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This paper is a continuation and extension of our earlier work ( X-ray Spectrom. 2010, 39, 127-134, DOI:10.1002/xrs.1215) on the development of a software platform CATGIXRF, as a solution to provide non-destructive evaluation of nanostructured materials. Here, we describe an interactive graphical user interface (GUI) for the CATGIXRF program. The newly developed GUI interface facilitates determination of microstructural parameters on angstrom length scale for the nanostructured thin layered materials using synchrotron as well as laboratory X-ray sources. It allows combined analysis capabilities for both the X-ray reflectivity and grazing incidence X-ray fluorescence (GIXRF) data simultaneously, thus enabling us a greater sensitivity for the determination of microstructural parameters such as thickness, interface mixing, and roughness of a thin film medium with improved accuracies. The utility and various newly added salient features of the GUI-CATGIXRF program are described by providing example calculations as well as by analyzing experimentally a few thin film structures with different surface-interface properties. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this work, sol–gel ZnO thin films were implanted with Al ions of various fluences to study their electrical transport properties as transparent conducting oxide (TCO) layers. Additionally, formation of structural defects and modifications of the optical emission properties due to implantation have been investigated extensively to correlate the resultant electrical properties. By varying the ion fluence over two orders of magnitude from 1 × 1013 to 6 × 1015 ions/cm2, interestingly the electrical transport properties have been seen to be degraded in an unexpected manner as soon as Al is implanted and beyond a certain fluence (5 × 1013 ions/cm2), the electrical properties begin to improve. For the highest fluence (6 × 1015 ions/cm2), the sheet resistance is found to be 156 Ω/sq with an average visible transmission of 82%. The figure of merit value of our Al implanted ZnO film for an Al fluence of 5 × 1015 ions/cm2 is the highest till date, which may be prospective as a TCO layer. Detailed investigation on the evolution of the electrical and photoluminescence properties with an increase in the Al ion fluence reveals that zinc vacancy type defects are formed in large number which on healing produces further higher conductivity in the films. Image 1 • Sol-gel ZnO thin films were implanted with Al ions followed by annealing at 450 °C. • Film with 156 Ω/sq sheet resistance and >80% visible transmittance is produced. • Maximum FOM value of 9.57 × 10 −4 Ω −1 has been achieved. • Zinc vacancy plays a vital role in controlling the observed electrical properties. • The study is useful for understanding implantation effect and utilization of films as TCO. [ABSTRACT FROM AUTHOR]

Kirkendall effect has played an important role in developing the understanding of atomic diffusion and mass transport in solids. In thin films and multilayers, in which the microstructure may be far from thermal equilibrium, behavior of a system can be very different from that of the bulk. Therefore, there is a great need to understand the peculiarities of Kirkendall shift occurring at nanometer or sub-nanometer length scale in such systems. In the present work, Kirkendall shift in thin films has been measured with sub-nanometer accuracy, by making use of x-ray planar waveguide structures. Using this technique, we report an apparently counterintuitive result of Kirkendall shift associated with self-diffusion in nanocrystalline iron. The cavity of the waveguide consists of two layers of iron having different microstructures, separated by a thin marker layer of Ag. Thermal annealing results in shift of the Ag marker towards the Fe layer having a coarser grain structure. The effect is established unambiguously by studying two samples with the order of the two Fe layers reversed, and a third sample with the two Fe layers having the same microstructure. The result can be understood in terms of the difference in the microstructure of the two Fe layers; difference in the grain size and hence different concentration of the grain boundaries in the two layers results in a net mass transfer from one region to the other. [Display omitted] [ABSTRACT FROM AUTHOR]

The compositional profile and local atomic structure in a Co 40 Fe 40 B 20 thin film sandwiched between two W layers, have been probed combining time-of-flight secondary ion mass spectrometry (ToF-SIMS) and x-ray absorption fine structure spectroscopy techniques in standing wave geometry (SW-XAFS). The data analysis demonstrated inhomogeneities in the composition profile as well as in the local atomic structure around transition metals, along the film thickness. Boron concentration shows a gradual increase from the bottom to the surface of the film The quantitative analysis of the Fe and Co K edges SW-XAFS spectra reveals distinct differences in the local coordination geometry along the film thickness and between the two metals. Specifically, the local structure around Fe appeared to be more disordered on average compared to Co and the bond lengths exhibited significant variation as a function of depth, • SW-XAFS, XRR and TOF-SIMS were used to investigate the local atomic structure in W/Co 40 Fe 40 B 20 /W thin films. • SW-XAFS data show significant differences around Fe and Co, particularly for the Fe-B distribution. • The data analysis describes significant differences in the local coordination of Fe and Co in the film center with respect to the borders. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anomalous magnetic behavior is observed in Fe/Alq 3 bilayer. • Fe diffuses into Alq 3 to form 50 Å thick alloy layer at the interface. • Unexpected large effective magnetic dead layer is found at the interface. • Antiferromagnetic coupling between metallic Fe and alloyed Fe. Growth behavior and evolution of magnetism as a function of Fe thin film thickness onto organic semiconductor tris(8-hydroxyquinoline)-aluminum, (Alq 3) thin film was investigated in-situ using electrical resistance and magneto-optic Kerr effect (MOKE) measurements, respectively. The variation of electrical resistance with Fe film thickness reveals the Volmer-Weber growth of Fe on Alq 3 film. Reflection high energy electron diffraction (RHEED) pattern resembles polycrystalline BCC structure of Fe. Ex-situ x-ray reflectivity (XRR) measurement from the Fe/Alq 3 /Si sample reveals that Fe diffuses into Alq 3 to form an alloy layer of 50 Å thickness with Fe volume fraction of 0.4. In-situ MOKE study affirms anomalous magnetic behavior at the initial stage of Fe growth. Initially hysteresis loop appears and develops in a particular direction, and then vanishes at certain thickness. With further growth of Fe hysteresis loop appears again and grows in the opposite direction. The observed unusual changes in magnetic behavior as a function of Fe thickness may be explained in terms of the contribution from the magnetic Fe-Alq 3 alloy present in the intermix layer, the metallic Fe on top of Alq 3 layer, and their antiferromagnetic coupling. [ABSTRACT FROM AUTHOR]