Integral fabrication of terahertz hollow-core metal rectangular waveguides with a combined process using wire electrochemical micromachining, electrochemical deposition, and selective chemical dissolution

  • Xiaolei Bi
  • Yongbin ZengEmail author
  • Xingda Dai
  • Ningsong Qu


The application requirements of terahertz hollow-core metal rectangular waveguides with a high-working frequency have become increasingly urgent with the rapid development of terahertz technology. Integral fabrication of terahertz hollow-core metal rectangular waveguides can improve considerably the transmission performance of terahertz signals. However, with current manufacturing techniques, the high-precision integral fabrication of high-working-frequency terahertz hollow-core metal rectangular waveguides is difficult owing to their characteristically small end face size and the need for strict dimensional accuracy and high internal surface quality. In this paper, an innovative combined process of wire electrochemical micromachining, electrochemical deposition, and selective chemical dissolution is proposed firstly to overcome this puzzle. Taking the fabrication of an integral 1-THz hollow-core metal rectangular waveguide as an example, the manufacturing methods involved in each step are described particularly, together with the corresponding experimental investigations. With the end face size of 127 μm × 254 μm, edge radius less than 5 μm, and internal surface roughness less than 0.08 μm, the experimental results satisfy the design requirements for a 1-THz hollow-core metal rectangular waveguide. This study demonstrates that the proposed combined process is flexible, controllable, and suitable for the high-precision integral fabrication of high-working-frequency terahertz hollow-core metal rectangular waveguides.


Terahertz hollow-core metal rectangular waveguide High-precision integral fabrication Wire electrochemical micromachining Gold micro-electroplating Copper micro-electroforming 


Funding information

This project was supported by the National Natural Science Foundation of China (51775276), the Natural Science Found ation of Jiangsu Province (BK20192007), and the Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX19_0163).


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Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2019

Authors and Affiliations

  • Xiaolei Bi
    • 1
  • Yongbin Zeng
    • 1
    Email author
  • Xingda Dai
    • 1
  • Ningsong Qu
    • 1
  1. 1.National Key Laboratory of Science and Technology on Helicopter TransmissionNanjing University of Aeronautics and AstronauticsNanjingChina

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