We report on the design and characterization of a novel backside-radiating antenna-coupled direct terahertz detector fabricated in 65 nm CMOS technology. The novelty of the design lies in the low-metal coverage of the biquad antenna geometry, which adapts well to the particular challenging conditions of on-chip antenna integration in silicon and allows optimization for a versatility of operation conditions. The biquad antenna was modified here to achieve wideband radiation and matching to a gate-coupled single-finger field-effect transistor with ac open condition at the drain terminal. The successful detector performance was the result of a careful treatment of transistor, antenna, and optics from a codesign perspective, since the beginning of the design. This included the frequency-dependent complex impedance for optimum matching, the technology restrictions to ensure proper chip fabrication, and the overall detection efficiency after backing the device with a silicon lens. Calibrated detector measurements for 7777 Hz modulation frequency yielded minimum optical noise-equivalent-power (NEP) of 25 pW/$\sqrt{\,}$Hz at 1 THz, with NEP values below 50 pW/$\sqrt{\,}$Hz in the 0.84–1.29 THz frequency range. These figures achieve state-of-the-art of wideband CMOS-based detectors and are only a factor of ${{\sim}2}$ inferior to the best reported narrowband devices close to 1 THz.

中文翻译：

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通过 CMOS 中的新型双二阶天线耦合低 NEP 检测器在 1 THz 附近进行宽带感测

我们报告了一种采用 65 nm CMOS 技术制造的新型背面辐射天线耦合直接太赫兹探测器的设计和表征。该设计的新颖之处在于双二阶天线几何结构的低金属覆盖率，它很好地适应了硅片上天线集成的特殊挑战条件，并允许针对操作条件的多功能性进行优化。此处对双二阶天线进行了修改，以实现宽带辐射并匹配栅极耦合单指场效应晶体管，在漏极端具有交流开路条件。成功的探测器性能是从设计之初就从协同设计的角度仔细处理晶体管、天线和光学器件的结果。这包括用于最佳匹配的频率相关复阻抗，确保正确芯片制造的技术限制，以及用硅透镜支持设备后的整体检测效率。7777 Hz 调制频率的校准检测器测量产生的最小光学噪声等效功率 (NEP) 为 25 pW/$\sqrt{\,}$Hz 在 1 THz，NEP 值低于 50 pW/$\sqrt{\,}$Hz 在 0.84–1.29 THz 频率范围内。这些数字实现了基于宽带 CMOS 的检测器的最新技术水平，并且仅是${{\sim}2}$ 不如报告的最好的接近 1 THz 的窄带设备。