An ultra-low-power MMIC amplifier using 50-nm $\delta$ -doped $\hbox{In}_{0.52}\hbox{Al}_{0.48}\hbox{As/In}_{0.53} \hbox{Ga}_{0.47}\hbox{As}$ metamorphic HEMT

An ultra-low-power monolithic amplifier using 50-nm gate-length GaAs metamorphic high-electron-mobility transistor (MHEMT) has been designed and fabricated by a coplanar waveguide monolithic microwave integrated circuit process. A double (5-doped In0.52Al0.48As/In0.53Ga0.47As MHEMT technology with optimal doping profiles was used to achieve both ultra-low dc power consumption and good dynamic-range performance. The single-stage amplifier operates in the 24-GHz band and shows typical gain of 7.2 dB, ±0.5 dB bandwidth of 1.2 GHz, return losses better than 9 dB, and input IP3 (IIP3) of +3 dBm while consuming only 0.9 mW of dc power. These experimental results demonstrate the outstanding potential of MHEMT technology for ultra-low-power applications such as wireless sensor networks