High performance double recessed Al(0.2)Ga(0.8)As/In(0.25)Ga(0.75)As PHEMTs for microwave power applications

Double recessed T-gate Al(0.2)Ga(0.8)Aa/In(0.25)Ga(0.75)As pseudomorphic HEMTs with 0.3 mu m gate length and different upper recess widths have been processed and analyzed. Systematic investigations concerning the correlation between drain ledge, breakdown voltage and power performance have been carried out. An optimum upper recess width has been identified which yields to a high drain-source breakdown voltage of about 24 V. A state of the ail saturated output power density of 1080 mW/mm at 2 GHz is demonstrated under CW-mode of operation. DC and power measurements are performed on wafers which are not thinned.