Variability-aware MMIC design through multiphysics modelling

We present a novel multiphysics approach to the variability-aware modelling of MMIC stages, including technological variations in both the active devices and in the passive structures used to implement the matching networks. The models are based on accurate physical simulations via the TCAD numerical analysis of the active device, and electromagnetic simulations of the passives. Black-box models are then extracted and implemented into circuit simulators, using parameter-dependent X-parameters and scattering matrix. In both cases, the link with the underlying technology is always retained. After model validation, we present the statistical analysis of an X-band GaAs power amplifier. We show that the stage is highly affected by process induced variability, with spreads up to 3 dB of output power, 1.5 dB of operative gain, and more than 10 percentage points of drain efficiency.