High-performance HZO/InAlN/GaN MISHEMTs for Ka-band application

This paper reports on the demonstration of microwave power performance at 30 GHz on InAlN/GaN metal–insulator–semiconductor high electron mobility transistor (MISHEMT) on silicon substrate by using the Hf 0.5 Zr 0.5 O 2 (HZO) as a gate dielectric. Compared with Schottky gate HEMT, the MISHEMT with a gate length ( L G ) of 50 nm presents a significantly enhanced performance with an ON/OFF current ratio ( I ON / I OFF ) of 9.3 × 10 7 , a subthreshold swing of 130 mV dec −1 , a low drain-induced barrier lowing of 45 mV V −1 , and a breakdown voltage of 35 V. RF characterizations reveal a current gain cutoff frequency ( f T ) of 155 GHz and a maximum oscillation frequency ( f max ) of 250 GHz, resulting in high ( f T × f max ) 1/2 of 197 GHz and the record high Johnson’s figure-of-merit (JFOM = f T × BV) of 5.4 THz V among the reported GaN MISHEMTs on Si. The power performance at 30 GHz exhibits a maximum output power of 1.36 W mm −1 , a maximum power gain of 12.3 dB, and a peak power-added efficiency of 21%, demonstrating the great potential of HZO/InAlN/GaN MISHEMTs for the Ka-band application.