AlInN HEMT Grown on SiC by Metalorganic Vapor Phase Epitaxy for Millimeter-Wave Applications

In this work we present the epitaxial and device results of AIInN/GaN HEMTs grown on SiC by metalorganic vapor phase epitaxy. High quality AIInN/GaN HEMT structures with sub-10nm AlInN barrier were grown with very low Ga background level (<1%). The low R sh of 215 Ω/sq was obtained with an excellent standard deviation of 1.1 % across 3" wafers. Lehighton RT contactless Hall tests show a high mobility of 1617 cm 2 /V s and sheet charge density of 1.76 × 10 13 /cm 2 . DC characteristics of an AlInN/GaN HEMT with a gate length of 0.1 μm and 25 nm Al 2 O 3 passivation show maximum drain current (I DS,max ) of 2.36 A/mm at V GS = 2 V. Gate recessed devices with 0.15 μm gate length and 25 nm Al 2 O 3 passivation resulted in maximum transconductance (g m ) of 675 mS/mm, the highest value ever reported in AlInN transistors. Excellent frequency response was obtained. The maximum f T is 86 GHz and f max is 91.7 GHz.