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Results for “coherent diffraction microscopy”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Physical properties of epitaxial ZrN/MgO(001) layers grown by reactive magnetron sputtering

Single-crystal ZrN films, 830 nm thick, are grown on MgO(001) at 450 °C by magnetically unbalanced reactive magnetron sputtering. The combination of high-resolution x-ray diffraction reciprocal lattice maps, high-resolution cross-sectional transmission electron microscopy, and selected-area electron diffraction shows that ZrN grows epitaxially on MgO(001) with a cube-on-cube orientational relationship, (001){sub ZrN}‖(001){sub MgO} and [100]{sub ZrN}‖[100]{sub MgO}. The layers are essentially fully relaxed with a lattice parameter of 0.4575 nm, in good agreement with reported results for bulk ZrN crystals. X-ray reflectivity results reveal that the films are completely dense with smooth surfaces (roughness = 1.3 nm, consistent with atomic-force microscopy analyses). Based on temperature-dependent electronic transport measurements, epitaxial ZrN/MgO(001) layers have a room-temperature resistivity ρ{sub 300K} of 12.0 μΩ-cm, a temperature coefficient of resistivity between 100 and 300 K of 5.6 × 10{sup −8}Ω-cm K{sup −1}, a residual resistivity ρ{sub o} below 30 K of 0.78 μΩ-cm (corresponding to a residual resistivity ratio ρ{sub 300Κ}/ρ{sub 15K} = 15), and the layers exhibit a superconducting transition temperature of 10.4 K. The relatively high residual resistivity ratio, combined with long in-plane and out-of-plane x-ray coherence lengths, ξ{sub ‖} = 18 nm and ξ{sub ⊥} = 161 nm, indicates high crystalline quality with low mosaicity. The reflectance of ZrN(001), as determined by variable-angle spectroscopic ellipsometry, decreases slowly from 95% at 1 eV to 90% at 2 eV with a reflectance edge at 3.04 eV. Interband transitions dominate the dielectric response above 2 eV. The ZrN(001) nanoindentation hardness and modulus are 22.7 ± 1.7 and 450 ± 25 GPa.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Quantitative agreement between dynamical rocking curves in ultrafast electron diffraction for x-ray lasers

Electron diffraction through a thin patterned silicon membrane can be used to create complex spatial modulations in electron distributions. By precisely varying parameters such as crystallographic orientation and wafer thickness, the intensity of reflections in the diffraction plane can be controlled and by placing an aperture to block all but one spot, we can form an image with different parts of the patterned membrane, as is done for bright-field imaging in microscopy. The patterned electron beams can then be used to control phase and amplitude of subsequent x-ray emission, enabling novel coherent x-ray methods. Furthermore, the electrons themselves can also be used for femtosecond time resolved diffraction and microscopy. As a first step toward patterned beams, we demonstrate experimentally and through simulation the ability to accurately predict and control diffraction spot intensities. We simulate MeV transmission electron diffraction patterns using the multislice method for various crystallographic orientations of a single crystal Si(001) membrane near beam normal. The resulting intensity maps of the Bragg reflections are compared to experimental results obtained at the Accelerator Structure Test Area Ultrafast Electron Diffraction (ASTA UED) facility at SLAC. Furthermore, the fraction of inelastic and elastic scattering of the initial charge is estimated along with the absorption of the membrane to determine the contrast that would be seen in a patterned version of the Si(001) membrane.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Structural Consequences of Ferroelectric Nanolithography

