The Origin of Anomalous Strain in Thin Sputtered Mo Films on Si(100)

1991 ◽  
Vol 239 ◽  
Author(s):  
J. Tao ◽  
D. Adams ◽  
S. M. Yalisove ◽  
J. C. Bilello
Keyword(s):  
Film Thickness ◽  
Incidence Angle ◽  
Film Stress ◽  
Structure Evolution ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
Plan View ◽  
X Ray ◽  
Low Incidence ◽  
Diffraction Patterns

ABSTRACTStress and structure evolution in thin films of sputtered Mo on Si(100) substrates has been studied, as a function of microstructure, by x-ray diffraction, transmission electron microscopy (TEM) and Rutherford backscattering spectroscopy (RBS). Double crystal x-ray diffraction topography (DCDT) has been employed to determine film stress as a function of thickness. High compressive stress, about 1000 MPa, is found for the thinnest Mo film. With increasing film thickness a minimal residual stress level is reached. Low incidence angle x-ray diffraction patterns indicated that crystalline Mo is present even in the thinnest films. Line broadening of the Mo(l10) diffraction peak has shown that the grain dimension is comparable to the film thickness over the range studied. Plan view TEM observations of films less than 20nm demonstrated the presence of continuous film with grain dimensions on the order of film thickness, in good agreement with the x-ray results.

An X-Ray Small-Angle Scattering Instrument

1967 ◽  
Vol 11 ◽  
pp. 332-338 ◽  
Author(s):  
Donald M. Koffman
Keyword(s):  
Small Angle ◽  
Scintillation Counter ◽  
Small Angle Scattering ◽  
High Angular Resolution ◽  
X Ray Diffraction ◽  
Multiple Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Angle Scattering ◽  
Diffraction Patterns

AbstractAn X-ray small-angle scattering instrument is described which is used for recording X-ray diffraction patterns or small-angle X-ray scattering curves in an angular region very close to the direct beam. The measurement of X-ray intensity is accomplished with standard geiger or scintillation counter techniques. The instrument is designed for use with a spot-focus or vertical-line X-ray source, In essence, it is a multiple-reflection double-crystal diffractometer, based on a concept developed by Bonse and Hart, employing two grooved perfect germanium crystals arranged in the parallel position. Multiple diffraction from these crystals produces a monochromated X-ray beam which can be several millimeters wide while still exhibiting extremely high angular resolution. As a result, effective sample volumes can be employed with maximum volume-to-thickness ratios. The principal features of the instrument are discussed with emphasis on the advantages of this device over those employing complex slit systems and film-re cording techniques, Data are presented to illustrate the operation, intensity, and resolution of the unit.

Structural properties of molecular beam epitaxy grown Ni/Pt superlattices

1997 ◽  
Vol 12 (1) ◽  
pp. 161-174 ◽  
Author(s):  
W. Staiger ◽  
A. Michel ◽  
V. Pierron-Bohnes ◽  
N. Hermann ◽  
M. C. Cadeville
Keyword(s):  
Molecular Beam ◽  
Growth Direction ◽  
Misfit Dislocations ◽  
X Ray Diffraction ◽  
Plan View ◽  
X Ray ◽  
Transmission Electron ◽  
Superlattice Peak ◽  
Diffraction Peaks ◽  
Diffraction Patterns

We find that the [Ni3.2nmPt1.6nm] × 15 and [Ni3.2nmPt0.8nm] × 15 multilayers are semicoherent and display a columnar morphology. From both the period of the moir’e fringes and the positions of the diffraction peaks in electronic (plan-view and crosssection geometries) and x-ray diffraction patterns, one deduces that the nickel is relaxed (at least in the error bars of all our measurements), whereas the platinum remains slightly strained (≈−1%). The interfaces are sharp; no intermixing takes place giving rise to neat contrasts in transmission electron microscopy (TEM) and to high intensities of the superlattice peaks in the growth direction in both diffraction techniques. The relaxation of the interfacial misfit occurs partially through misfit dislocations, partially through the strain of platinum. A quasiperiodic twinning occurs at the interfaces, the stacking fault which forms the twin being the most often located at the interface Pt/Ni, i.e., when a Pt layer begins to grow on the Ni layer. The simulation of the θ/2θ superlattice peak intensities takes into account the columnar microstructure. It shows that the roughness is predominantly at medium scale with a fluctuation of about 12.5% for Ni layers and negligible for Pt layers.

Film Stress in Pd2Si Layers of Varying Thickness

1985 ◽  
Vol 47 ◽  
Author(s):  
Betty Coulman ◽  
Haydn Chen ◽  
Kenneth Ritz
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Film Stress ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Si Substrates ◽  
Varying Thickness ◽  
Si Films ◽  
Low Coverage

ABSTRACTLittle is known about the development of film stresses in very thin films (thicknesses of the order of a few hundred Angstroms or less). As interest intensifies in the technological application of ever smaller quantities of materials, the behavior of very thin. films will undergo increasing scrutiny. In this study, the film stresses in evaporated Pd films and Pd2Si films formed by reaction with the Si substrates at 250°C were measured for thicknesses ranging from 7 to 107 nm. Stresses were calculated from the substrate radii of curvature determined by X-ray diffraction topography techniques (Lang and double crystal) and Stoney's equation. Because film continuity cannot be taken for granted at low coverage, the films were examined by electron microscopy in an attempt to correlate their morphology with the observed stresses.

