太赫兹段慢波结构的微细加工技术研究新进展

Since terahertz (THz) radiation is characterized with strong penetrability, high security, good directionality, and wide bandwidth, the potential applications of THz technology are becoming increasing widespread, including national defense, deep space communications, remote high resolution imaging, concealed weapon or threat detection, biomedical diagnostics, etc. Vacuum electron device (VED) based on slow wave structures (SWSs) is the most promising solution for the generation of watt-level power at THz frequencies in a compact and affordable way. As a key part of VED, the physical design and fabrication technique for SWSs will directly influence the bandwidth and gain of VED. Therefore, this work reviews the development of the available microfabrication techniques for SWSs from three aspects, i.e., the specific types of SWSs suitable for working at THz frequencies, the requirement of manufacturing precision and surface quality for SWSs, and the corresponding microfabrication processing. The respective capabilities and application status of fabrication technologies for SWSs in the THz regime have been analyzed, with the main challenges needing to be responded to and the problems needing to be solved discussed in detail. This work is expected to present reference background for advancing the development of high frequency devices.