Structure of an asymmetrical tilt boundary in gold

1988 ◽  
Vol 46 ◽  
pp. 604-605
Author(s):  
Hans Norden ◽  
David A. Smith
Keyword(s):  
Grain Boundaries ◽  
Periodic Boundary ◽  
Direct Evidence ◽  
Tilt Boundary ◽  
Physical Significance ◽  
Dislocation Model ◽  
Short Period ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Oriented Single Crystal

Balluffi and coworkers developed a technique for making grain boundaries, with chosen misorientations, by welding together appropriately oriented single crystal films. This technique has been used to make gold bicrystals with a misorientation which does not correspond to any short period structure of the kind which is usually thought to have low energy. The procedure followed was to join {100} and {111} single films with <110> directions in each film approximately parallel. With [110](001) and [110](111) exactly parallel an asymmetrical tilt boundary with misorientation 54.73°/[110] is produced. For Σ, the reciprocal fraction of coincidence sites <50, the periodic boundary structures nearest in misorientation are 50.48°/[l10], Σ=11; 55.88°/[110], Σ = 33. Analysis of the present boundaries can therefore give direct evidence relating to the controversial question of the extent of the physical significance of the dislocation model for grain boundaries.Fig. 1 shows a typical region of the interface. Patches of grain boundary are surrounded by regions where the two films are not in contact.

A new method for preparing tilt grain boundaries in thin vapor-deposited films

1987 ◽  
Vol 45 ◽  
pp. 280-281
Author(s):  
William Krakow ◽  
Victor Castaño
Keyword(s):  
Grain Boundaries ◽  
Boundary Migration ◽  
Ion Milling ◽  
The Past ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Tilt Boundaries ◽  
Deposited Films ◽  
Twist Boundaries

In the past the electron microscope samples used to study tilt grain boundaries and interfaces were prepared from bulk samples grown from the melt which were then cut, polished and thinned by ion milling or chemical jet etching. This technique is also employed routinely in preparing crossectional semiconductor materials and metals. Another technique to prepare tilt boundaries in metals is to fuse two thin single crystal films each on substrates by heating and forming twist boundaries (e.g. Au (100)). Then, the boundary which forms at the composite film midplane, migrates to one of the two films surfaces having many island grains separated by tilt boundaries perpendicular to the foils’ surface. One of the present authors has carried this technique further by being able to perform this process directly in the microscope and observe the boundary migration when the total film thickness, in the case of Au, was ∼250Å. The technique is limited to this composite thickness because small holes develop in thinner films which thin rapidly become discontinuous when heated in-situ.

Beam Shaping for Cw Laser Recrystallization of Polysilicon Films

1982 ◽  
Vol 13 ◽  
Author(s):  
P. Zorabedian ◽  
C.I. Drowley ◽  
T.I. Kamins ◽  
T.R. Cass
Keyword(s):  
Single Crystal ◽  
Grain Boundaries ◽  
Beam Shaping ◽  
Grain Structure ◽  
Shaped Beam ◽  
Cw Laser ◽  
Laser Recrystallization ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Polysilicon Films

ABSTRACTA shaped laser beam has been used for laterally seeded recrystallization of polysilicon films over oxide. Direct maps of the shaped-beam intensity distribution in the wafer plane are correlated with the grain structure of the recrystallized polysilicon. Using 60% overlapping of shaped-beam scans along <100> directions, we have obtained seeded areas one mm wide and 50 to 500μm long. These consist of 40μm-wide adjacent single-crystal strips regularly separated by low-angle grain boundaries extending laterally away from the seed openings. The spacing between grain boundaries is equal to the scan spacing, providing a means for controlling the location of grain boundaries in otherwise defect-free, single-crystal films.

