Electrical Characteristics of Nanoelectromechanical Relay with Multi-Domain HfO2-Based Ferroelectric Materials

Abstract

Since the discovery of ferroelectricity in HfO2-based materials which are comparable to the complementary metal-oxide–semiconductor (CMOS) fabrication process—a negative capacitance effect in the HfO2-based materials has been actively studied. Owing to nonuniform polarization-switching (which is originated from the polycrystalline structures of HfO2-based ferroelectric materials), the formation of multi-domains in the HfO2-based materials is inevitable. In previous studies, perovskite-based ferroelectric materials (which is not compatible to CMOS fabrication process) were utilized to improve the electrical properties of a nanoelectromechanical (NEM) relay. In this study, the effects of a multi-domain HfO2-based ferroelectric material on the electrical characteristics of an NEM relay were theoretically examined. Specifically, the number of domains, domain inhomogeneity and ferroelectric thickness of the multi-domain ferroelectric material were modulated and subsequently, its corresponding results were discussed. It was observed that the switching voltage variation was decreased with increasing the number of domains and decreasing domain inhomogeneity. In addition, the switching voltage was decreased with increasing ferroelectric thickness, owing to enhanced voltage amplification.