The origin of an anomalous, low 2θ peak in x-ray diffraction spectra of MoS2 films grown by ion beam assisted deposition

1997 ◽  
Vol 12 (5) ◽  
pp. 1191-1194 ◽  
Author(s):  
D. N. Dunn ◽  
L. E. Seitzman ◽  
I. L. Singer

The origin of a previously reported anomalous low 2θ x-ray diffraction peak from MoS2 thin films grown by ion beam assisted deposition was investigated. The anomalous peak, observed in a film grown on Si(100), was removed by ion irradiating the film with 180 keV Ar++ ions to a dose of 1 × 1015 ions/cm2. Microstructures of the two films were investigated using x-ray diffraction and cross-section transmission electron microscopy. Diffraction data and bright-field images indicated that the low 2θ peak was due to a local interplanar expansion of the crystal structure normal to MoS2 basal planes. This expansion was attributed to molecular defects.

1998 ◽  
Vol 514 ◽  
Author(s):  
M. F. Wu ◽  
A. Vantomne ◽  
S. Hogg ◽  
H. Pattyn ◽  
G. Langouche ◽  
...  

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.


2010 ◽  
Vol 63 ◽  
pp. 392-395
Author(s):  
Yoshifumi Aoi ◽  
Satoru Furuhata ◽  
Hiromi Nakano

ZrN/TiN multi-layers were synthesized by ion beam sputtering technique. Microstructure and mechanical property of the ZrN/TiN multi-layers were characterized and the relationships between microstructure and hardness of the ZrN/TiN multi-layers with various bilayer thicknesses and thickness ratios were investigated. The microstructure of multi-layers have been investigated using transmission electron microscope (TEM) and X-ray diffraction (XRD).


2000 ◽  
Vol 642 ◽  
Author(s):  
A.L. Gray ◽  
L. R. Dawson ◽  
Y. Lin ◽  
A. Stintz ◽  
Y.-C. Xin ◽  
...  

ABSTRACTAn In(Ga)As-based self-assembled quantum dot laser test structure grown on strain-relief Al0.5Ga0.5As1-ySby strain-relief buffer layers (0≤y ≤ 0.24) on a GaAs substrate is investigated in an effort to increase dot size and therefore extend the emission wavelength over conventional InAs quantum dots on GaAs platforms. Cross-section transmission electron microscopy, and high-resolution x-ray diffraction are used to monitor the dislocation filtering process and morphology in the buffer layers. Results show that the buffer layers act as an efficient dislocation filter by drastically reducing threading dislocations, thus providing a relaxed, low dislocation, compositionally modulated Al0.5Ga0.5Sb0.24As0.76 substrate for large (500Å height x 300Å width) defect -free InAs quantum dots. Photoluminescence shows a ground-state emission of the InAs quantum dots at 1.45 μm.


1994 ◽  
Vol 299 ◽  
Author(s):  
Gary A. Gibson ◽  
Davis A. Lange ◽  
Charles M. Falco

AbstractWe have used Molecular Beam Epitaxy (MBE) to successfully grow films that are predominantly IrSi3 on both Si(111) and Si(100) substrates by codeposition of Si and Ir in a 3:1 ratio. Bragg-Brentano and Seemann-Bohlin x-ray diffraction reveal that polycrystalline IrSi3 films form as low as 450 °C. This is the lowest temperature yet reported for growth of this iridium silicide phase. These x-ray diffraction techniques, along with Transmission Electron Microscope (TEM) diffraction and in situ Low Energy Electron Diffraction (LEED), show that at higher deposition temperatures codeposition can form IrSi3 films on Si(111) that consist predominantly of a single epitaxial growth orientation. Ion beam channeling and x-ray rocking curves show that the epitaxial quality of IrSi3 films deposited on Si(111) is superior to that of IrSi3 films deposited on Si(100). We also present evidence for several new epitaxial IrSi3 growth modes on Si(111) and Si(100).


2014 ◽  
Vol 21 (1) ◽  
pp. 108-119 ◽  
Author(s):  
Daniela Nunes ◽  
Lídia Santos ◽  
Paulo Duarte ◽  
Ana Pimentel ◽  
Joana V. Pinto ◽  
...  

AbstractThe present work reports a simple and easy wet chemistry synthesis of cuprous oxide (Cu2O) nanospheres at room temperature without surfactants and using different precursors. Structural characterization was carried out by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy coupled with focused ion beam and energy-dispersive X-ray spectroscopy. The optical band gaps were determined from diffuse reflectance spectroscopy. The photoluminescence behavior of the as-synthesized nanospheres showed significant differences depending on the precursors used. The Cu2O nanospheres were constituted by aggregates of nanocrystals, in which an on/off emission behavior of each individual nanocrystal was identified during transmission electron microscopy observations. The thermal behavior of the Cu2O nanospheres was investigated with in situ X-ray diffraction and differential scanning calorimetry experiments. Remarkable structural differences were observed for the nanospheres annealed in air, which turned into hollow spherical structures surrounded by outsized nanocrystals.


2006 ◽  
Vol 46 ◽  
pp. 146-151
Author(s):  
Andriy Lotnyk ◽  
Stephan Senz ◽  
Dietrich Hesse

Single phase TiO2 thin films of anatase structure have been prepared by reactive electron beam evaporation. Epitaxial (012)- and (001)-oriented anatase films were successfully obtained on (110)- and (100)-oriented SrTiO3 substrates, respectively. X-ray diffraction and cross section transmission electron microscopy investigations revealed a good epitaxial quality of the anatase films grown on the SrTiO3 substrates.


1993 ◽  
Vol 316 ◽  
Author(s):  
M.F. Wu ◽  
J. De Wachter ◽  
A.-M. Van Bavel ◽  
H. Pattyn ◽  
G. Langouche ◽  
...  

ABSTRACTHeteroepitaxial CoxNi1-xSi2 layers with good crystalline quality have been formed by ion beam synthesis. Rutherford Backscattering (RBS) - Channeling, Auger Electron Spectroscopy (AES), Transmission Electron Microscopy (TEM) and X-Ray Diffraction (XRD) have been used to study the buried layers. For a sample with x=0.66, we found that this ternary suicide layer contains 11% type B and 89 % type A orientation. The TEM investigation reveals that the type B component is mainly located at the interfaces with a thickness of a few monolayers. XRD studies show that the strain of the type B component is smaller than that of the type A component, and this is probably the reason for such a unique distribution of the type B component in the epilayer.


1993 ◽  
Vol 316 ◽  
Author(s):  
W. A. Lewis ◽  
M. Farle ◽  
B. M. Clemens ◽  
R. L. White

ABSTRACTWe report the results of our microstructural investigations into the origin of in-plane uniaxial magnetic anisotropies induced in Ni and Fe thin films by low energy ion beam assisted deposition. 1000 Å films were prepared by ion beam sputtering onto amorphous silica substrates under simultaneous bombardment by 100 eV Xe+ ions under an oblique angle of incidence. The induced anisotropy is studied as a function of ion-to-adsorbate atom arrival ratio, R, from values of 0 to 0.35. The maximum anisotropy field is 150 Oe for Ni and 80 Oe for Fe, but their hard axes are oriented orthogonal to each other. Asymmetric x-ray diffraction is employed to study both in-plane and out-of-plane lattice spacings and crystallographic orientation. In agreement with previous work, we find evidence of a anisotropic in-plane strain of magnitude 0.2-0.5%. In all films, the direction perpendicular to the ion bombardment is compressed relative to parallel. The uniaxial magnetic anisotropy is correlated with this in-plane anisotropic strain using a simple magnetoelastic model.


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