A simple SPICE model for Negative Capacitance Field-Effect Transistors and its applications

In this paper, a reasonably accurate and understandable SPICE model for negative capacitance field-effect transistors (NCFETs) based on time-dependent Landau-Khalatnikov equation is proposed. Different from previous circuit compatible models, which solve gate charge self-consistently with the transistor equations, we introduce a charge conserved capacitor in series with the gate to extract the gate charge. Our model predicts dynamic behaviors of NCFETs. The basic electrical characteristics of NCFETs show that internal voltage amplification and sub-60 mV/decade subthreshold swing (SS) can be achieved. A ring oscillator analysis shows smaller propagation delay of NCFETs compared with MOSFETs when the supply voltage (V
_DD
) is below 0.3V and damping constant is 0.01Ω·m. Total energy consumption per cycle of the ring oscillator based on NCFETs is smaller than MOSFETs at V
_DD
=0.2V. NCFETs-based SRAM shows smaller write time and access time whose time delay reduces by 39% and 83% when V
_DD
=0.2V and T
_FE
=10nm. Besides NCFETs-based SRAM shows 12% larger hold stability, 84% larger read stability and larger write stability than MOSFETs-based SRAM. We use the NCFETs with hysteresis behavior as a Schmitt trigger which can work at V
_DD
=0.2V. The Schmitt trigger has a tunable hysteresis which is tuned by the thickness of ferroelectric thin film. Our results reveal that the NCFETs have the potential for low-power circuit and functional circuits applications.