Papers by Keyword: Crystal Properties

Abstract: Double perovskite Sr₂FeMoO₆ film with different thickness was prepared by electrophoresis method on single crystal Si substrate. The post-annealing treatment was carried out at 1100°C with 5% H₂/Ar flow. XRD result shows that all the films are of single phase and belong to the I4/m lattice. All the films have no preferred orientation and exhibit typical polycrystal property. Measurement on scanning electron microscope shows that all the three films exhibit similar surface morphology. Different from crystal structure and surface morphology, Curie temperature (T_C) shows a non-linear evolution with the thickness of the film. T_C of the film increases firstly and then decreases, the highest T_C is 300 K. This result indicates that ferromagnetism of the film is strengthened at the thickness about 35μm.

Abstract: Bilayer-type ZTO thin films were prepared by MOCVD, metal organic chemical vapor deposition. As the films were investigated with UV spectrophotometer, XRD, SEM and other modern research methods, the optics and crystal properties of the ZTO thin films were researched. From the analysis of testing results, visible light transmittance of ZnO/SnO2-type film was superior to SnO2/ZnO-type film, and ternary compound, Zn2SnO4, was found in the two kinds of bilayer-type films. The priority of nucleation should emerged between the (100) crystal plane of ZnO and the (110) crystal plane of SnO2.

Abstract: This article summarizes the work of the author’s lab based on crystallography. The topics are categorized in the following three fields: The first category is crystallographic analysis of materials, the second one is correlations between crystal structure and their properties, and the third one is crystallography for processing such as epitaxy, topotaxy and templates. The examples for these categories are: (1) multilayer ceramic capacitor (MLCC); (2) microwave dielectrics of tungstenbronze-type like solid solutions, and piezoelectric materials langasite (La3Ga5SiO14); (3) thin film growth of GaN or AlN on sapphire for example of epitaxy, hydroxy-apatite grown on diopside for topotaxy, and template growth of microwave dielectrics for template. Crystallography is useful in all studies, but is not almighty. Interdisciplinary study between crystallography and solid state physics is necessary to make clear the mechanism of the properties.