基于AlN/GaN异质结的Ka波段GaN低噪声放大器研制

Fabrication of Ka-band GaN Low Noise Amplifier Based on AlN/GaN Heterojunction

报道了基于AlN/GaN异质结的Ka波段低噪声放大器的研制结果。在SiC衬底上生长AlN/GaN异质结材料结构,采用电子束直写工艺制备了栅长70 nm的"T"型栅结构。器件最大电流密度为1.50 A/mm,最大跨导为650 mS/mm,通过S参数测试外推特征频率和最大频率分别为105 GHz和235 GHz。基于70 nm工艺制备的自偏压三级低噪声放大器,在33~40 GHz小信号增益大于27 dB,典型噪声系数为1.5 dB。

The results of Ka-band low noise amplifier based on AlN/GaN heterojunction were reported in this paper.Electron-beam lithography was employed to fabricate a 70 nm T-shaped gate on the AlN/GaN heterojunction structure,which was epitaxially grown on SiC substrate.This device exhibits a maximum current density of 1.50 A/mm and a maximum trans-conductance of 650 mS/mm.An extrinsic characteristic frequency(f_(T))of 105 GHz and a maximum oscillation frequency(f_(max))of235 GHz are deduced from S-parameter.The self-bias three-stage Ka-band low-noise amplifier based on 70 nm process has a small signal gain of greater than 27 dB and a typical noise figure of 1.5 dB between 33~40 GHz.