title: Dielectric relaxation of high-k oxides.
abstract: Frequency dispersion of high-k dielectrics was observed and classified into two parts: extrinsic cause and intrinsic cause. Frequency dependence of dielectric constant (dielectric relaxation), that is the intrinsic frequency dispersion, could not be characterized before considering the effects of extrinsic frequency dispersion. Several mathematical models were discussed to describe the dielectric relaxation of high-k dielectrics. For the physical mechanism, dielectric relaxation was found to be related to the degree of polarization, which depended on the structure of the high-k material. It was attributed to the enhancement of the correlations among polar nanodomain. The effect of grain size for the high-k materials' structure mainly originated from higher surface stress in smaller grain due to its higher concentration of grain boundary.
authors.forename: Chun
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, UK. cezhou.zhao@xjtlu.edu.cn.
authors.forename: Ce Zhou
authors.initials: CZ
authors.lastname: Zhao
authors.forename: Matthew
authors.initials: M
authors.lastname: Werner
authors.forename: Steve
authors.initials: S
authors.lastname: Taylor
authors.forename: Paul
authors.initials: P
authors.lastname: Chalker