High-responsivity, low-noise, room-temperature, self-mixing terahertz detector realized using floating antennas on a GaN-based field-effect transistor

Using only optical lithography, we have fabricated a GaN/AlGaN high-electron mobility transistor with distinctive source and drain antennas electrically isolated from the electron channel. Working at room temperature, it efficiently detects terahertz radiation via self-mixing, with a responsivity (3.6 kV/W) exceptionally high for a III-V device and with a noise d40pW/root Hz just above the thermal limit. Performance improves at 77 K. While the device itself is micrometer-sized, our modeling indicates the asymmetric antennas induce a rather localized (< 200 nm) region of strong self-mixing. Thus, a nanometer-scale active region is achieved by design and without recourse to electron-beam lithography. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3673617]

我们仅使用光学光刻技术制造了一种氮化镓/氮化铝镓高电子迁移率晶体管，其独特的源极和漏极天线与电子沟道电隔离。在室温下工作时，它通过自混频有效地检测太赫兹辐射，对于III - V族器件而言，其响应度（3.6 kV/W）极高，且噪声为40 pW/√Hz，刚好高于热极限。在77 K时性能提高。虽然该器件本身是微米尺寸的，但我们的建模表明非对称天线诱导出一个相当局域化（<200 nm）的强自混频区域。因此，通过设计实现了纳米级的有源区域，且无需借助电子束光刻技术。（C）2012美国物理学会。[doi: 10.1063/1.3673617]