Domains of remnant polarization can be written into ferroelectrics with nanoscale precision using scanning probe nanolithography techniques such as piezoresponse force microscopy (PFM). Understanding the structural effects accompanying this process has been challenging due to the lack of appropriate structural characterization tools. Synchrotron X-ray nanodiffraction provides images of the domain structure written by PFM into an epitaxial Pb(Zr,Ti)O{sub 3} thin film and simultaneously reveals structural effects arising from the writing process. A coherent scattering simulation including the superposition of the beams simultaneously diffracted by multiple mosaic blocks provides an excellent fit to the observed diffraction patterns. Domains in which the polarization is reversed from the as-grown state have a strain of up to 0.1% representing the piezoelectric response to unscreened surface charges. An additional X-ray microdiffraction study of the photon-energy dependence of the difference in diffracted intensity between opposite polarization states shows that this contrast has a crystallographic origin. The sign and magnitude of the intensity contrast between domains of opposite polarization are consistent with the polarization expected from PFM images and with the writing of domains through the entire thickness of the ferroelectric layer. The strain induced by writing provides a significant additional contribution to the increased free energy of the written domain state with respect to a uniformly polarized state.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2010

Magnetite Nanoparticles Coated with Rifampicin and Chlortetracycline for Drug Delivery Applications

Four types of biocompatible magnetic fluids based on superparamagnetic nanoparticles with Fe{sub 3}O{sub 4} cores were functionalized with antibiotics (rifampicin or chlortetracycline) as potential candidates for in vivo biomedical applications, such as magnetically controlled drug delivery. The synthesis consisted in coprecipitation of iron oxide in basic, as well as in acid medium, followed by the dispersion of the resulted magnetite nanoparticles in aqueous solution containing the antibiotic. The chosen method to prepare the magnetite-core/drug-shell systems avoided intermediate organic coating of the magnetic nanoparticles. Comparative analysis of the rheological features of the aqueous magnetic fluid samples was performed. The structural features of the coated magnetic particles were investigated by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometry (VSM). Good crystallinity and adequate stability in time were evidenced. Drug delivery curves were spectrophotometrically provided.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2011

The origin of early age expansions induced in cementitious materials containing shrinkage reducing admixtures

Studies on the early-age shrinkage behavior of cement pastes, mortars, and concretes containing shrinkage reducing admixtures (SRAs) have indicated these mixtures frequently exhibit an expansion shortly after setting. While the magnitude of the expansion has been noted to be a function of the chemistry of the cement and the admixture dosage; the cause of the expansion is not clearly understood. This investigation uses measurements of autogenous deformation, X-ray diffraction, pore solution analysis, thermogravimetry, and scanning electron microscopy to study the early-age properties and describe the mechanism of the expansion in OPC pastes made with and without SRA. The composition of the pore solution indicates that the presence of the SRA increases the portlandite oversaturation level in solution which can result in higher crystallization stresses which could lead to an expansion. This observation is supported by deformation calculations for the systems examined.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Structure and mechanical properties of Al-3Fe rapidly solidified alloy

The Al based Al-3 wt%Fe alloy was prepared by conventionally casting (ingot) and further processed the melt-spinning technique and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) together with energy dispersive spectroscopy (EDS), differential scanning calorimetry (DSC) and the Vickers microhardness tester. The rapidly solidified (RS) binary alloys were composed of supersaturated {alpha}-Al solid solution and finely dispersed intermetallic phases. Experimental results showed that the mechanical properties of RS alloys were enhanced, which can be attributed to significant changes in the microstructure. The dependence of microhardness H{sub V} on the solidification rate (V) was analysed. These results showed that with the increasing values of V, the values of H{sub V} increased.

