Current Optics and Photonics

Optical Society of Korea (한국광학회)
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Characterization of Thickness and Electrical Properties of Ni-Cr Thin Films via Terahertz Time-domain Spectroscopy

  • Sunghun Kim (Department of Biomedical Engineering, Inje University) ;
  • Inhee Maeng (YUHS-KRIBB Medical Convergence Research Institute, Yonsei University College of Medicine) ;
  • Hyeon Sang Bark (Division of Applied Photonics System Research, Advanced Photonics Research Institute, Gwangju Institute of Science and Technology) ;
  • Jungsup Byun (Gimhae Biomedical Center, Gimhae Biomedical Industry Promotion Agency) ;
  • Jae Hun, Na (Gimhae Biomedical Center, Gimhae Biomedical Industry Promotion Agency) ;
  • Seho Kim (Gimhae Biomedical Center, Gimhae Biomedical Industry Promotion Agency) ;
  • Myeong Suk Yim (Gimhae Biomedical Center, Gimhae Biomedical Industry Promotion Agency) ;
  • Byung-Youl Cha (Gimhae Biomedical Center, Gimhae Biomedical Industry Promotion Agency) ;
  • Youngbin Ji (Gimhae Biomedical Center, Gimhae Biomedical Industry Promotion Agency) ;
  • Seung Jae Oh (YUHS-KRIBB Medical Convergence Research Institute, Yonsei University College of Medicine)
  • Received : 2023.06.19
  • Accepted : 2023.07.13
  • Published : 2023.10.25
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Abstract

We utilized terahertz time-domain spectroscopy (THz-TDS) to measure the thickness and electrical properties of nickel-chromium (Ni-Cr) films. This technique not only aligns well with traditional methods, such as haze-meter and transmission-densitometer measurements, but it also reveals the electrical properties and thickness of films down to a few tens of nanometers. The complex conductivity of the Ni-Cr thin films was extracted using the Tinkham formula. The experimental values closely aligned with the Drude model, indicating the reliability of our Ni-Cr film's electrical and optical constants. The thickness of Ni-Cr was estimated using the complex conductivity. These findings emphasize the potential of THz-TDS in quality control of metallic nanofilms, pointing toward an efficient and nondestructive test (NDT) for such analyses.

Keywords

Acknowledgement

Institute of Information & Communications Technology Planning & Evaluation (IITP) grant, funded by the Korea government (MSIT) (Grant No. 2022-0-01044, Development of terahertz wave-based real-time intelligent brain tumor diagnosis system and technology).

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