In-Situ Observation of The Initial Stages of Co (0001) Epitaxy on Pt (111) Using Grazing Incidence X-Ray Diffraction

1993 ◽  
Vol 312 ◽  
Author(s):  
James A. Bain ◽  
Bruce M. Clemens ◽  
Sean Brennan
Keyword(s):  
Early Stage ◽  
Stacking Faults ◽  
Grazing Incidence ◽  
In Situ Observation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Incoherent Interface ◽  
X Ray Scattering ◽  
Fault Density

AbstractThe heteropitaxial growth of (111) Pt on (0001) sapphire and of (0001) Co on (111) Pt on (0001) sapphire has been observed in-situ using grazing incidence x-ray scattering (GIXS). The in-plane lattice parameters of the Pt and Co phases have been measured as a function of film thickness in the regime from two monolayers to 200 monolayers, Relaxation of elastic strain with thickness has been quantified. X-ray reflections consistent with stacking faults in the Co films have been observed and monitored as a function of thickness, giving a measure of the stacking fault density. A distinct Co phase was observed at two monolayers of Co on a thick Pt layer, indicating an incoherent interface between the Co and Pt, even at this very early stage of deposition.

scholarly journals In Situ Investigation of the Early-Stage Growth of Nanoporous Alumina

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Thérèse Gorisse ◽  
Ludovic Dupré ◽  
Marc Zelsmann ◽  
Alina Vlad ◽  
Alessandro Coati ◽  
...  
Keyword(s):  
Early Stage ◽  
Grazing Incidence ◽  
Alumina Layer ◽  
Nanoporous Alumina ◽  
X Ray ◽  
X Ray Scattering ◽  
In Situ Investigation ◽  
Low X ◽  
X Ray Absorption

We report the successful use of in situ grazing incidence small-angle X-ray scattering to follow the anodization of aluminum. A dedicated electrochemical cell was designed and developed for this purpose with low X-ray absorption, with the possibility to access all azimuthal angles (360°) and to remotely control the temperature of the electrolyte. Three well-known fabrication techniques of nanoporous alumina, i.e., single, double, and pretextured, were investigated. The differences in the evolution of the scattering images are described and explained. From these measurements, we could determine at which moment the pores start growing even for very short anodization times. Furthermore, we could follow the thickness of the alumina layer as a function of the anodization time by monitoring the period of the Kiessig fringes. This work is aimed at helping to understand the different steps taking place during the anodization of aluminum at the very early stages of nanoporous alumina formation.

In Situ Synchrotron SAXS/WAXD Study during Uniaxial Drawing of Poly (L-Lactic Acid)

2014 ◽  
Vol 1048 ◽  
pp. 404-409
Author(s):  
Takahiko Kawai ◽  
Shin-ichi Kuroda
Keyword(s):  
Lactic Acid ◽  
Mechanical Response ◽  
Early Stage ◽  
Amorphous Film ◽  
X Ray Diffraction ◽  
X Ray ◽  
Saxs Measurement ◽  
X Ray Scattering ◽  
Shish Structure

The structure development of poly (L-lactic acid)(PLLA) during the uniaxial drawing was investigated by means of in-situ simultaneous wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) measurements. When the quenched amorphous film of PLLA was drawn at 77.2 oC, which was well above the glass transition temperature of PLLA, two different crystal structures were formed depending on the strain. The mesophase, which has 103 helix with large amount of packing disorder, was formed at the early stage of drawing, followed by the crystal transformation into α’ form (ε ≥ 1.5). SAXS measurement showed that the kebab formation begins at the stage later than that of meso-α’ transition. It strongly suggests that the transition takes place inside the shish structure. The development of kebab leads to the enhancement of mechanical response, which is found to be the origin of the strain hardening of PLLA.

scholarly journals Structure of a monolayer of molecular rotors on aqueous subphase from grazing-incidence X-ray diffraction

