In this study, we demonstrate the effects of electron velocity modulation (Δve/ΔVgs) on the microwave power performance for AlGaN/GaN HFETs. In order to conduct the experiments, AlGaN/GaN HFETs with gate lengths ranging from 500 to 80 nm were fabricated. Electron transport was investigated by coupling a drift-diffusion solver with the Monte Carlo method. As gate lengths (Lg) varied from 500 to 200 nm, the increased polarization Coulomb field scattering led to an increase in Δve/ΔVgs and the stronger electric field (E) increased ve and enhanced the transconductance (gm), which in turn led to a greater power gain (Gp) in the HFETs. The higher power output (Pout) was also due to the increased ve that boosted the saturated output current (Ids,sat). The unique phenomenon that occurs from electron velocity modulation of AlGaN/GaN HFETs at electron densities (ns) < 3.42 × 1012cm−2 can be used as an effective mechanism to enhance the power gain of AlGaN/GaN HFETs.

中文翻译：

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电子速度调制对 AlGaN/GaN HFET 微波功率性能的影响


在这项研究中，我们展示了电子速度调制 （Δve/ΔVgs） 对 AlGaN/GaN HFET 微波功率性能的影响。为了进行实验，制造了栅极长度为 500 至 80 nm 的 AlGaN/GaN HFET。通过将漂移扩散求解器与 Monte Carlo 方法耦合来研究电子传输。当栅长 （Lg） 从 500 到 200 nm 变化时，极化库仑场散射的增加导致 Δve/ΔVgs 的增加，而更强的电场 （E） 增加了 ve 并增强了跨导 （gm），这反过来又导致 HFET 中的功率增益 （Gp） 更大。更高的功率输出 （Pout） 也是由于增加的 ve 提高了饱和输出电流 （Ids，sat）。在电子密度 （ns） < 3.42 × 1012cm-2 下，AlGaN/GaN HFET 的电子速度调制产生的独特现象可用作提高 AlGaN/GaN HFET 功率增益的有效机制。