Mechanical Properties and Microstructure of Cu/Cu-Ni And Cu/Ag Multilayer thin Films

1994 ◽  
Vol 356 ◽  
Author(s):  
James E. Krzanowski ◽  
Peter Duggan
Keyword(s):  
Mechanical Properties ◽  
Modulation Amplitude ◽  
Interface Width ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Magnetron Sputter Deposition ◽  
Computer Controlled ◽  
Magnetron Sputter ◽  
Controlled Deposition ◽  
Oriented Single Crystal

AbstractThe mechanical properties of thin-film Cu/Cu-Ni and Cu/Ag multilayers are examined in this study. Films were prepared by magnetron sputter deposition onto cleaved NaCl substrates. The use of a computer-controlled deposition system enabled the multilayer interface width to be varied, as well as the multilayer amplitude and bilayer thickness. The Cu/Cu-Ni multilayers had the form of (001) oriented single crystal films, but for Cu-Ag multilayers only polycrystalline films could be obtained in the (001) orientation. For Cu/Cu-15%Ni multilayers, the tensile strengths were measured and observed to increase with decreasing interface width at constant wavelength. Tensile strengths were also found to increase with increasing composition modulation amplitude. For films with constant interface width but bilayer thicknesses ranging from 10 to 60 nm, the tensile strength was relatively constant. The results are consistent with previous theoretical treatments, particularly the theory of modulus hardening.

Preparation and crystal properties of thin InSb films for highly sensitive magnetoresistance elements

1986 ◽  
Vol 1 (4) ◽  
pp. 547-551 ◽  
Author(s):  
Masaaki Isai ◽  
Toshiaki Fukunaka ◽  
Masahide Ohshita
Keyword(s):  
Electron Mobility ◽  
Low Cost ◽  
High Sensitivity ◽  
High Electron ◽  
Transmission Electron ◽  
Highly Sensitive ◽  
Crystal Properties ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Oriented Single Crystal

High electron mobility thin InSb films were prepared on mica substrates by conventional vacuum evaporation of InSb to obtain highly sensitive magnetoresistance (MR) elements. The 0.15–0.5 μm thick InSb films were prepared in the present work. An optimum evaporation programming pattern was obtained. The crystal properties of these InSb films of 0.2–0.3 μm were investigated using a transmission electron microscope. It was shown that films thinner than 0.2 μm were semitransparent and consisted of [111] oriented single-crystal films. The 0.15–0.3 μm thick InSb films are therefore most useful for low-cost MR elements because of their high element resistance, small temperature coefficient of electron mobility, and high sensitivity.

Structure of Palladium Single-Crystal Films Prepared by Flash Evaporation onto (001) NaCl Substrates

1970 ◽  
Vol 28 ◽  
pp. 456-457
Author(s):  
L. E. Murr ◽  
G. Wong
Keyword(s):  
Single Crystal ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
High Rate ◽  
Flash Evaporation ◽  
Optimum Load ◽  
Single Crystal Films ◽  
Crystal Films ◽  
A Current

Palladium single-crystal films have been prepared by Matthews in ultra-high vacuum by evaporation onto (001) NaCl substrates cleaved in-situ, and maintained at ∼ 350° C. Murr has also produced large-grained and single-crystal Pd films by high-rate evaporation onto (001) NaCl air-cleaved substrates at 350°C. In the present work, very large (∼ 3cm2), continuous single-crystal films of Pd have been prepared by flash evaporation onto air-cleaved (001) NaCl substrates at temperatures at or below 250°C. Evaporation rates estimated to be ≧ 2000 Å/sec, were obtained by effectively short-circuiting 1 mil tungsten evaporation boats in a self-regulating system which maintained an optimum load current of approximately 90 amperes; corresponding to a current density through the boat of ∼ 4 × 104 amperes/cm2.

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.

Bright-Field Images (Ctem) of Phase Objects at High Resolution

1976 ◽  
Vol 34 ◽  
pp. 490-491 ◽  
Author(s):  
Sumio Iijima
Keyword(s):  
High Resolution ◽  
Electron Beam Irradiation ◽  
Fine Particles ◽  
High Resolution Electron Microscopy ◽  
Good Test ◽  
Resolution Electron ◽  
Single Crystal Films ◽  
Crystal Films ◽  
By Products ◽  
Test Objects

We have developed a technique to prepare thin single crystal films of graphite for use as supporting films for high resolution electron microscopy. As we showed elsewhere (1), these films are completely noiseless and therefore can be used in the observation of phase objects by CTEM, such as single atoms or molecules as a means for overcoming the difficulties because of the background noise which appears with amorphous carbon supporting films, even though they are prepared so as to be less than 20Å thick. Since the graphite films are thinned by reaction with WO3 crystals under electron beam irradiation in the microscope, some small crystallites of WC or WC2 are inevitably left on the films as by-products. These particles are usually found to be over 10-20Å diameter but very fine particles are also formed on the film and these can serve as good test objects for studying the image formation of phase objects.

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