International audienceThe misorientations induced by cold-rolling in commercially pure titanium by twinning and multiple twinning were investigated by electron backscatter diffraction. Three main types of twins occur: compressive twins (64.6° 1 00) which are predominant, followed by tensile twins of type 1 (84.8° [11 0]) and a few of type 2 (35.1° 1 00). The main multiple twinning configurations are (i) several variants of a given type of twin inside a given grain and (ii) second-generation tensile twins inside primary compressive twins. All possible misorientations resulting from the combination of two out of the three main twinning systems have been calculated and compared with the experimentally observed twin configurations. This facilitated interpretation of the peak found at 41° 5 3 in the misorientation distribution as the result of double twinning (tensile twins inside primary compressive twins)

Electron backscatter diffraction (EBSD) has become a common technique for measuring crystallographic orientations at spatial resolutions on the order of tens of nanometers and at angular resolutions <0.1°. In a recent search of EBSD papers using Google Scholar™, 60% were found to address some aspect of deformation. Generally, deformation manifests itself in EBSD measurements by small local misorientations. An increase in the local misorientation is often observed near grain boundaries in deformed microstructures. This may be indicative of dislocation pile-up at the boundaries but could also be due to a loss of orientation precision in the EBSD measurements. When the electron beam is positioned at or near a grain boundary, the diffraction volume contains the crystal lattices from the two grains separated by the boundary. Thus, the resulting pattern will contain contributions from both lattices. Such mixed patterns can pose some challenge to the EBSD pattern band detection and indexing algorithms. Through analysis of experimental local misorientation data and simulated pattern mixing, this work shows that some of the rise in local misorientation is an artifact due to the mixed patterns at the boundary but that the rise due to physical phenomena is also observed.

The ex situ lift out (EXLO) adhesion forces are reviewed and new applications of EXLO for focused ion beam (FIB)-prepared specimens are described. EXLO is used to manipulate electron transparent specimens on microelectromechanical systems carrier devices designed for in situ electron microscope analysis. A new patented grid design without a support film is described for EXLO. This new slotted grid design provides a surface for holding the specimen in place and also allows for post lift out processing. Specimens may be easily manipulated into a backside orientation to reduce FIB curtaining artifacts with this slotted grid. Large EXLO specimens can be manipulated from Xe+ plasma FIB prepared specimens. Finally, applications of EXLO and manipulation of FIB specimens using a vacuum probe lift out method are shown. The vacuum probe provides more control for placing specimens on the new slotted grids and also allows for easy manipulation into a backside configuration.

Copper films were electroplated on either W/TiN/Si(100) or Cu/TaN/Si(100) surfaces with copper electrolytes containing different types of acids, namely, H2SO4, HCl, HNO3, and HF. The properties of these copper films were then characterized in terms of their microstructure and electrical properties. Dense copper films were obtained from H2SO4 and HNO3-based electrolytes, which produced films consisting of small equiaxed grains with average grain sizes of 0.25 μm whereas larger grains of 0.5 μm were obtained from a HF-based electrolyte. However, a very rough Cu film with copper chloride residues was obtained from the HCl-based electrolyte. For W seeded substrates, strong 〈111〉 oriented copper films were produced while both 〈111〉 and 〈220〉 were observed as the preferred orientations of the film on Cu seeded substrates. Both H2SO4- and HNO3-based electrolytes were able to produce films with bulk resistivity as low as 1.82 μΩ cm on Cu seeded substrates. For W seed, the bulk resistivity varied between 1.92 and 2.31 μΩ cm. The HF-based electrolyte produced the highest bulk resistivity of 2.23 μΩ cm. In terms of the deposition rate, both HNO3 and HF achieved higher deposition rates than H2SO4.

The effects of grain boundary character on the intergranular corrosion susceptibility of 2124 aluminum alloy were examined. In the study, the alloy was heat treated at 540ºC and corrosion tested according to ASTM G110 standards. After obtaining grain orientations from the automated Electron Back-Scatter Diffraction (EBSD), both grain boundary character and grain boundary plane distributions were analyzed. Results show that low-angle boundaries and boundaries with a sigma-3 or sigma-7 coincident site lattice relationship tend to have a higher corrosion resistance than other random boundaries.