AlGaN/GaN HEMTs on SiC: towards power operation at V-band

The operation of AlGaN/GaN HEMTs on SiC substrate at V-band frequencies (50-75 GHz) is discussed. Both common source and dual-gate AlGaN/GaN HEMTs on SiC substrate are optimized and investigated by active and passive load-pull measurements. At 60 GHz, a power density of /spl ges/0.5 W/mm can be measured for a small common source AlGaN/GaN HEMT limited so far by the available input power of the newly developed load-pull system. A common source HEMT with W/sub g/=0.18 mm yields a power density of 1.9 W/mm at 40 GHz and a linear power gain of /spl ges/5 dB at 60 GHz, while several dual-gate AlGaN/GaN HEMTs of W/sub g/=0.18 mm and 0.36 mm yield MSG/MAG values /spl ges/12 dB at 60 GHz.