36 MATERIALS SCIENCE↗
DOE OSTI2011

A new ordered triple Hollandite: Ba{sub 1.33}Sb{sub 2.66}Al{sub 5.33}O{sub 16}

Ba{sub 1.33}Sb{sub 2.66}Al{sub 5.33}O{sub 16} is a triple Hollandite, which crystallizes in a tetragonal cell (I4/m no. 87) with a=b=9.86090(5) A and c=8.77612(6) A. Its crystal structure was characterized using electron diffraction and X-ray powder diffraction; it is isotypic to K{sub 1.33}Mg{sub 3.11}Sb{sub 4.89}O{sub 16}, K{sub 1.76}Mg{sub 3.25}Sb{sub 4.75}O{sub 16} and to K{sub 1.8}Li{sub 2.45}Sb{sub 5.55}O{sub 16}. In the rutile chains of Ba{sub 1.33}Sb{sub 2.66}Al{sub 5.33}O{sub 16}, the ordering of Al and Sb atoms into unmixed sites induces the tripling of the c parameter compared to a 'single' Hollandite structure. The Ba{sup 2+} cations are dispersed along c, in the largest tunnels on non-split and fully occupied sites. They lie into Ba-Ba pairs separated by vacancies. Their regular arrangement has been confirmed by high resolution electron microscopy. Electrochemical experiments have also been performed in Li-ion cell but no Li insertion was detected. - Graphical Abstract: The new Ba{sub 1.33}Sb{sub 2.66}Al{sub 5.33}O{sub 16} triple Hollandite has been synthesized and characterized by X-ray diffraction, electron microscopy, and cyclic voltammetry. Highlights: > Synthesis of a new barium antimonium aluminium oxide with a Hollandite structure. > X-ray diffraction, electron microscopy and cyclic voltammetry studies. > Presence of cationic vacancies but no Li insertion activity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2011

Synthesis and Characterization of Lead Calcium Titanate Nanocomposite

Lead calcium titanate nanoparticles (PCT-NPs) were synthesized by the modified sol-gel method. The mixed metal alkoxide precursor was prepared by moderate refluxing using lead acetate, calcium acetate, titanium iso-propoxide and 2-methoxyethanol. The properties of PCT-NPs were studied as a function of calcination temperatures. Results from the powder X-ray diffraction (XRD) and thermal analysis (TGA/DTA), indicated that the single-phase perovskite PCT-NPs were obtained after heat treatment at temperature of 700 deg. C. The average particle size of synthesized PCT-NPs was found to be around 30 nm from transition electron microscopy (TEM).

36 MATERIALS SCIENCE↗
DOE OSTI2012

Revisiting the properties of delafossite CuCrO{sub 2}: A single crystal study

Platelet-like single-crystals of delafossite CuCrO{sub 2} have been successfully grown and characterised by X-ray diffraction and pole figures, scanning electron and atomic force microscopy. Transport measurements reveal that the resistivity is highly anisotropic, with a ratio of about 35 at 300 K between the in- and out-of-plane directions, reflecting the layered crystal structure. The magnetization and specific heat data show that CuCrO{sub 2} undergoes a unique antiferromagnetic transition at T{sub N}=24.0 K, in contrast to a recent report on CuCrO{sub 2} single-crystals showing the existence of two magnetic transitions, T{sub N1}=24.2 K and T{sub N2}=23.6 K, depending on the orientation of the applied magnetic field along and perpendicular to c, respectively. - Graphical abstract: 3R-CuCrO{sub 2} platelet-like single crystals have been successfully grown by the flux method. As revealed by {chi}(T) and C(T) measurements, their properties are characterised by a unique antiferromagnetic transition at T{sub N}=24 K. Interestingly, despite a very small magnetic anisotropy, a large one is evidenced by the resistivity ratio, {rho}{sub c}/{rho}{sub ab}{approx}35, at 300 K. This suggests an easier charge hopping in the [CrO{sub 2}] planes rather than along (Cr-O-Cu) pathways, i.e. along c axis. Highlights: Black-Right-Pointing-Pointer R-CuCrO{sub 2} plate-like single crystals have been synthesised by the flux method. Black-Right-Pointing-Pointer Growth takes place layer-by-layer and some growth defects have been observed. Black-Right-Pointing-Pointer CuCrO{sub 2} single crystals exhibit a unique antiferromagnetic transition at T{sub N}=24 K. Black-Right-Pointing-Pointer Transport measurements reveal that the resistivity is highly anisotropic.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Ferritic Alloys with Extreme Creep Resistance via Coherent Hierarchical Precipitates

