In this letter, a new 90° coupler with a symmetric coupled-line structure featuring the use of the tuning multiple floating metals technique is designed, analyzed, and verified for subterahertz (THz) applications; this new coupler was fabricated on the standard Taiwan Semiconductor Manufacturing Company (TSMC) 0.18- $\mu \text{m}$ 1P6M CMOS process. With the proposed structure, the impedances of even and odd modes can be designed individually to simultaneously optimize the performance in terms of insertion loss, phase balance, amplitude balance, isolation, and reflection coefficients. The bandwidths of phase imbalance (±3°) and amplitude imbalance (±1 dB) are 162 and 100 GHz, respectively. Reflection coefficients less than −20 dB are reached at 0.2–184 GHz, and isolation higher than 20 dB is from 0.2 to 200 GHz.

中文翻译：

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采用 0.18-μm CMOS 封装的 0.6-dB 低损耗和 3–165 GHz 宽带相位差 Sub-THz 耦合器

在这封信中，针对亚赫兹 (THz) 应用设计、分析和验证了一种具有对称耦合线结构的新型 90° 耦合器，该耦合器采用调谐多浮动金属技术。这种新型耦合器是在标准台积电 (TSMC) 0.18- 上制造的 $\mu \text{m}$1P6M CMOS工艺。使用所提出的结构，可以单独设计偶模和奇模的阻抗，以同时优化插入损耗、相位平衡、幅度平衡、隔离和反射系数方面的性能。相位不平衡 (±3°) 和幅度不平衡 (±1 dB) 的带宽分别为 162 和 100 GHz。反射系数小于 -20 dB 在 0.2–184 GHz 范围内达到，高于 20 dB 的隔离度在 0.2 至 200 GHz 范围内。