State-of-the-Art Room Temperature Operable Zero-Bias Schottky Diode-Based Terahertz Detector Up to 5.56 THz

Abstract

We present the characterization of a Zero-bias Schottky diode-based Terahertz (THz) detector up to 5.56 THz. The detector was operated with both a table-top system until 1.2 THz and at a Free-Electron Laser (FEL) facility at singular frequencies from 1.9 to 5.56 THz. We used two measurement techniques in order to discriminate the sub-ns-scale (via a 20 GHz oscilloscope) and the ms-scale (using the lock-in technique) responsivity. While the lock-in measurements basically contain all rectification effects, the sub-ns-scale detection with the oscilloscope is not sensitive to slow bolometric effects caused by changes of the IV characteristic due to temperature. The noise equivalent power (NEP) is 10 pW/Hz in the frequency range from 0.2 to 0.6 THz and 17 pW/Hz at 1.2 THz and increases to 0.9 μW/Hz at 5.56 THz, which is at the state of the art for room temperature zero-bias Schottky diode-based THz detectors with non-resonant antennas. The voltage and current responsivity of ∼500 kV/W and ∼100 mA/W, respectively, is demonstrated over a frequency range of 0.2 to 1.2 THz with the table-top system.

Terahertz bow-tie diode based on asymmetrically shaped AlGaN/GaN heterostructures

“…Although the NEP values of BT diodes are still inferior to those of the state-of-the-art Schottky diodes, FMB diodes and TeraFET detectors [5,20,31], from a technological point of view, the fabrication technology of BT diodes is less demanding. Furthermore, the AlGaN/GaN BT diodes are expected to have an outstanding chemical and physical stability and electrostatic robustness due to the material properties of gallium nitride.…”

“…The evolution of terahertz (THz) science and technology enable new applications in wireless communication, spectroscopic imaging, chemical and biological sensing, but still requires the development of fast, sensitive and room-temperature THz detectors [1,2]. Of particular interest are semiconductor based sensors which can be integrated onchip implementing scalable planar schemes [3][4][5]. The detectors based on hot-electron effects are attractive due to their high sensitivity and de-tection capabilities achieved in the broadband spectrum [6][7][8].…”

Terahertz communication: detection and signal processing

“…Schottky diodes, in conjunction with HEMTs, represent a class of rapid detectors capable of achieving sub-nanosecond temporal resolutions, with their speed largely constrained by their RC time constants, which can exceed 1 THz. The compact size, room-temperature operability, and cost-effectiveness of these detectors enhance their practicality and ease of handling, rendering them suitable for a wide range of applications, notably diagnostics at THz-generating particle accelerator facilities [68].…”

Terahertz Detection with Graphene FETs: Photothermoelectric and Resistive Self-Mixing Contributions to the Detector Response

“…These should be cost-effective, compact, integrable into arrays, and compatible with room-temperature operation and mainstream semiconductor manufacturing processes. In this context, the THz field-effect transistors (TeraFETs) have evolved from the early proofs of concept − to a promising family of THz detectors, competing with the more established diode-based detectors. − In particular, they achieve high sensitivities with optical noise-equivalent powers (NEPs) as low as 20 pW/√Hz (see also Table ) and subnanosecond detection speed, − which also makes them suitable for coherent heterodyne detection. − …”