Comparison of Paraelectric and Ferroelectric Materials for Applications as Dielectrics in Thin Film Integrated Capacitors

摘要

Ferroelectrics such as BaTiO_3 and Ba_x Sr_1-x TiO_3 can exhibit dielectric constants up to three orders of magnitude higher than those of paraelectric materials such as SiO_2, Al_2O_3, Ta_2O_5, and BCB. However, the dielectric properties of ferroelectrics are typically a stronger function of temperature, frequency, film thickness, and bias resulting in significant nonlinearities in their perfor- mance. Also, the dielectric constant of some ferroelectrics degrades with time.