Low-Voltage Operation AlInN/GaN HEMTs on Si with High Output Power at sub-6 GHz

This paper describes the DC and RF performance of AlInN/GaN HEMTs on Si substrates for low-voltage operation to meet the demand of user equipment. By adapting the regrowth ohmic structure, low on-resistance of 0.6 Ω-mm was achieved due to the reduction of the contact resistance. Even with the relatively long gate length of 0.3 μm, lower voltage operation was achieved compared to other reported work. The obtained f
max
of 53.8 GHz exceeds the requirements of 5G mobile communication applications for the sub-6 GHz frequency range. Large-signal measurements on a gate width of 10x100 μm device exhibited a saturated power density of 1.52 W/mm and power added efficiency of 62.7 % at 5 GHz biased at V
ds
of 5 V. The device also exhibited excellent performance between V
ds
of 1.5 V and 12 V. To the best of our knowledge, this represents the highest RF performance with low-voltage operation for a GaN HEMT in the sub-6 GHz region.