High performacne InAs/AlSb HEMT with refractory iridium Schottky gate metal

In the work, a novel approach in fabricating high-performance of InAs/AlSb high electron mobility transistors using iridium (Ir) gate technology was proposed and investigated. The Ir-gate exhibited a superior metal work function which was beneficial for increasing Schottky barrier height (Ø_B) of InAs/AlSb heterostructure from 0.54 to 0.58 eV. The Ir-gate InAs/AlSb HEMT exhibited a Vth of -0.9 V, a maximum drain current of 270 mA/mm, and a peak transconductance of 420 mS/mm. In contrast, the Vth of Ti-gate InAs/AlSb HEMT was - 1.5 V, a maximum drain current of 257mA/mm, and a peak transconductance of 280mS /mm, respectively. It was suggested that Ir interface presented a high potential for high power transistor applications.