cooling system capable of delivering 15 kilowatts (kW) of cooling performance at temperatures below $-120^circtext{C}$.

Overcoming Limitations of Traditional Chiller Systems

Advanced, highly integrated semiconductor manufacturing processes require ultra-low-temperature chillers—often reaching around $-100^circtext{C}$—to effectively dissipate intense heat. However, conventional vapor-compression chillers frequently rely on refrigerants with high global warming potentials (GWP) and face structural limitations when trying to expand cooling capacity.

To solve this, the KIMM research team adopted a turbo-Brayton cycle, which harnesses the cooling effect produced by compressing and expanding nitrogen gas. Because nitrogen boasts a GWP of zero, it acts as an environmentally safe and harmless medium. Furthermore, the team designed the cooling system to operate at pressures below 10 atmospheres, significantly enhancing overall operational safety.

Innovation in Core Components

At the heart of the system is a specialized turbomachinery utilizing magnetic bearings to support the rotating shaft without the need for lubricating oil. Operating at ultra-high speeds of 60,000 revolutions per minute (rpm), conventional oil-lubricated systems risk freezing and subsequent failure under extreme cryogenic conditions.

By independently developing oil-free turbomachinery, the team eliminated this vulnerability while enabling flexible control over both temperature and cooling capacity. The compact, simplified structural design also minimizes the physical footprint required in industrial settings.

Proven Performance and Commercial Outlook

During self-performance tests, the newly developed chiller plummeted to below $-120^circtext{C}$ within 30 minutes of startup and successfully achieved its target load capacity of 15 kW in under 60 minutes. Under rated operating conditions, the system recorded a power consumption of 90 kW and a coefficient of performance (COP) of 0.167. This milestone marks South Korea's first successful development and operational validation of a commercial-grade, large-capacity turbo-Brayton cryogenic chiller.

This achievement builds upon the team's 2004 breakthrough—where they demonstrated 10 kW cooling performance at $-100^circtext{C}$—and elevates the technology to a robust industrial scale. It is expected to directly cater to semiconductor manufacturing facilities urgently seeking hyper-integrated fabrication processes.

The technology has already been transferred to Chago Engineering, a dedicated semiconductor chiller manufacturer, with a commercial product launch targeted for next year. Looking ahead, KIMM’s Energy Storage Research Center plans to advance its cooling capabilities down to $-269^circtext{C}$, expanding applications into future-oriented sectors such as superconductivity, aerospace, hydrogen energy, quantum computing, and nuclear fusion.

"We will continue to develop versatile industrial cryogenic cooling technologies that can be deployed not only in semiconductor manufacturing but across a wide array of promising future industries," stated Dr. Joon-seok Ko.

[ⓒ Global Economic Times. 무단전재-재배포 금지]