A study of the electrical performances of AlInN/GaN High Electron Mobility Transistors (HEMTs) on SiC substrates is presented in this paper. Four different wafers with different technological and epitaxial processes were characterized. Thanks to intensive characterizations as pulsed-IV, [S]-parameters, and load-pull measurements from S to Ku bands, it is demonstrated here that AlInN/GaN HEMTs show excellent power performances and constitute a particularly interesting alternative to AlGaN/GaN HEMTs, especially for high-frequency applications beyond the X band. The measured transistors with 250 nm gate lengths from different wafers delivered in continuous wave (cw): 10.8 W/mm with 60% associated power added efficiency (PAE) at 3,5 GHz, 6.6 W/mm with 39% associated PAE at 10.24 GHz, and 4.2 W/mm with 43% associated PAE at 18 GHz.