There have been numerous efforts to develop creep-resistant materials strengthened by incoherent particles at high temperatures and stresses in response to future energy needs for steam turbines in thermal-power plants. However, the microstructural instability of the incoherent-particle-strengthened ferritic steels limits their application to temperatures below 900 K. Here, we report a novel ferritic alloy with the excellent creep resistance enhanced by coherent hierarchical precipitates, using the integrated experimental (transmission-electron microscopy/scanning-transmission-electron microscopy, in-situ neutron diffraction, and atom-probe tomography) and theoretical (crystal-plasticity finite-element modeling) approaches. This alloy is strengthened by nano-scaled L21-Ni2TiAl (Heusler phase)-based precipitates, which themselves contain coherent nano-scaled B2 zones. These coherent hierarchical precipitates are uniformly distributed within the Fe matrix. Our hierarchical structure material exhibits the superior creep resistance at 973 K in terms of the minimal creep rate, which is four orders of magnitude lower than that of conventional ferritic steels. These results provide a new alloy-design strategy using the novel concept of hierarchical precipitates and the fundamental science for developing creep-resistant ferritic alloys. Finally, the present research will broaden the applications of ferritic alloys to higher temperatures.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Quantitative phase analysis and microstructure characterization of magnetite nanocrystals obtained by microwave assisted non-hydrolytic sol–gel synthesis

An innovative preparation procedure, based on microwave assisted non-hydrolytic sol–gel synthesis, to obtain spherical magnetite nanoparticles was reported together with a detailed quantitative phase analysis and microstructure characterization of the synthetic products. The nanoparticle growth was analyzed as a function of the synthesis time and was described in terms of crystallization degree employing the Rietveld method on the magnetic nanostructured system for the determination of the amorphous content using hematite as internal standard. Product crystallinity increases as the microwave thermal treatment is increased and reaches very high percentages for synthesis times longer than 1 h. Microstructural evolution of nanocrystals was followed by the integral breadth methods to obtain information on the crystallite size-strain distribution. The results of diffraction line profile analysis were compared with nanoparticle grain distribution estimated by dimensional analysis of the transmission electron microscopy (TEM) images. A variation both in the average grain size and in the distribution of the coherently diffraction domains is evidenced, allowing to suppose a relationship between the two quantities. The traditional integral breadth methods have proven to be valid for a rapid assessment of the diffraction line broadening effects in the above-mentioned nanostructured systems and the basic assumption for the correct use of these methods are discussed as well. - Highlights: • Fe{sub 3}O{sub 4} nanocrystals were obtained by MW-assisted non-hydrolytic sol–gel synthesis. • Quantitative phase analysis revealed that crystallinity up to 95% was reached. • The strategy of Rietveld refinements was discussed in details. • Dimensional analysis showed nanoparticles ranging from 4 to 8 nm. • Results of integral breadth methods were compared with microscopic analysis.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2011

Influence of EDTA{sup 2-} on the hydrothermal synthesis of CdTe nanocrystallites

Transformation from Te nanorods to CdTe nanoparticles was achieved with the assistance of EDTA as a ligand under hydrothermal conditions. Experimental results showed that at the beginning of reaction Te nucleated and grew into nanorods. With the proceeding of reaction, CdTe nucleus began to emerge on the surface, especially on the tips of Te nanorods. Finally, nearly monodispersed hexagonal CdTe nanoparticles with diameters of about 200 nm were obtained. The effects of EDTA on the morphology and formation of CdTe nanoparticles were discussed in consideration of the strong ligand-effect of EDTA, which greatly decreased the concentration of Cd{sup 2+}. Furthermore, the possible formation process of CdTe nanoparticles from Te nanorods was further proposed. The crystal structure and morphology of the products were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). - Graphical Abstract: Firstly, Te nucleated and grew into nanorods in the presence of EDTA{sup 2-}. Then CdTe nucleus began to emerge on Te nanorods and finally monodispersed CdTe nanoparticles were obtained. Highlights: Black-Right-Pointing-Pointer EDTA serves as a strong ligand with Cd{sup 2+}. Black-Right-Pointing-Pointer The existence of EDTA constrains the nucleation of CdTe and promotes the formation of Te nanorods. Black-Right-Pointing-Pointer With the proceeding of reaction, CdTe nucleus began to emerge on the surface, especially on the tips of Te nanorods. Black-Right-Pointing-Pointer Nearly monodispersed hexagonal CdTe nanoparticles with diameters of about 200 nm were finally obtained.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2010

