This paper presents criteria for the onset of NQS effects derived from time transient device simulations and Sparameter measurements. For the first time it has been proved that e.g. a 10 µm NMOS transistor can be described up to 27 MHz and a 0.2 µm device up to 46 GHz by the quasistatic approach while the accuracy of the description of the inversion layer charge is still 99 %.

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 A dynamic model has been developed that is based on the Preisach approach for ferroelectric capacitors. It accounts for different switching reaction of the dipoles dependent on the applied voltage gradients. A method for extracting the necessary parameters by measuring the coercive voltage versus applied frequency is provided. The model was verified by testing capacitors of different geometries. Excellent agreement was achieved between our measurements and the corresponding circuit simulations. The simulation of a FeRAM-cell with our new dynamic model shows that the bit line signal decreases substantially with fast read/write times.

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A physics based compact model describing the fatigue behavior of ferroelectric capacitors has been developed. Fatigue is a gradual decrease of detectable polarization with increasing number of polarization cycles. This can be caused by trapped charges which pin dipoles near the interface to the electrode. In order to polarize those pinned dipoles they have to be separated from the trapped charges by a higher electrical force. This force has been described in our model by additional coercive voltages representing the different polarization response of the dipoles in the interface region in contrast to those in the inner region of the ferroelectric capacitor. Our model has been implemented into a common-used circuit simulator showing good agreement with measurements.