Three dimensional reciprocal space measurement by x-ray diffraction using linear and area detectors: Applications to texture and defects determination in oriented thin films and nanoprecipitates

Abstract

The authors present a method for the fast and efficient measurement of volumes of reciprocal space by x-ray diffraction using linear and area detectors. The goal of this technique is to obtain a complete overview of the reciprocal space to detect and characterize the nature and orientation of all the phases present. They first explain the detailed procedures and scan strategies required for transforming raw scattering data into three-dimensional maps of reciprocal space and present a complete open-source software package for advanced data processing, analysis, and visualization. Several case studies, chosen to highlight the overall capabilities of the technique, are then introduced. First, thermal diffuse scattering from a monocrystalline Si substrate is characterized by the presence of lines linking diffraction peaks in reciprocal space. Second, a detailed investigation of texture in multiphase thin layers permits us to reveal the unambiguous presence of fiber, axiotaxial, and epitaxial components in oriented films. The visualization of a significant fraction of reciprocal space has allowed us to identify an unexpected metastable phase, which could not be deduced from measurements carried out in the Bragg–Brentano geometry. The technique is then used to study planar defects in nickel silicides formed by solid-state reactions and micro twins in a GaP matrix containing coherent MnP precipitates. Overall, the authors show that the systematic acquisition of significant volumes of reciprocal space permits us to observe behaviors that might otherwise remain undetected when analyses are restricted to typical measurement scans.

Determination of mosaicity in oriented stacks of lipid bilayers

“…Both methods indicate that the mosaic distribution has long tails, more consistent with a Lorentzian than a Gaussian, although the ring method indicates a tail that is somewhat shorter than a Lorentzian for our most extensively analyzed dry sample. As recent papers that determine pole figures emphasize 11–13 , such determinations are greatly facilitated by the use of area detectors. Compared to the traditional rocking scan, an advantage of analyzing a Bragg ring is that fewer exposures are required and the angular range is not limited (due to a non-transparent substrate) to the [0,2θ B ] range of rocking scans.…”

“…As the bilayers in each domain are in-plane powders and there is only one-dimensional stacking order, the only characterizing parameter for the mosaicity is the angle α between the mean normal to the stack and the normal to the substrate; this is simpler than the more complex pole figure characterization of general thin films consisting of crystallites. 11–13 …”

Reaction of Ni film with In0.53Ga0.47As: Phase formation and texture

“…Therefore, there have been intense investigations on silicide technology (e.g., TiSi 2 , CoSi 2 , and NiSi) 3 over more than 25 years, leading to fundamental understanding on the peculiar microstructure observed for these compounds obtained by the SSR. 4,5 On the contrary, the knowledge turns out to be limited when it comes to ohmic metal contacts on III-V materials for MOSFET applications. For such alloys, salicide-like technology has been recently developed and it has been found that the Ni-In x Ga 1-x As alloy is a promising material for the self-aligned metal source/drain (S/D) of In x Ga 1-x As n-MOSFETs.…”

Texture in thin film silicides and germanides: A review

“…Texture studies using pole figures or EBSD can provide conclusive information when identifying silicide/germanide phases formed during a solidstate reaction. This is especially the case when the formed phase exhibits strong epitaxial or fiber components, as standard h=2h XRD techniques provide limited information for such films 37 (see also Section II A). In this section, we will give an overview of studies that have investigated the influence of texture on silicide/germanide phase formation and properties.…”

“…31 In the following years, detailed texture studies of different silicide and germanide materials were carried out using this technique, revealing axiotaxy in a considerable number of silicide/germanide materials (see Table I). More recently, the use of a linear or area detector instead of a point detector 37,38 and the introduction of EBSD as a complementary technique 41 have enabled the ability to perform unambiguous phase identification of highly textured transient phases that form during the formation of NiSi 33,35 or NiGe 103 (see Section IV A). In the near future, area detectors will be routinely used to record texture information in situ, enabling the study of texture evolution during silicide/germanide formation.…”