High performance 0.25 μm gate-length doped-channel AlGaN/GaN heterostructure field effect transistors grown on p-type SiC substrates

Abstract

Doped-channel heterostructure field effect transistors have been fabricated using Al/sub 0.2/Ga/sub 0.8/N/GaN heterostructures which were grown on p-type SiC substrates by low-pressure metal organic chemical vapor deposition (LP-MOCVD). These devices yielded excellent DC and RF performance with a drain saturation current, extrinsic transconductance, unity current-gain cutoff frequency (f/sub t/), and maximum frequency of oscillation (f/sub max/) of 1.43 A/ mm, 229 mS/mm, 53 GHz, and 58 GHz, respectively, for a 0.25 /spl mu/m gate length.