This paper presents the recent progress in the development of fabrication processes and device performance of recessed as well as non recessed AlGaN/GaN HEMTs at the University of Illinois. Maximum drain current density as high as 1.31 A/mm, record high extrinsic transconductance of 402 mS/mm, unity gain cut-off frequency (f/sub T/) of 107 GHz, and maximum frequency of oscillation (f/sub max/) of 148 GHz were demonstrated for recessed AlGaN/GaN HEMTs with a gate length of 0.15 /spl mu/m grown by MOCVD. Results for MBE-grown devices are also presented.