Master’s students Hyunjae Shin (Graduate School of Semiconductor Technology) and Jihwan Lee (Department of Electrical Engineering) from the research group of Prof. Wonbin Hong at POSTECH received the Gold Prize at the 5th Undergraduate Creative Design Competition, held during the 2025 Winter Conference of the Korean Institute of Electromagnetic Engineering and Science (KIEES).

The award-winning work, titled “Thin, Multi-layer Dielectric Spectroscopy via Microwave Ellipsometry with a Metalens,” presents a novel methodology for analyzing the electrical properties of multilayer dielectric thin films, significantly expanding the application potential of metasurfaces.

In particular, the study introduces a precise wavefront control technique using a metalens, enabling microwave ellipsometry for material characterization. While conventional ellipsometry techniques have largely been limited to the optical frequency range, this approach overcomes that limitation and enables non-invasive and non-destructive characterization of materials in the microwave frequency band.

Through both experimental validation and theoretical modeling, the research demonstrated that the proposed technique can effectively extract complex electrical properties of multilayer dielectric thin films. The results are expected to open new possibilities for metasurface-based microwave measurement technologies.

Among the 22 papers presented in the competition, the team achieved the Gold Prize, demonstrating the excellence and innovation of their research.