On The Burn-in of GaN-on-Si MMIC High Power Amplifiers for SATCOM Applications

This paper deals with the burn-in and stability performance over time of some Monolithic Microwave Integrated Circuits (MMICs) High Power Amplifiers (HPAs) realized on a commercially available 100 nm gate length Gallium Nitride (GaN) on Silicon (Si) technology. In particular, the analysis involves two HPAs designed for the same application, i.e., satcom in the 17.3-20.2GHz Band, but based on different architectures, i.e. corporate and balance ones. Both designs are compliant with space reliability constraints and, despite the larger thermal resistance shown by the Si substrate with respect to the more common Silicon Carbide (SiC), they deliver up to 10 W of output power with about 30% of power added efficiency (PAE) and more than 23 dB of gain, from 17.3 GHz to 20.2 GHz. The MMICs have been subject of several tests carried out in continuous wave (CW) condition by monitoring endlessly (e.g., for 24 hours) their most relevant parameters i.e., output power, efficiency, gate and drain currents, in order to evaluate their stability over time. The registered results have shown almost negligible performance degradation, with the output power and PAE diminished of only 0.1 dB and 0.5%, respectively, thus revealing a significant maturity of the technology.