Papers by Keyword: Electron Backscatter Diffraction (EBSD)

Abstract: In the present paper we report the texture and microstructure dependence of electromigration damage in Cu interconnects. This was made possible by ncorporating a sophisticated set of instrumentation within the SEM which enabled in-situ monitoring of the electromigration defects. The electron backscatter diffraction (EBSD) maps were obtained before and after the completion of the electromigration tests. Thus, by comparing the maps before and after the failure it was possible to associate the texture and microstructure with both failure sites - voids and hillocks. Results from lines down to 130 nm are included and orientation dependence of the defects is discussed.

Abstract: The crystallographic relationship between the g and a phases in samples of the Gibeon meteorite and a TRIP steel was investigated by means of EBSD techniques. The orientations of the two phases were measured and are represented in pole figures. The results are compared to predictions made on the basis of the Bain, Kurdjumov-Sachs (K-S), Nishiyama-Wassermann (NW), Greninger-Troiano (G-T) and Pitsch orientation relationships. The local misorientation between individual fcc and bcc crystals along their common interface was measured to demonstrate the way in which the exact orientation relationship varies along the boundary. The local orientations within lamellae and laths of kamacite and bainite are compared to that in recrystallised ferrite polygons. The occurrence of variant selection during the transformation of deformed austenite is analyzed using a recent dislocation-based model.

Abstract: The orientation distributions of α-Al2O3 textured ceramics are determined from neutron diffraction and SEM-EBSD. A curved position-sensitive detector coupled to a tilt angle (χ) scan allowed the whole neutron diffraction pattern treatment in the combined Rietveld-WIMV-Popa algorithm. Analyses from neutron and electron diffraction data gave similar results if EBSD data are smoothed to account for grain statistics. Four textured alumina ceramics were prepared by slipcasting under a high magnetic field and sintered at 800°C, 1300°C, 1400°C and 1600°C. The inverse pole figures and EBSD-mapping highlights the influence of the magnetic field and sintering temperature on the texture development. The inverse pole figures calculated for the fiber direction show a major (001) component for all the samples. With the increasing sintering temperature, the texture strength is enhanced and the c-axis distribution is sharper. The effectiveness of the combined approach for determining the crystallite size is also evident. As a global trend, the calculated crystallite size and observed grain size are similar and increase with the increasing sintering temperature. The mechanism of the texture development in the sintered specimens is certainly initiated from the preferred orientation of the green body after slip-casting under a high magnetic field. The basal texture is enhanced during sintering by selective anisotropic grain growth. We evidenced here the powerfulness of the Rietveld texture analysis correlated to SEM-EBSD calculation to provide a basis for the correlation of texture, microstructural parameters and anisotropic properties.

Abstract: Textural changes of Cu interconnects having a different line width were investigated after annealing. Texture was measured by XRD (x-ray diffraction) at different depth of the interconnect line and on the surface of interconnects using EBSD (electron backscattered diffraction) techniques. To analyze the relationship between the stress distribution and textural evolution observed in the different samples, the stresses were calculated for the different line width at 200°C using FEM (finite element modeling) along the width and depth of the line. In this investigation, it was found that the inhomogeneity of stress distribution in Cu interconnects is an important factor necessary for understanding textural transformation during annealing. Textural evolution in damascene interconnects lines during annealing is discussed, based on the state of stress in Cu electrodeposits.

Abstract: Free-standing CVD diamond films were prepared under the substrate temperature in the range of 850-1050oC. Macro- and micro-textures of the films were investigated based on the SEM observation as well as on the ODF and EBSD analysis. It was found that certain growth selection process appeared during diamond deposition which, however, did not lead to a strong film texture. It is indicated that strong fluctuation of growth ratio V<100>/V<111> and frequent growth twinning during film deposition resulted in randomization effect of grain orientations, which can be transformed by adjusting the parameters of film preparation.

Abstract: YBa2Cu3O7-δ ("YBCO") is a high-temperature ceramic superconductor. Due to its complex layered structure, a strong biaxial texture of the YBCO grains is necessary to achieve technically relevant currents. In this paper, we describe the development of flexible metallic tapes with strong cube texture, providing a lattice-matched template for buffer and YBCO coatings in proper orientation. Texture analysis was performed using electron backscatter diffraction (EBSD).

Abstract: Ni with columnar grain was cold rolled and then recrystallized. The orientations at triple junctions before and after annealing were characterised using the EBSD technique, and recrystallization nuclei at triple junctions were identified. A comparison was made between the orientations of the nuclei and the orientations of the grains in the same area before annealing. Both nuclei with orientations within the orientation spread of the deformed grains as well as away from that were found.

Abstract: The first steps of recovery and recrystallization in an IF-Ti steel after 35% deformation by uniaxial tension have been studied by Electron Back Scattered Diffraction (EBSD), Orientation Imaging Microscopy(™) (OIM) and Transmission Electron Microscopy (TEM). Two types of substructure are created after tensile strain: diamond shaped cells for the {111}<110> component and equiaxed cells for {001}<110> component. The recovery is by the decrease of dislocation density inside cells, the refinement of the cell walls, the vanishing of the cell wall, the cell coalescence and the cell growth. Recrystallized grains developed by two main recrystallization mechanisms: the “generalized recovery” and the “bulging”. Both mechanisms are based on continuous growth of subgrains followed or not by the migration of the prior grain boundaries.

Abstract: The stored energy of two cold rolled IF-Ti steels is calculated using finite element method from an EBSD microstructure. Because the thermo-mechanical treatments are different for the two materials, the parameters of the behaviour law used in the simulation and identified using a polycrystalline model and an inverse method from experimental results are also different. Their variation is due to the number of experimental tests taken into account for their identification and obviously to the thermo-mechanical path. The stored energy is mainly influenced by Lu which represents the mean free path of the mobile dislocations gliding on the system u and which is expressed as a function of a K material parameter. Using one tension test, the experimental stored energy values estimated from neutron diffraction measurements can be reproduced only for a material parameter K fixed.