A Novel 100 MHz–45 GHz Input-Termination-Less Distributed Amplifier Design With Low-Frequency Low-Noise and High Linearity Implemented With A 6 Inch 0.15~ μ m GaN-SiC Wafer Process Technology

This paper describes a novel low-noise input-termination-less cascode distributed amplifier (DA) monolithic microwave integrated circuit (MMIC) design. The design was implemented with a 0.15 μm gate gallium nitride on silicon carbide GaN-SiC high electron mobility transistor (HEMT) 6 inch wafer process technology. The GaN MMIC achieves a bandwidth from 100 MHz-45 GHz with greater than 10 dB gain and previously benchmarked the first published mm-wave MMIC results produced on a 6 inch GaN on SiC wafer process technology. The unique input-gate-termination-less DA topology reduces the low-frequency noise figure (NF) of the conventional resistive-terminated DA without compromising the third order intercept point (IP3) linearity. The new design achieves 1.6 dB NF at 250 MHz and a NF improvement of at least 1 dB and as much as 4 dB or greater for frequencies below 5 GHz compared to the conventional DA approach. The GaN MMIC also achieves an average mid-band NF of 2.5-3 dB, a saturated output power (Psat) of 1 Watt, and a mid-band output IP3 of 38 dBm. The new design architecture combined with the inherent device characteristics of GaN-SiC technology can provide performance benefits for next-generation coherent fiber optic, instrumentation and advanced broadband radio architecture applications.