Electron Diffraction Effects in Multi-Layered (Overlapping) Palladium Single-Crystal Films

1971 ◽  
Vol 29 ◽  
pp. 190-191
Author(s):  
G. I. Wong ◽  
H. P. Singh ◽  
L. E. Murr
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Multiple Diffraction ◽  
Polycrystalline Thin Films ◽  
Crystalline Substrate ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Diffraction Patterns ◽  
Diffraction Effects ◽  
Vapor Deposit

Simple multiple diffraction effects dealing with scattered or re-entrant beams in single foils containing twins or crystalline phases giving rise to double diffraction are generally well known. In addition, multiple diffraction arising in two overlapping thin films such as a multiple vapor deposit or an oxide on a crystalline substrate or base film has been studied. There are very few, if any, studies which attempt to systematically describe the diffraction patterns arising from overlapped, rotated, and imperfect single and polycrystalline thin films. This study demonstrates the complicated electron diffraction patterns which can arise by multiple diffraction in laye redarrays of thin Pd films, and describes the origins of some of the observed reflections.

Electron diffraction studies of amorphous and polycrystalline thin films

1990 ◽  
Vol 48 (4) ◽  
pp. 118-119
Author(s):  
D J H Cockayne ◽  
D R McKenzie
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Polycrystalline Materials ◽  
Good Resolution ◽  
Scattered Intensity ◽  
Radial Density ◽  
X Ray ◽  
Polycrystalline Thin Films ◽  
Nitrogen Ion ◽  
Diffraction Patterns

The study of amorphous and polycrystalline materials by obtaining radial density functions G(r) from X-ray or neutron diffraction patterns is a well-developed technique. We have developed a method for carrying out the same technique using electron diffraction in a standard TEM. It has the advantage that studies can be made of thin films, and on regions of specimen too small for X-ray and neutron studies. As well, it can be used to obtain nearest neighbour distances and coordination numbers from the same region of specimen from which HREM, EDS and EELS data is obtained.The reduction of the scattered intensity I(s) (s = 2sinθ/λ ) to the radial density function, G(r), assumes single and elastic scattering. For good resolution in r, data must be collected to high s. Previous work in this field includes pioneering experiments by Grigson and by Graczyk and Moss. In our work, the electron diffraction pattern from an amorphous or polycrystalline thin film is scanned across the entrance aperture to a PEELS fitted to a conventional TEM, using a ramp applied to the post specimen scan coils. The elastically scattered intensity I(s) is obtained by selecting the elastically scattered electrons with the PEELS, and collecting directly into the MCA. Figure 1 shows examples of I(s) collected from two thin ZrN films, one polycrystalline and one amorphous, prepared by evaporation while under nitrogen ion bombardment.

Monocrystalline and Polycrystalline Thin Films Formed by Cobalt Ion Implantation in the Organic Substrate (Polyester)

1994 ◽  
Vol 343 ◽  
Author(s):  
A. L. Stepanov ◽  
R. I. Khaibullin ◽  
S. N. Abdullin ◽  
Yu. N. Osin ◽  
I. B. Khaibullin
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Ion Implantation ◽  
Amorphous State ◽  
Organic Substrate ◽  
Crystalline Lattice ◽  
Cobalt Ion ◽  
Polycrystalline Thin Films ◽  
Transmission Electron ◽  
Diffraction Patterns

ABSTRACTThe structure and phase composition of thin films formed by 40 KeV cobalt ion implantation into organic substrate (polyester) were studied by transmission electron microscopy in conjunction with electron diffraction. Varying current density and dose implantation over the range 0.3×1016 – 2.4×1017 cm-2 we obtained island-like cobalt films of different type as well as labyrinth-like structure at the highest dose value. The granulometric and morphologic parameters were derived from the micrographs of the investigated films. Both amorphous state and α-Co crystalline lattice of cobalt granules were established from electron diffraction patterns of synthesized films. Along with discontinuous films, we formed monocrystalline plates of α-phase cobalt under the determined implantation regimes and conditions. Cross-section images of synthesized films showed that films are of about 300 Å thick and buried at the depth of 150 Å from the principal surface of the polyester.

