Short-Range Order in Amorphous and Crystalline Ferroelectric [Hf.sub.0.5][Zr.sub.0.5][O.sub.2]

The microstructures of amorphous and polycrystalline ferroelectric [Hf.sub.0.5][Zr.sub.0.5][O.sub.2] films are studied by X-ray spectroscopy and ellipsometry. EXAFS spectra demonstrate that the amorphous film consists of an "incompletely mixed" solid solution of metallic oxides Hf[O.sub.2] and Zr[O.sub.2]. After rapid thermal annealing, the mixed [Hf.sub.0.5][Zr.sub.0.5][O.sub.2] oxide films have a more ordered polycrystalline structure, and individual Hf and Zr monoxide islands are formed in the films. These islands are several nanometers in size and have a structure that is similar to the monoclinic structure of Hf[O.sub.2] and Zr[O.sub.2]. The presence of the Hf[O.sub.2] and Zr[O.sub.2] phases in the [Hf.sub.0.5][Zr.sub.0.5][O.sub.2] films is also detected by ellipsometry.