Advanced Ferroelectric Modeling for BEOL Negative Capacitance Nanoelectromechanical Switches

Negative capacitance (NC) - achieved by adding a ferroelectric layer in series with the dielectric layer (air gap) of an electrostatic actuator - has been proposed as a means of reducing the pull-in voltage of a nano-electro-mechanical (NEM) switch without physically scaling down the gap size. This paper introduces a two-dimensional device simulation framework for NC NEM switches using the ferroelectric material hafnium zirconium oxide. The ferroelectric layer is simulated using both a simplified single polarization domain model and two different multi-domain models. While a dramatic reduction in pull-in voltage is confirmed for a single-domain ferroelectric, this benefit is predicted to be diminished for a multi-domain ferroelectric.