Submillimeter-Wave Amplifier Circuits Based on Thin Film Microstrip Line Front-Side Technology

Compact 500 to 750 GHz submillimeter-wave monolithic integrated circuit (S-MMIC) amplifiers have been developed, based on a thin-film microstrip line (TFMSL) front-side technology utilizing 35 and 20 nm metamorphic high electron mobility transistors (mHEMTs). By applying the 20 nm gate-length process, an eight-stage amplifier circuit achieved a small-signal gain of 23.1 dB at 584 GHz and more than 16 dB in the bandwidth from 500 to 634 GHz. Based on the 35 nm mHEMT technology, a ten-stage amplifier design demonstrated a linear gain of 15.6 dB at 716 GHz and more than 10 dB between 660 and 775 GHz. Advanced on-wafer calibration standards in combination with an improved transistor layout and a new small-signal model have been used to achieve an excellent agreement between modeled and measured S-parameters up to 900 GHz.