We present results for the successful fabrication of low-loss THz metallic waveguide components using direct machining with a CNC end mill. The approach uses a split-block machining process with the addition of an RF choke running parallel to the waveguide. The choke greatly reduces coupling to the parasitic TM0 mode of the parallel-plate waveguide produced by the split-block. This method has demonstrated loss as low as 0.2 dB/cm at 280 GHz for a copper WR-3 waveguide. It has also been used in the fabrication of 3 and 10 dB directional couplers in brass, demonstrating excellent agreement with design simulations from 240-260 GHz. The method may be adapted to structures with features on the order of 200 μm.

中文翻译：

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直接加工带有射频扼流圈的低损耗太赫兹波导元件


我们展示了使用 CNC 立铣刀直接加工成功制造低损耗太赫兹金属波导组件的结果。该方法采用分块加工工艺，并添加与波导平行运行的射频扼流圈。该扼流圈极大地减少了与分割块产生的平行板波导的寄生 TM0 模式的耦合。该方法已证明铜 WR-3 波导在 280 GHz 时损耗低至 0.2 dB/cm。它还用于制造 3 dB 和 10 dB 黄铜定向耦合器，证明与 240-260 GHz 的设计模拟具有良好的一致性。该方法可适用于具有 200 μm 数量级特征的结构。