A comparison of devices with different source-drain gaps has been performed on AlInN/GaN high electron mobility transistors (HEMTs) grown on SiC. The cut-off frequency is effectively improved through shrinking source drain space and reducing gate parasitic capacitance. Our devices feature an f(T) of 188 GHz and f(MAX) of 200 GHz, which is the highest fMAX ever achieved to date for AlInN-based HEMTs. At 10 (20) GHz, our HEMTs exhibit a low minimum noise figure F-min of 0.62 (1.5) dB together with a high associated gain G(A) of 15.4 (13.3) dB. These Fmin values are among the lowest reported for deep submicrometer GaN HEMTs, and the GA are the best values so far in the literature, demonstrating the tremendous potential of AlInN/GaN HEMTs for microwave low-noise applications. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim