Enhancement of terahertz coupling efficiency by improved antenna design in GaN/AlGaN high electron mobility transistor detectors

Abstract

An optimized micro-gated terahertz detector with novel triple resonant antenna is presented. The novel resonant antenna operates at room temperature and shows more than a 700% increase in photocurrent response compared to the conventional bowtie antenna. In finite-difference-time-domain simulations, we found the performance of the self-mixing GaN/AlGaN high electron mobility transistor detector is mainly dependent on the parameters Lgs (the gap between the gate and the source/drain antenna) and Lw (the gap between the source and drain antenna). With the improved triple resonant antenna, an optimized micrometer-sized AlGaN/GaN high electron mobility transistor detector can achieve a high responsivity of 9.45 × 102 V/W at a frequency of 903 GHz at room temperature.

Room-temperature terahertz detection based on CVD graphene transistor

“…[3] Fieldeffect transistors (FETs) based on high-electron-mobility twodimensional electron gas (2DEG) have been proved to be such detectors suitable for room-temperature applications. [4,5] Graphene has attracted great attention due to its distinctive physical properties, such as zero band gap and high carrier mobility. [6] FETs based on graphene produced by mechanical exfoliation has been recently demonstrated for terahertz detection at 300 GHz.…”

Mapping an on-chip terahertz antenna by a scanning near-field probe and a fixed field-effect transistor

“…[2] In various THz detectors, antennas are commonly applied to feed incident THz electromagnetic (EM) radiation into the active region of the detectors. [3][4][5][6][7][8][9] The efficiency of these antennas is crucial for high sensitivity and is largely determined by the near-field properties. The near-field distribution is usually obtained by performing a finite-element analysis of the EM wave.…”

Investigation of high sensitivity radio-frequency readout circuit based on AlGaN/GaN high electron mobility transistor

“…AlGaN/GaN heterostructure has the advantages of the discontinuity of conduction band ∆E and large polarization efficient in nitride, which results in a large piezoelectric polarization in the epitaxial layer of GaN. [6][7][8] The high concentration of two-dimensional electron gas (2DEG) is observed at the interface of AlGaN/GaN heterostructure. Therefore, Al-GaN/GaN HEMT is an important tunable material for RF and microwave devices by controlling the concentration of 2DEG under gate voltage (V g ).…”