Effect of microstructure on Au/sapphire interfacial thermal resistance

We deposit Au films on single crystal sapphire substrates by sputtering and evaporation methods. The microstructure characteristics such as crystal textures, grain sizes, and fraction of contacted area of the films are examined by x-ray diffraction and transmission electron microscopy. The sputtered films have an average grain size of about 200 nm and perfectly attach to the substrates; the as-evaporated films partially attach to the substrate; the grain size varies from 10 to 30 nm, and after annealing, increases to 50 nm. Au{sub 2}Al phase is observed in the annealed samples. The interfacial thermal resistance is measured by a frequency domain thermoreflectance method. The thermal resistance of the sputtered Au/sapphire interfaces is 35.5x10{sup -9} m{sup 2} K W{sup -1}, and those of the evaporated samples are up to three times as large as this value. The change in interfacial thermal resistance is explained by the effect of detachment using a parallel arranged thermal resistance model, the effect of grain size, and the influence of chemical bonding at the interfaces.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Thermoelectric and microstructural properties of Pb{sub 0.9-x}Sn{sub 0.1}Ge{sub x}Te compounds prepared by spinodal decomposition

Three samples of Pb{sub 0.9-x}Sn{sub 0.1}Ge{sub x}Te with x=0.25, 0.35, 0.6 were prepared by heating the mixtures above the melting point of the constituent elements followed by quenching in water. The x=0.6 sample is close to the center of the immiscibility region, while the x=0.25 and 0.35 samples are in the Pb rich region inside the spinodal miscibility gap. Microstructural investigations using Powder X-ray Diffraction, Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy revealed both GeTe-rich and PbTe-rich phases. The samples were uniaxially hot pressed and the thermoelectric properties were characterized in the temperature range 2-400 K using a commercial apparatus and from 300 to 650 K with a custom designed setup. The best sample (x=0.6) reached zT{approx}0.6 at 650 K, while the x=0.25 and 0.35 samples showed thermal instability at elevated temperatures. -- Graphical abstract: Spinodal decomposition in the GeTe-SnTe-PbTe system demonstrated by SEM and EXS images. Display Omitted Highlights: {yields} Investigation of Pb-rich part of the spinodal miscibility gap in PbTe-SnTe-GeTe. {yields} zT=0.6 at 650 K reproduced for Pb{sub 0.3}Sn{sub 0.1}Ge{sub 0.6}Te. {yields} Pb-rich phases shown to be thermally instable. {yields} Thermoelectric property characterization at low and high temperature. {yields} Microstructural investigations using PXRD, SEM, EDX and PSM.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Synthesis of carbon nanotube/anatase titania composites by a combination of sol-gel and self-assembly at low temperature

A simple method is described for the synthesis of carbon nanotube/anatase titania composites by a combination of a sol-gel method with a self-assembly technique at 65 {sup o}C. This method makes use of polyelectrolyte for wrapping multi-walled carbon nanotube (MWCNT) and providing them with adsorption sites for electrostatically driven TiO{sub 2} nanoparticle deposition. The composites were characterized using X-ray diffraction, transmission electron microscopy, Fourier transform infrared and X-ray photoelectron spectroscopy, and photoluminescence for analyzing their crystal phase, microstructure, particle size, and other physicochemical properties. The results showed that MWCNT were covered with an anatase TiO{sub 2} thin layer or surrounded by an anatase TiO{sub 2} thick coating, which is constructed of TiO{sub 2} particles about 6 nm in size. The composites were rich in surface hydroxyl groups. The excited e{sup -} in conduction band of TiO{sub 2} may migrate to MWCNT. Concerning the potential applicability, MWCNT/TiO{sub 2} composites showed excellent photocatalytic activity toward the photodegradation of methyl orange. -- Graphical abstract: MWCNT/anatase TiO{sub 2} composites have been prepared by a combination of a sol-gel method and a self-assembly technique in one step at low temperature without high temperature calcination. Display Omitted Highlights: {yields} MWCNT/anatase TiO{sub 2} composites could be prepared in one-pot at low temperature. {yields} MWCNT were covered with a TiO{sub 2} thin layer or surrounded by a TiO{sub 2} thick coating. {yields} Composites were rich in surface hydroxyl groups. {yields} Composites showed excellent photodegradation activity of methyl orange.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2010

