A 25.5–31GHz Power Amplifier Using Enhancement-Mode High-K Dielectric GaN MOS-HEMTs in 300mm GaN-on-Si Technology

This paper presents the design and characterization of a fully integrated 25.5–31GHz power amplifier (PA) using enhancement-mode high-k dielectric Gallium nitride (GaN) MOS-HEMTs in 300mm GaN-on-Si technology. The two-stage PA achieves a peak S21 of 27.7dB at 26.6GHz with a 3-dB bandwidth of 5.5GHz (20.1% fractional bandwidth). With a Li-ion battery compatible 4V supply, the measured Psat, peak PAE, and linear gain at 30GHz are 25.3dBm, 38.7%, and 26.6dB, corresponding to a PA figure-of-merit (FOM) of 97.3dB. The core area of the PA is 0.097mm², enabling compact integration into phased array systems in mobile devices. This is the first demonstration of mmWave circuits using enhancement-mode high-k GaN MOS-HEMTs in 300mm GaN-on-Si technology.