2018 ◽  
Vol 115 (38) ◽  
pp. 9373-9378 ◽  
Author(s):  
Jiří Kaleta ◽  
Jin Wen ◽  
Thomas F. Magnera ◽  
Paul I. Dron ◽  
Chenhui Zhu ◽  
...  
Keyword(s):  
Grazing Incidence ◽  
Molecular Rotors ◽  
Triangular Grid ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aqueous Subphase ◽  
Preparation Conditions ◽  
X Ray Scattering ◽  
A Minor

In situ grazing-incidence X-ray scattering shows that a monolayer of artificial rod-shaped dipolar molecular rotors produced on the surface of an aqueous subphase in a Langmuir trough has a structure conducive to a 2D ferroelectric phase. The axes of the rotors stand an average of 0.83 nm apart in a triangular grid, perpendicular to the surface within experimental error. They carry 2,3-dichlorophenylene rotators near rod centers, between two decks of interlocked triptycenes installed axially on the rotor axle. The analysis is based first on simultaneous fitting of observed Bragg rods and second on fitting the reflectivity curve with only three adjustable parameters and the calculated rotor electron density, which also revealed the presence of about seven molecules of water near each rotator. Dependent on preparation conditions, a minor and variable amount of a different crystal phase may also be present in the monolayer.

In situ observation of superstructures on InP(0 0 1) surface under hydrogen atmospheric environment with using grazing incidence X-ray diffraction

2000 ◽  
Vol 221 (1-4) ◽  
pp. 106-110 ◽  
Author(s):  
T Kawamura ◽  
Y Watanabe ◽  
Y Utsumi ◽  
K Uwai ◽  
J Matsui ◽  
...  
Keyword(s):  
Grazing Incidence ◽  
Atmospheric Environment ◽  
In Situ Observation ◽  
X Ray Diffraction ◽  
X Ray

New designs of hydrophobic and mesostructured Ultra Low k materials with isolated mesopores

2011 ◽  
Vol 1335 ◽  
Author(s):  
Anthony Grunenwald ◽  
André Ayral ◽  
Pierre Antoine Albouy ◽  
Vincent Rouessac ◽  
David Jauffres ◽  
...  
Keyword(s):  
Grazing Incidence ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
X Ray ◽  
In Situ Xrd ◽  
X Ray Scattering ◽  
Face Centered ◽  
Film Porosity ◽  
Low K

ABSTRACTIn this work, hydrophobic mesostructured organosilica thin films, exhibiting isolated mesopores (~ 7 nm), have been successfully deposited by spin-coating using different polystyrene-block-polyethylene oxide copolymers (PS-b-PEO) as structure-directing agents and methyltriethoxysilane (MTES) as organosilica precursor. Different ordered mesostructures (Face Centered Cubic, 2D or 3D Hexagonal and Body Centered Cubic) can be achieved by controlling different synthesis parameters. X-Ray Diffraction (XRD) and Grazing Incidence Small Angle X-Ray Scattering (GISAXS) techniques were used to investigate the mesostructure evolution through thermal and UV treatments. Swelling and shrinkage were evidenced by in-situ XRD and X-Ray Reflectivity measurements during the thermal removal of the meso-templates. Infrared spectroscopy and 29Si NMR were additionally used to investigate the microstructure evolution. The film porosity was estimated thanks to Ellipsometry Porosimetry (EP). Correlation between mechanical properties through nanoindentation measurements and the mesostructure ordering is discussed as well as assessments of the dielectric constant k by mercury contact probe.