High Tc Superconducting Y-Ba-Cu-O Thick Fim by Screen Printing

1987 ◽  
Vol 99 ◽  
Author(s):  
H. H. Yen ◽  
J. H. Kung ◽  
Y. C. Chen ◽  
P. T. Wu
Keyword(s):  
Film Thickness ◽  
Screen Printing ◽  
Copper Oxides ◽  
Onset Temperature ◽  
Superconducting Film ◽  
X Ray Diffraction ◽  
High Tc ◽  
X Ray ◽  
Zero Resistance ◽  
Diffraction Patterns

ABSTRACTSuperconducting film of ternary copper oxides from the Y-Ba-Cu-O system has been prepared by screen printing on 96% A1203 substrate with onset temperature at 95K and zero resistance at 85K. X-ray diffraction patterns show that film will react with the A1203 substrate. With decreasing film thickness the superconductivity is destroyed and may become a semiconductor.

scholarly journals Periodically structured X-ray waveguides

2013 ◽  
Vol 20 (5) ◽  
pp. 691-697 ◽  
Author(s):  
Inna Bukreeva ◽  
Andrea Sorrentino ◽  
Alessia Cedola ◽  
Ennio Giovine ◽  
Ana Diaz ◽  
...  
Keyword(s):  
Periodic Structure ◽  
Incidence Angle ◽  
Far Field ◽  
Phase Synchronism ◽  
Strongly Coupled ◽  
X Ray ◽  
Low Incidence ◽  
Diffraction Patterns ◽  
Theoretical Considerations ◽  
Vacuum Gap

The properties of X-ray vacuum-gap waveguides (WGs) with additional periodic structure on one of the reflecting walls are studied. Theoretical considerations, numerical simulations and experimental results confirm that the periodic structure imposes additional conditions on efficient propagation of the electromagnetic field along the WGs. The transmission is maximum for guided modes that possess sufficient phase synchronism with the periodic structure (here called `super-resonances'). The field inside the WGs is essentially given at low incidence angle by the fundamental mode strongly coupled with the corresponding phased-matched mode. Both the simulated and the experimental diffraction patterns show in the far field that propagation takes place essentially only for low incidence angles, confirming the mode filtering properties of the structured X-ray waveguides.

Texture Analysis of Thin Films and Surface Layers by Low Incidence Angle X-ray Diffraction

1988 ◽  
Vol 32 ◽  
pp. 285-292 ◽  
Author(s):  
J. J. Heizmann ◽  
A. Vadon ◽  
D. Schlatter ◽  
J. Bessières
Keyword(s):  
Thin Films ◽  
Phase Transformation ◽  
Incidence Angle ◽  
X Ray Diffraction ◽  
Electronic Industry ◽  
Surface Layers ◽  
X Ray ◽  
Insufficient Amount ◽  
Reactivity Of Solids ◽  
Low Incidence

It is necessary to know the orientation of thin surface layers for the electronic industry as well as for different studies on interphases (epitaxy, topotaxy, phase transformation, reactivity of solids).It is difficult to obtain information with a conventional Schulz goniometer (Bragg-Brentano geometry) because of the insufficient amount of diffracting material.

Epitaxy Development in thin Superconducting YBa2Cu3O7 Films

1991 ◽  
Vol 237 ◽  
Author(s):  
A. Yen ◽  
L. Li ◽  
J. D. Klein ◽  
W. B. Nowak ◽  
S. F. Cogan
Keyword(s):  
Film Thickness ◽  
High Energy ◽  
Diffraction Reflection ◽  
High Deposition Rate ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Current Densities ◽  
Diffraction Patterns

ABSTRACTUltrathin superconducting YBa2Cu3O7, films were grown on (100) YSZ (yttria-stabilized-zirconia) substrates by off-axis if magnetron sputtering at a relatively high deposition rate. The structure, orientation, and morphology of the films were examined by x-ray diffraction, reflection high-energy electron diffraction (RHEED), and scanning electron microscopy. X-ray diffraction patterns of films deposited on YSZ substrates exhibited strong c-axis alignment with the YBa2Cu3O7 peaks sharpening as the film thickness was increased. The degree of epitaxy apparent in RHEED photographs was found to increase dramatically as the film thickness was increased from 12 nm to 108 nm. This behavior is attributed to a nucleation and growth process in which epitaxy develops as a result of a 3 stage progression from a random to an oriented film.The films were in-situ superconducting, exhibiting superconducting transition temperatures, Tc(0)'s, of 80 K for a 12 nm film and 88 K for a 280 nm film. However, the relatively low critical current densities (Jc < 1 × 106 A/cm2) at 77 K are probably due to a lack of in-plane epitaxy.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

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