Immobilization of Thiadiazole Derivatives on Magnetite Mesoporous Silica Shell Nanoparticles in Application to Heavy Metal Removal from Biological Samples

In this report magnetite was synthesized by a coprecipitation method, then coated with a layer of silica. Another layer of mesoporous silica was added by a sol-gel method, then 5-amino-1,3,4-thiadiazole-thiol (ATT) was immobilized onto the synthesized nanoparticles with a simple procedure. This was followed by a series of characterizations, including transmission electron microscopy (TEM), FT-IR spectrum, elemental analysis and XRD. Heavy metal uptake of the modified nanoparticles was examined by atomic absorption spectroscopy. For further investigation we chose Cu{sup 2+} as the preferred heavy metal to evaluate the amount of adsorption, as well as the kinetics and mechanism of adsorption. Finally, the capacity of our nanoparticles for the heavy metal removal from blood was shown. We found that the kinetic rate of Cu{sup 2+} adsorption was 0.05 g/mg/min, and the best binding model was the Freundlich isotherm.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2011

Microstructural features and domain formation in (Ba,Sr){sub 2}TiSi{sub 2}O{sub 8} fresnoites

The formation and co-existence of crystallographically modulated and non-modulated regions in (Ba,Sr){sub 2}TiSi{sub 2}O{sub 8} fresnoites is reviewed, particularly the dependence on local composition. It is shown that perturbations of the average fresnoite structure, determined from appreciable single crystals, are in some cases better described as nanometric domain intergrowths where departures from ideal stoichiometry are characteristics of incommensuration, while modulation is absent from volumes that are less perturbed chemically. Evidence for this differentiation is obtained from selected area electron diffraction (SAED) patterns and high-resolution transmission electron microscopy (HRTEM) images. The domains are readily distinguished by their unique contrast in bright field electron micrographs. Fourier reconstructions of HRTEM images collected from areas with darker contrast show that modulation can change within relatively small volumes. Nearby areas with lighter contrast were found by SAED to be free of structural disorder and incommensurate reflections. - Graphical abstract: Fresnoite layers contain SiO{sub 4} and TiO{sub 5} polyhedra that undergo run rotation and tilting to create 3D, 4D and 5D structural modulations that can be directly observed by electron diffraction and high resolution imaging. Highlights: {yields}(Ba,Sr){sub 2}TiSi{sub 2}O{sub 8} fresnoites contain commensurate and incommensurate domains. > Departures in stoichiometry promote the formation of nanostructured domains. > Domains formation may provide a means for reducing strain in single crystals.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2011

Epitaxial germanidation of full-Heusler Co{sub 2}FeGe alloy thin films formed by rapid thermal annealing

The authors demonstrated that a full-Heusler Co{sub 2}FeGe (CFG) alloy thin film was epitaxially grown by rapid-thermal-annealing-induced germanidation of an Fe/Co/pseudo-Ge(001)-on-insulator (GOI) multilayer formed on a Si-on-insulator (SOI) substrate. X-ray diffraction (XRD) measurements with out-of-plane and in-plane configurations revealed that the CFG film was epitaxially grown along the [001] direction with the in-plane epitaxial relation of CFG[100] parallel GOI[100], although the film slightly contained a non-epitaxial component. The strong (111) and (200) superlattice diffraction intensities indicated that the CFG film had a high degree of order for the L2{sub 1} structure. Cross-sectional high-resolution transmission electron microscopy images of the film revealed that the film had dominant epitaxial and slight non-epitaxial components, which was consistent with the XRD measurements. The epitaxial component was grown directly on the buried oxide layer of the SOI substrate without formation of any interfacial layer.

36 MATERIALS SCIENCE↗