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We propose a parallel negative-capacitance field-effect transistor (P-NCFET) structure, in which a ferroelectric operating in its negative-capacitance region is placed in parallel with the gate and source terminals of a MOSFET. The P-NCFET is stabilized by combining careful matching of the ferroelectric with the gate capacitance along with simple feedback realized using current mirrors. The novel stabilization approach opens the possibility for a variety of new applications that exploit the negative capacitance of ferroelectrics to cancel capacitance in integrated circuits. As an example, we show the P-NCFET structure has a significantly higher unity-current-gain frequency ${f}_{T}$ compared to a conventional MOSFET. [ABSTRACT FROM AUTHOR]

Ferroelectric and negative-capacitance field-effect transistors (FeFETs and NCFETs) have recently garnered great attention as devices for applications in memory and low-power logic, respectively. As these technologies are pursued, it is critical to have a variety of measurement approaches, including methods familiar to the electron-device and microwave communities that can aid in fully understanding the behavior of ferroelectrics in FeFETs and NCFETs. In this paper, we propose and show the viability of using frequency-domain electrical measurement techniques employing the well-known microwave S-parameters, and their large-signal generalization and X-parameters. Our methods provide the means to trace the intrinsic polarization versus electric-field curve of the ferroelectric, i.e., with the parasitics de-embedded, thereby showing the innate ferroelectric response, which cannot be done using conventional techniques. These methods also enable extraction of all the parameters of the Landau–Khalatnikov equation, which is commonly used to model ferroelectric behavior in FeFETs and NCFETs. This paper hence takes a useful step toward methods familiar to the electron-device community that can help to better understand and optimize FeFET and NCFET technologies. [ABSTRACT FROM AUTHOR]

Recently, negative-capacitance FETs (NCFETs) have been proposed to reduce subthreshold slope and help continue supply-voltage scaling alongside channel-length scaling. We investigate the high-frequency switching behavior of NCFETs using the Landau–Khalatnikov equation to model ferroelectric materials. Multidomain interactions in the ferroelectric are considered, resulting in strong agreement with experimental measurements. Operation of NCFETs at gigahertz frequencies is investigated with this experimentally validated multidomain model. We find that the effectiveness of the voltage amplification in NCFETs is strongly dependent on the viscosity coefficient $\rho $ of the ferroelectric, and that a low \rho $ ( <0.1~\Omega \cdot \text {m} ) is required for the operation at the high gigahertz frequencies. [ABSTRACT FROM PUBLISHER]