The dc and high frequency performances of Al composition Graded Channel AlGaN/GaN high electron mobility transistor on GaN substrate was investigated and compared with Conventional AlGaN/GaN HEMT. The high frequency characteristics were measured on both the AlGaN/GaN HEMTs scaling the gate length from 800 nm to 50 nm. The 50 nm gate length Graded Channel AlGaN/GaN HEMT exhibited the highest drain current of 2.48 A/mm and transconductance of 0.32 S/mm respectively at a drain voltage of V_D = 10 V. Also the transconductance curve of the Graded Channel HEMT is flatter than that of conventional GaN HEMT. The flatter transconductance curve reduces the power gain roll off in Graded Channel HEMT and thus gives improved performance in terms of device linearity. The current gain cutoff frequency f_T = 126.5 GHz was obtained for the Graded Channel HEMT at a gate length of 50 nm. This accounts to 61.6% increase in f_T when compared to conventional GaN HEMT at the same gate length of 50 nm.

研究了在GaN衬底上的Al组成梯度沟道AlGaN / GaN高电子迁移率晶体管的直流和高频性能，并将其与常规AlGaN / GaN HEMT进行了比较。在这两种AlGaN / GaN HEMT上都测量了高频特性，将栅长从800 nm缩小到50 nm。在漏极电压V _D  = 10 V时，栅极长度为50 nm的梯度沟道AlGaN / GaN HEMT的最大漏极电流分别为2.48 A / mm和0.32 S / mm 。比传统的GaN HEMT更平坦。更平坦的跨导曲线减少了渐变通道HEMT中的功率增益衰减，从而在器件线性度方面提高了性能。电流增益截止频率f _T 对于梯度通道HEMT，在50 nm的栅极长度处获得了= 126.5 GHz。与在50 nm的相同栅极长度下的传统GaN HEMT相比，这意味着f _T会增加61.6％。