44 GHz hybrid low noise amplifiers using ion-implanted In/sub x/Ga/sub 1-x/As MESFETs

Hybrid low-noise amplifiers using ion-implanted In/sub x/Ga/sub 1-x/As MESFETs with 0.25- mu m T-gates have been developed at 44 GHz. The hybrid two-stage amplifier using these ion-implanted In/sub x/Ga/sub 1-x/As MESFETs achieved a noise figure of 3.6 dB with an associated gain of 14.4 dB at 44 GHz. When two of these amplifiers were cascaded, the four-stage amplifier demonstrated a gain of 30.5 dB at 44 GHz and 37 dB at 40 GHz. These results, achieved using low cost ion-implantation techniques, rival the best high-electron-mobility transistor (HEMT) results. >