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Periodic poling in titanium indiffused lithium niobate by direct electron beam irradiation is reported in this paper and the benefits the technique of X-ray diffraction (XRD) as a method to examine the structure of ferroelectric domains is presented. It is shown that in the case of periodically poled crystals with a grating period lower or equal than a few microns, XRD enables to straightforwardly access the domain inverted grating period. The use of analytical functions to model the XRD profiles allows this method to be easily implemented for on line non-destructive characterization of the devices.

The use of thin films of ferroelectric materials as a non-linear dielectric at microwave frequencies and the integration of tunable dielectrics are actively being investigated for a variety of advanced high frequency applications. This paper is devoted to the elaboration of Ba 1 m x Sr x TiO 3 (BST) thin films by the pulsed laser deposition technique. The microstructure of the films is investigated by high resolution X-ray diffraction. A cavity resonator technique is used to determine the relative dielectric permittivity of the BST layers.

Layered bismuth-containing perovskites are known to be subject to complex structural imperfections such as planar faults. A careful analysis of X-ray powder diffraction lines of the Aurivillius compound SrBi2Nb2O9 shows that stacking faults are located along the c axis and (hk0) reflections are thus unaffected by faulting. In the [001] direction the profiles exhibit a Lorentzian shape and a 22 nm coherently diffracting domain size is found, which corresponds to a stacking-fault density of 0.032 nm−1. The reciprocal-space mapping technique applied to epitaxial layers allows direct visualization of the highly anisotropic (001) reciprocal-lattice points. Because of the high counting rates and the lack of peak overlap in epitaxial layers, very subtle changes in the diffraction profiles can be measured as a function of thermal treatment time. Thermal annealing at 700°C up to 600 h reduces the stacking-fault density as attested by the strong increase in the domain size (198nm) and the broadening of the...