Pseudomorphic InPHEMT's with dry-etched source vias having 190 mW output power and 40% PAE at V-band

We report state-of-the-art V-band power performance of 0.15-mu m gate lengt h InGaAs/InAlAs/InP HEMT's which have 15 mu m x 25 mu m dry etched through- substrate source vias (substrate thickness 50 mu m). The 500-mu m wide InP HEMT's were measured in fixture at 60 GHz and demonstrated an output power of 190 mW with 40% power-added efficiency (PAE) and 6.8 dB power gain at an input power of 16 dBm. These results represent the best combination of pow er and PAE reported to date at this frequency for any solid state device. T he results are achieved through optimization of the InP-based heterostructu re which incorporates a graded pseudomorphic InGaAs channel and a graded ps eudomorphic InAlAs Schottky barrier layer, and the use of 15 mu m x 25 mu m dry-etched through-substrate source vias.