Preparation of metal–organic decomposition-derived strontium zirconate dielectric thin films

Abstract

Metal–organic decomposition-derived SrZrO 3 dielectric thin films were investigated using differential thermal analysis, thermogravimetric analysis, X-ray diffraction, Fourier transform infrared reflectivity spectroscopy and atomic force microscopy to study the mechanism of phase transformation and crystallinity, and were characterized by electric and dielectric properties as well. The phase transformation and crystallinity results show that the film has amorphous structure with carbonate existing when annealed at 550 °C; while when annealed at 600 °C and above, the carbonate is decomposed and those films crystallize into perovskite phase without preferred orientation. In addition, the electric properties show these films exhibit very low leakage current density and high breakdown strength. Typically, the film annealed at 600 °C has the lowest leakage current density of 4.2×10 −10 A cm −2 at the field strength of 580 kV cm −1 and the breakdown strength is close to 1.3 MV cm −1. Moreover, the dielectric properties show that, at room temperature, these films have their dielectric constants higher than 22.0 with very little dispersion in a frequency range from 100 Hz to 1 MHz and are nearly independent of applied dc bias.