Precipitation in Al + 4% Cu Epitaxial Films

1968 ◽  
Vol 26 ◽  
pp. 384-385
Author(s):  
S. Herd ◽  
S. M. Mader
Keyword(s):  
Solid Solution ◽  
Bulk Material ◽  
Epitaxial Films ◽  
Detectable Change ◽  
Cu Films ◽  
Solution Treated ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Diffraction Patterns ◽  
Deposited Films

Single crystal films in (001) orientation, about 1500 Å thick, were produced by R-F sputtering of Al + 4 wt % Cu onto cleaved KCl at 150°C substrate temperature. The as-deposited films contained numerous θ-CuAl2 particles (C16 structure) about 0.1μ in size. They were transferred onto Mo screens, solution treated and rapidly cooled (within about ½ min) so as to retain a homogeneous solid solution. Subsequently, the films were aged in vacuum at various temperatures in order to induce precipitation and to compare structures and morphologies of precipitate particles in Al-Cu films with those found in age hardened bulk material.Aging for 3 weeks at 60°C or 48 hrs at 100°C did not produce any detectable change in high resolution micrographs or diffraction patterns. In this range Guinier-Preston zones (GP) form in quenched bulk material. The absence of GP in the present experiments in this aging range is perhaps due to the cooling rate employed, which might be more equivalent to an aged and reverted bulk material than to a quenched one.

Electron diffraction detection of ordliking in annealed PbTe thin film

1990 ◽  
Vol 48 (4) ◽  
pp. 1018-1019
Author(s):  
Karimat El-Sayed
Keyword(s):  
Thin Film ◽  
Electron Diffraction ◽  
Lead Telluride ◽  
Structural Basis ◽  
Face Centered Cubic ◽  
X Ray ◽  
Polycrystalline Thin Films ◽  
Stage Process ◽  
Diffraction Patterns ◽  
Face Centered

Lead telluride is an important semiconductor of many applications. Many Investigators showed that there are anamolous descripancies in most of the electrophysical properties of PbTe polycrystalline thin films on annealing. X-Ray and electron diffraction studies are being undertaken in the present work in order to explain the cause of this anamolous behaviour.Figures 1-3 show the electron diffraction of the unheated, heated in air at 100°C and heated in air at 250°C respectively of a 300°A polycrystalline PbTe thin film. It can be seen that Fig. 1 is a typical [100] projection of a face centered cubic with unmixed (hkl) indices. Fig. 2 shows the appearance of faint superlattice reflections having mixed (hkl) indices. Fig. 3 shows the disappearance of thf superlattice reflections and the appearance of polycrystalline PbO phase superimposed on the [l00] PbTe diffraction patterns. The mechanism of this three stage process can be explained on structural basis as follows :

Computer Analysis of Electron Diffraction From thin Films

1998 ◽  
Vol 4 (S2) ◽  
pp. 344-345
Author(s):  
Warren MoberlyChan ◽  
R. Kilaas ◽  
L-H. Chan ◽  
T. Nolan ◽  
P. Dorsey ◽  
...  
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Computer Processing ◽  
Information Storage ◽  
Engineering Properties ◽  
Digital Recording ◽  
Longitudinal Recording ◽  
Diffraction Patterns ◽  
User Friendly ◽  
Co Alloys

As engineering properties are miniaturized by mo thinner films, crystallographic analyses become more appropriate by electron diffraction than XRD. Without synchrotron sources, XRD scans of such films often expose one peak at best. However, these thinner films become more suited for TEM, with less artifacts from sample preparation. XRD scans with peaks in the noise are quantitatively accepted, while vast differences in electron diffraction patterns remain unquantified. Digital recording of TEM information removes the uncertain hand waving of the darkroom; and fast, user-friendly computer processing especially removes the nonstatistical art in image analysis. This work inputs 16-bit (>65,000 gray levels) images of ring diffraction patterns into Digital Micrograph and utilizes a Rotation Average subroutine (1) to plot peak intensities.Information storage in a hard drive utilizes sputtered thin films of HCP-Co-alloys with magnetic bits tied to the crystallographic orientation of each grain. Longitudinal-recording density and signal-to-noise can be enhanced for thin films with c-axes of all grains in plane.

