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Performance of a detector based on AlGaAs/InGaAs/GaAs-material system was studied. The detector was comprised of large serpentine array of high-electron mobility transistors (HEMTs) connected in series. The floating drain contact of each transistor (except the last one) served as a source for the next one. Detection of terahertz (THz) radiation was based on the excitation of electron plasma oscillations...
In this paper, we explain the THz detection mechanism in sub-threshold Si MOSFETs by exploiting the exponential dependence of channel electron density to the gate-source voltage. According to our theory, this high frequency non-linear dependence is the underlying mechanism for rectification of THz radiation. The maximum detection frequency is limited by dielectric relaxation time of the electrons...
Asymmetric-dual-grating-gate high-electron-mobility-transistors (ADGG-HEMTs) are expected for on-chip, sensitive, room-temperature operating, high-speed THz detectors. In this paper, we experimentally verify the high-speed response of an ADGG-HEMT by measuring its response to THz pulse generated from an injection-seeded THz-wave parametric generator (is-TPG). From the pulse response waveform of the...
We examine array configuration and silicon-lens integration of asymmetric-dual-grating-gate high-electron-mobility transistors (A-DGG HEMTs) as plasmonic terahertz detectors in order to enhance their external coupling efficiencies. We demonstrate 4-fold enhancement of the efficiency by an array of four series-connected detectors and 6-fold enhancement by the hyper-hemispherical silicon-lens integration...
We present new kind of terahertz (THz) Schottky detectors based on high-doped GaAs and AlGaAs/GaAs high electron mobility transistor (HEMT) structure using silver (Ag) metallic nanowires (NWs) with different diameters as air-bridge contact between the antenna and Schottky anode. The dielectrophoresis allows a simple alignment of the NWs and fabrication of submicron anode contacts with high cut-off...
We experimentally verify that the low external responsivity of nanostructured asymmetric-dual-grating-gate high-electron-mobility transistors (A-DGG HEMTs) as plasmonic terahertz detectors developed so far is attributed to their low external coupling efficiency. We separately demonstrate (1) 4-fold enhancement of the efficiency by an array of series-connected 4×1 detectors due to the increase in the...
The circuit structure is the key factor to determine the performance of CMOS THz detector. This paper presents four different structures of the terahertz detection circuit and their performance are analyzed. The common source(CS), common gate(CG), cascode and source differential circuits are designed in 0.18µm CMOS process. Under the conditions of the same input power level and transistor parameters,...
An overview of recent results concerning THz detection related to plasma nonlinearities in nanometer field effect transistors is presented. In particular, the research on the dynamic range of these detectors is described and two different technologies GaAs and GaN are compared. As a conclusion, we will show first real world applications of the plasma field effect transistors based THz detectors: demonstrators...
A design of low-noise wide band (0.05…1 GHz) cooled videoamplifier for prospective terahertz-range single-photon superconducting nanowire detectors is reported. The amplifier differs from existing prototypes by reduced consumption power (4mW) and ability of direct integration with the primary superconducting transducer to prevent false triggering caused by reflected waves in the detector-amplifier...
Fabrication and experimental tests of materials and optics for Terahertz range used in field effect transistor detectors arrays are described. The method using diffractive optics, fabricated in 3D printing technology, was used for tests with GaN/AlGaN based FETs sub-THz detectors working in 300 GHz atmospheric window. The lens arrays focus energy exactly on the detectors and additionally reduce mutual...
We present results of investigations of Plasma Assisted Molecular Beam Epitaxy (PAMBE) - grown GaN/AlGaN High Electron Mobility Transistor (HEMT) structures for fabrication of detectors and emitters operating in THz spectral range. These devices are standard HEMT structures but equipped with additional antennas that ensure THz radiation coupling. THz detectors and emitters were processed using different...
Performance limits of terahertz FET direct detection rectifying detectors operating in the broadband detection regime (long channel approximation) taking into account some extrinsic parasitics and detector-antenna impedance matching are considered.
Performance of terahertz THz field effect transistor (FET) direct detection rectifying detectors operating in the broadband detection regime taking into account some extrinsic parasitics and detector-antenna impedance matching is considered. Si metal oxide semiconductor FET (MOSFET) and GaAlN/GaN heterojunction FET (HFET) THz detectors in comparison with Schottky barrier diode (SBD) ones are discussed...
We investigate plasmonic THz detectors on Al-GaN/GaN hetero-structures for different configurations of the grating (symmetric or asymmetric pattern) and spatial modulation of the electron sheet density. The absorption spectra have been calculated for the different configurations and a few detectors have freshly been fabricated and the transmission and reflection spectra have been measured for one...
Self-heating effects in AlGaN/GaN high-electron mobility transistors (HEMTs) can notably reduce electron mobility and produce reliability concerns. Electrothermal characterization and appropriate thermal management are required to address this situation. This letter presents the measurement of channel temperature ($\mathbf {T_{ch}}$ ) of GaN HEMTs in multiple bias conditions with a good accuracy...
We proposed to explore extremely fast digital switching devices used in telecommunications for use as photon counting, energy resolving x-ray detectors. The HEMT (High Electron Mobility Transistor), used in ultra-fast switches and low noise amplifiers, offers a very low noise and high frequency operation. For this study a HEMT-based photon-counting energy-resolving ultra-fast x-ray detector with improved...
A terahertz detector using an InAlAs/InGaAs high-electron-mobility-transistor (HEMT) integrated with a bow-tie antenna was proposed and fabricated. By utilizing ballistic transport in the short-channel, a current sensitivity of 1.5 A/W at 280 GHz was achieved by the detector having 70-nm T-gate HEMT without applying drain bias. We also measured the drain bias dependence of current sensitivity on the...
We report on the development of a tunable antenna coupled intersubband terahertz (TACIT) detector based on GaAs/AlGaAs two dimensional electron gas. A successful device design and micro-fabrication process have been developed which maintain the high mobility (1.1×106 cm2/V-s at 10K) of a 2DEG channel in the presence of a highly conducting backgate. Gate voltage-controlled device resistance and direct...
We report on room-temperature plasmonic detection of the thermal emission from a black body in the terahertz and mid-infrared domains by dual-grating-gate InAlAs/InGaAs/InP high electron mobility transistors (HEMTs). In such detectors, the asymmetric grating gate of a large area acts as an effective antenna that improves the performance in the two spectral domains.
In principle, the photoresponse can be enhanced by scaling down the gate oxide thickness (tox), which is a key structural parameter for the channel 2DEG density modulation. By using our TCAD simulation framework, we found that the enhanced photoresponse by reducing tox has been originated from the increase of 2DEG density modulation by the improved subthreshold swing (SSW) of FET and the decrease...
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