Graded-barrier graded-channel InP pseudomorphic power HEMT with 40% power added efficiency and 200 mW output power at 60 GHz

Summary form only given. We present state-of-the-art power and PAE results of InGaAs-InAlAs-InP HEMTs with optimized graded channel and graded Schottky barrier layers which demonstrate, for the first time, that InP-based HEMTs have a considerably better power/PAE combination than GaAs-based HEMTs at V-band. The 0.15 /spl mu/m gate length, eight gate finger, 500 /spl mu/m wide InP HEMTs were measured in a fixture under continuous wave (CW) conditions and showed 23 dBm (200 mW) output power and 40% PAE at 60 GHz with an input power of 17 dBm, a drain bias of 3 V, and a drain current of 125 mA. These results represent the best reported V-band power/PAE performance to date, and a comparison of these results with previously reported results for both InP- and GaAs-based HEMTs is shown. Our state-of-the-art results are attributed to the use of an optimized heterostructure incorporating pseudomorphic graded channel and graded Schottky barrier layers, and the use of compact 15 /spl mu/m/spl times/25 /spl mu/m dry etched through-substrate vias (substrate thickness of 50 /spl mu/m). The heterostructure was designed to achieve high gain, current (Imax) and breakdown voltage; all of which are requirements for a device with high power and PAE.