UMWEG-98: a program for calculation and graphical representation of multiple diffraction patterns

1999 ◽  
Vol 32 (2) ◽  
pp. 355-361 ◽  
Author(s):  
Elisabeth Rossmanith
Keyword(s):  
Graphical Representation ◽  
Software Tool ◽  
Crystal Structure Analysis ◽  
Diffraction Peak ◽  
Current Version ◽  
Multiple Diffraction ◽  
Peak Location ◽  
Diffraction Patterns ◽  
Diffraction Effects ◽  
A Current

UMWEG-XX was designed as a software tool for taking into account multiple diffraction effects in many areas of crystal structure analysis. TheUMWEG-98 version of the program makes possible the calculation and graphical representation of multiple diffraction patterns (Renninger scans, multiple diffraction peak location plots) of forbidden and weak reflections and can be applied to synchrotron as well asKα1,2radiation. The program is written in standard Fortran90 and may be ported to Unix platforms, such as HP, Sun, Silicon Graphics and IBM, as well as to DOS and Windows platforms. The program runs without any commercial subroutine libraries. Consequently it can be used without licence problems. A current version is distributedviahttp://www.rrz.uni-hamburg.de/mpi/rossmanith. Executable (binary) files are available free of charge for academic use only.

Electron Diffraction Investigation of Crystallographic Texture of Thin Films

1999 ◽  
Vol 562 ◽  
Author(s):  
Li Tang ◽  
Shanlin Duan ◽  
David E. Laughlin
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Crystallographic Texture ◽  
Film Plane ◽  
Electron Diffraction Investigation ◽  
Texture Axis ◽  
Circular Arcs ◽  
Ewald Sphere ◽  
Diffraction Patterns ◽  
Multilayered Thin Films

ABSTRACTA method of investigating thin film crystallographic texture by electron diffraction is reviewed. The reciprocal lattices of fibrous and lamellar textured thin films are spherical belts around the texture axis. Equations describing the projection of the spherical belts onto the Ewald sphere along the texture axis direction are presented. Based on these equations the geometric and intensity evolution of the electron diffraction patterns with the tilt angle about an arbitrary axis in the film plane can be analyzed in a systematic way. The geometric characteristics of the electron diffraction patterns are then used to derive the texture axis directional index and its angular distribution. The way to determine the equal-intensity circular arcs on the diffraction pattern is also discussed. This method can be applied to both single layered and multilayered thin films of various applications.

Epitaxial growth of Cu-Ni Single Crystal Alloys and Multilayers by Molecular Beam Epitaxy

1989 ◽  
Vol 160 ◽  
Author(s):  
R.P. Burns ◽  
Y.H. Lee ◽  
N.R. Parikh ◽  
J.B. Posthill ◽  
M.J. Mantini ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Beam Epitaxy ◽  
Single Crystal ◽  
Epitaxial Growth ◽  
Molecular Beam ◽  
Substrate Material ◽  
High Reactivity ◽  
Lattice Match ◽  
Single Crystal Films ◽  
Crystal Films

AbstractEpitaxial growth of thin films, alloys, and multilayers from the Cu-Ni system are being explored as a means of fabricating a substrate to lattice match diamond. These single crystal films are superior to commercially available substrate material. Due to the high reactivity of the metal surfaces in atmosphere, all processing must be done under UHV conditions. In vacuo preparation, growth, and analysis of the metals is described.

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