Towards Very High Frequency Simulators for Active Device Modelling

In this paper physics based computer-aided simulation of microwave nonlinear circuits, completely performed in the frequency domain with spectral balance (SB), is addressed. The completely frequency-domain approach allows easy inclusion of frequency-dependent parameters of the semiconductor, especially important at very high frequencies (e.g. dielectric constant), and easy and straightforward coupling to the passive external environment. The absence of time-frequency domain transformations typical of harmonic balance schemes allows easy extension to multitone analysis. This technique is suitable for develop new CAD tools useful for the design of microwave integrated components and monolithic microwave integrated circuits especially when "global analysis" is request and multitone excitation is present. Simulation results, for both the SB and a classical FDTD methods, are presented and compared in terms of complexity and CPU load time, for a quasi-two-dimensional hydrodynamic physical model of a MOSFET device