X-ray double-crystal diffractometry of Verneuil-grown SrTiO3 crystals

Using a double-crystal arrangement of nearly parallel setting, X-ray Bragg- case diffraction curves were measured for (100) and (110) surfaces of SrTiO 3 crystals. grown by the Verneuil method and used widely as a substrate for fabricating electronic thin film devices. The peak height and half-width o f rocking curves (200 and 220 reflections. Cu K alpha (1)) measured from lo cal areas of samples varied over a wide range with the samples and probed a reas. presumably due to the effect of dislocations and other imperfections. A certain proportion of the measured curves was in fair agreement with the theoretical Curve for a perfect crystal. being only 1-2 arcsec broader in half-width. The local-area rocking curve measurement provides like this use ful information on the perfection characterization of SrTiO3 crystals. The measurement shows that mechanochemically polished surfaces of the sample cr ystals are significantly free of polishing strain in both the (100) and (11 0) samples, while the assessment of the bulk-crystal perfection by the expe rimental results needs a discussion. Rocking curves were also measured from the entire surface of the sample crystals to obtain an evaluation of overa ll misorientaion.