Highly uniform AlGaN/GaN power HEMT on a 3-inch conductive N-SiC substrate for wireless base station application

Highly uniform AlGaN/GaN high electron mobility transistors (HEMTs) were fabricated on a low-cost 3-inch conductive n-SiC substrate for the first time. Average values of threshold voltage (Vth) and transconductance (gm) of AlGaN/GaN HEMT were -1.55V and 194 mS/mm. Standard variations of those values were only 0.15V and 3.9mS/mm across an entire 3-inch conductive substrate. The 1-mm-gate-periphery GaN HEMT chip, which was operated at 60V, achieved high CW output power density of 7.0W/mm, with a high linear gain of 22.2dB and power added efficiency (PAE) of 70% at 2.14GHz. Standard variations of power density, linear gain and PAE at 50V were only 0.42W/mm, 0.2dB and 3.0 point, respectively. This low-cost highly uniform high-gain chip technology is sufficient for mass production of wireless base station application using GaN-HEMTs.