Structural Characterization of Multilayers Using X-ray Diffraction

1991 ◽  
Vol 239 ◽  
Author(s):  
B. M. Clemens ◽  
J-A. Bain ◽  
A. P. Payne ◽  
T. C. Hufnagel ◽  
S. M. Brennan
Keyword(s):  
Grazing Incidence ◽  
Sputter Deposition ◽  
X Ray Diffraction ◽  
Deposition Pressure ◽  
X Ray ◽  
X Ray Scattering ◽  
Multilayered Materials ◽  
Cr System

ABSTRACTStructural deviations from ideal layering of bulk constituents can have dramatic effects on the properties of multilayered materials. We discuss three examples of the use of x-ray diffraction in non-standard geometries to examine these effects. In Mo/Ni multilayers, we use asymmetric diffraction and grazing incidence x-ray scattering (GIXS) to deduce the strain and intermixing. We find that coherency stresses between the BCC Mo and FCC Ni planes play a major role. In the Fe/Cr system, we use rocking curves and asymmetric scans about the small angle superlattice lines to investigate the nature and extent of layer roughness. We find that conformai roughness dominates our best samples, while non-conformal roughness increases with sputter deposition pressure. In the Gd/Co system, we use in-situ GIXS to investigate amorphization reaction during deposition. We find a strong diffusional asymmetry and rapid reaction during growth.

scholarly journals TheIn situgrowth of Nanostructures on Surfaces (INS) endstation of the ESRF BM32 beamline: a combined UHV–CVD and MBE reactor forin situX-ray scattering investigations of growing nanoparticles and semiconductor nanowires

2015 ◽  
Vol 22 (3) ◽  
pp. 688-700 ◽  
Author(s):  
V. Cantelli ◽  
O. Geaymond ◽  
O. Ulrich ◽  
T. Zhou ◽  
N. Blanc ◽  
...  
Keyword(s):  
Silicon Nanowires ◽  
Grazing Incidence ◽  
High Energy ◽  
Semiconductor Nanowires ◽  
Gas Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

This paper presents the upgraded `In situ growth of Nanoscructures on Surfaces' (INS) endstation of the InterFace beamline IF-BM32 at the European Synchrotron Radiation Facility (ESRF). This instrument, originally designed to investigate the structure of clean surfaces/interfaces/thin-films by surface X-ray diffraction, has been further developed to investigate the formation and evolution of nanostructures by combining small- and wide-angle X-ray scattering methodologies,i.e.grazing-incidence small-angle X-ray scattering (GISAXS) and grazing-incidence X-ray diffraction (GIXD). It consists of a UHV chamber mounted on az-axis type goniometer, equipped with residual gas analysis, reflection high-energy electron diffraction (RHEED) and Auger electron spectroscopy (AES) to complete the X-ray scattering investigations. The chamber has been developed so as up to eight sources of molecular beam epitaxy (MBE) can be simultaneously mounted to elaborate the nanostructures. A chemical vapor deposition (CVD) set-up has been added to expand the range of growing possibilities, in particular to investigatein situthe growth of semiconductor nanowires. This setup is presented in some detail, as well as the firstin situX-ray scattering measurements during the growth of silicon nanowires.

New Structure of CTAB Templated Silica Films as revealed by GISAXS coupled to HRTEM

2000 ◽  
Vol 628 ◽  
Author(s):  
Sophie Besson ◽  
Catherine Jacquiod ◽  
Thierry Gacoin ◽  
André Naudon ◽  
Christian Ricolleau ◽  
...  
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Grazing Incidence ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
Silica Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Hexagonal Arrangement ◽  
Spherical Micelles

ABSTRACTA microstructural study on surfactant templated silica films is performed by coupling traditional X-Ray Diffraction (XRD) and Transmission Electronic Microscopy (TEM) to Grazing Incidence Small Angle X-Ray Scattering (GISAXS). By this method it is shown that spin-coating of silicate solutions with cationic surfactant cetyltrimethylammonium bromide (CTAB) as a templating agent provides 3D hexagonal structure (space group P63/mmc) that is no longer compatible with the often described hexagonal arrangement of tubular micelles but rather with an hexagonal arrangement of spherical micelles. The extent of the hexagonal ordering and the texture can be optimized in films by varying the composition of the solution.

Sign in / Sign up

Export Citation Format

Share Document