The resonant detection of terahertz radiation using a dispersive AlN/GaN multichannel high-electron-mobility transistor (HEMT) is analyzed and modeled in this paper. The proposed full-wave model is based on the concurrent solution of the complete hydrodynamic model (CHM) and Maxwell’s equations. The CHM is derived from the first three moments of the Boltzmann transport equation (BTE). Considering the variations of the electron temperature and transport parameters along the HEMT channel, this model well characterizes the electron–wave interaction in the device for both low- and high-field conditions. Moreover, the effect of the optical phonon modes of the GaN buffer, which cannot be ignored in the target terahertz frequency band, is described using the Lorentz dispersive model. Employing the developed model, the transmission spectrum of the device is extracted numerically using the finite-difference time-domain (FDTD) method for grating-gate single-, double-, and three-channel HEMT structures. The results show that, at a lattice temperature of 300 K for a GaN grating-gate HEMT with gate periodicity of 680 nm and gate width of 520 nm, at given resonance frequency and overall electron concentration, the resonance depth improves by about 2.7 dB in the three- compared with the single-channel structure. Moreover, it is shown that the detection performance of such a structure at 300 K is similar to the single-channel HEMT at a reduced temperature of 120 K. Therefore, the multichannel HEMTs can show notably improved resonant detection performance, enabling the design of resonant detectors with enhanced sensitivity at room temperature.

本文对AlN / GaN多通道高电子迁移率晶体管（HEMT）的太赫兹辐射共振检测进行了分析和建模。所提出的全波模型基于完整流体动力学模型（CHM）和麦克斯韦方程组的并行解。CHM是从玻耳兹曼输运方程（BTE）的前三个矩导出的。考虑到沿HEMT通道的电子温度和传输参数的变化，该模型很好地描述了低场和高场条件下器件中的电子波相互作用。此外，使用Lorentz色散模型描述了在目标太赫兹频带中不能忽略的GaN缓冲器的光子模式的影响。利用开发的模型，利用有限差分时域（FDTD）方法对光栅栅单通道，双通道和三通道HEMT结构进行数字提取。结果表明，在300 K的晶格温度下，对于具有680 nm的栅极周期性和520 nm的栅极宽度的GaN光栅-栅极HEMT，在给定的谐振频率和总电子浓度下，谐振深度可提高约2.7 dB。三通道与单通道结构相比。此外，表明在300 K的温度下这种结构的检测性能类似于在120 K的降低温度下的单通道HEMT。因此，多通道HEMT可以显着提高谐振检测性能，从而可以进行谐振设计。检测器在室温下灵敏度更高。