An ultra-broadband low-noise traveling-wave amplifier based on 50nm InGaAs mHEMT technology

A monolithic integrated eight-stage traveling-wave amplifier (TWA) is presented that has been developed and fabricated using a 50nm InGaAs metamorphic HEMT technology. High-impedance coplanar waveguides (CPW) are used as compensation for the input and output capacitances of the stages, consisting of two transistors in a cascode configuration. A small signal gain of 11dB with a ripple of around ±1dB and a 3dB bandwidth of more than 110GHz is achieved. The noise figure (NF) is as low as 2.5dB at the best and less than 5dB for frequencies up to 90GHz. Furthermore, the amplifier provides an 1-dB-compression-point of 7dBm and a saturated output power of about 11dBm at 75GHz.