0.15 μm gate length InAlAs/InGaAs power metamorphic HEMT on GaAs substrate with extremely low noise characteristics

Abstract

The 0.15 /spl mu/m gate-length power metamorphic HEMTs (MHEMT) with wide head T-shaped gate has been fabricated and the DC, microwave, and noise performance of the device were characterized. The MHEMT device shows the DC output characteristics having an extrinsic transconductance of 740 mS/mm and a threshold voltage of -0.75 V. The f/sub T/ and f/sub max/ obtained for the 0.15 /spl mu/m /spl times/ 100 pm MHEMT device are 150 GHz and 240 GHz, respectively. The MHEMTs exhibit the minimum noise figure, NF/sub min/, of 0.79 dB and associated gain of 10.5 dB at 26 GHz. The NF/sub min/ measured at 40 GHz is 1.21 dB with associated gain of 6.41 dB. This noise data is the lowest value ever reported for power MHEMT devices with InGaAs channel of 53% In. The excellent noise characteristics might result from the low gate resistance due to the wide head T-shaped gate and the improved device performance.