The previous versions of Minimos-NT provided only two simulation modes: the basic steady-state DC mode and the transient simulation mode that takes all time derivatives in the time domain into account. Using the transient mode small-signal analysis is very inconvenient and costly, which was the basic motivation to consider development of a small-signal or AC analysis mode providing the capability to simulate directly in the frequency domain. In addition to the single device simulator, the circuit simulator of Minimos-NT has been equipped with small-signal capabilities.

After the integration of new assembly and solver modules, which are also capable of handling complex-valued linear equation systems, Minimos-NT was extended by several features for small-signal simulations: for example, calculation of the admittance and scattering matrices and the efficient extraction of various small-signal parameters (Y-, Z-, S- and H-parameters) or related figures of merit (cut-off frequency, maximum oscillating frequency, etc.). In order to take parasitics introduced by the measurement setup into account, single devices can be embedded in a standard two-port circuit, which allows the extrinsic parameters to be extracted easily.

The in-house solver module provides two nonstationary iterative methods, Bi-CGStab and GMRES(m), in combination with an incomplete factorization preconditioner. To also meet future requirements, two external solver modules have been evaluated and plugged into the solver module. A further speed-up of the simulators is highly appreciated, especially for three-dimensional process or device simulations, e.g., for the FinFET structure cut-out shown in the figure. The simulators are now able to employ the parallel direct solver Pardiso as well as four solvers from the Algebraic Multigrid Methods for Systems package.