Stress in Sputtered Co90Fe10/Ag GMR Multilayers

1996 ◽  
Vol 436 ◽  
Author(s):  
J. D. Jarratt ◽  
V. R. Inturi ◽  
J. L. Weston ◽  
J. A. Barnard
Keyword(s):  
Giant Magnetoresistance ◽  
Room Temperature ◽  
Multilayer Films ◽  
Antiferromagnetic Coupling ◽  
High Temperature Annealing ◽  
X Ray Diffraction ◽  
Hexagonal Symmetry ◽  
Individual Layer ◽  
X Ray ◽  
The Difference

AbstractStress, giant magnetoresistance (GMR), structure, and magnetic properties of sputtered (Co90Fe10X Å/Ag Y Å)×20 multilayer films have been investigated at room temperature where X ranges from 7.5 to 25 Å and Y from 10 to 60 Å. These films exhibit distinct GMR behaviors dependent on individual layer thicknesses, including layered granular-type GMR in CoFe 7.5 Å samples and ‘discontinuous’ GMR (DGMR) in CoFe 15 and 25 Å samples with Ag thicknesses over 30 Å. No antiferromagnetic coupling was observed. CoFe 10 Å samples act as a transition between GMR behaviors. Compressive stress decreases with increasing Ag thickness in the CoFe 7.5 Å samples. In the CoFe 15 and 25 Å samples the stress fluctuates similarly depending on Ag thickness. The difference in stress and MR behavior between the CoFe 7.5 Å and the 15 and 25 Å samples is thought to be due to incomplete CoFe layering in the CoFe 7.5 Å samples. In the CoFe 15 Å DGMR samples, high temperature annealing resulted in tensile stresses large enough to cause film detachment. X-ray diffraction reveals a strong (111) growth texture as well as satellite peaks from coherent layering. This (111) texture is also evidenced by patterns with hexagonal symmetry formed by the detached films.

GMR and Structure in Sputtered Co90Fe10/Ag Multilayers

1995 ◽  
Vol 403 ◽  
Author(s):  
J. D. Jarratt ◽  
J. A. Barnard
Keyword(s):  
Magnetic Properties ◽  
Multilayer Structure ◽  
Giant Magnetoresistance ◽  
Multilayer Films ◽  
X Ray Diffraction ◽  
Individual Layer ◽  
X Ray ◽  
The Individual

AbstractGiant magnetoresistance (GMR), structure, and magnetic properties of sputtered (Co90Fe10 X Å/Ag Y Å) multilayer films have been investigated. Distinct GMR behaviors including granulartype (GGMR) and ‘discontinuous’ (DGMR) are observed which are strongly dependent on the individual CoFe and Ag layer thicknesses; however, standard multilayer GMR and the associated antiferromagnetic (AFM) coupling is absent. The multilayer structure, individual layer thicknesses, and growth texture were investigated using high and low angle x-ray diffraction (HXRD & LXRD).

Study of thermal properties of Ga0.5In1.5Se3 by differential scanning calorimetry

2021 ◽  
pp. 2150407
Author(s):  
S. I. Ibrahimova
Keyword(s):  
Crystal Structure ◽  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Thermal Effects ◽  
Room Temperature ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
Hexagonal Symmetry ◽  
Scanning Calorimetry ◽  
X Ray

The crystal structure and thermal properties of the [Formula: see text] compound have been investigated. Structural studies were performed by X-ray diffraction at room temperature. The crystal structure of this compound was found to correspond to the hexagonal symmetry of the space group P61. Thermal properties were studied using a differential scanning calorimetry (DSC). It was found in the temperature range [Formula: see text] that thermal effects occur at temperatures [Formula: see text] and [Formula: see text]. The thermodynamic parameters of these effects are calculated.

Self-Assembly of Inorganic/Organic Multilayer Films

1994 ◽  
Vol 351 ◽  
Author(s):  
Astrid C. Zeppenfeld ◽  
Catherine J. Page
Keyword(s):  
Self Assembly ◽  
Grazing Angle ◽  
Multilayer Films ◽  
Silicon Wafers ◽  
Initial Surface ◽  
X Ray Diffraction ◽  
Individual Layer ◽  
X Ray ◽  
Influence Of Substrate ◽  
The Individual

ABSTRACTIn order to investigate the influence of substrate functionalization on the subsequent selfassembly of multilayer films, multilayers composed of alternating hafnium and 1,10-decanediylbis(phosphonic) acid (DBPA) have been grown on three different substrates. Substrates studied include gold wafers functionalized with 4-mercaptobutylphosphonic acid, silicon wafers functionalized using a hafnium oxychloride solution, and silicon wafers coated with an octadecylphosphonate LB-template layer. The nature of these films is probed using ellipsometry and grazing angle x-ray diffraction. These studies indicate that the overall order and the individual layer thickness can vary substantially from sample to sample and depend strongly on the initial surface functionalization prior to multilayer growth.

Giant Magnetoresistance in Annealed Fe/Cr Multilayers

1993 ◽  
Vol 313 ◽  
Author(s):  
Noa More Rensing ◽  
Bruce M. Clemens
Keyword(s):  
Giant Magnetoresistance ◽  
Structural Effect ◽  
Magnetic Effect ◽  
Antiferromagnetic Coupling ◽  
X Ray Diffraction ◽  
Magnetoresistance Effect ◽  
X Ray ◽  
Giant Magnetoresistance Effect ◽  
Higher Temperature ◽  
Spin Dependent Scattering

ABSTRACTThe giant magnetoresistance effect in antiferromagnetically coupled Fe/Cr Multilayers has been attributed to spin dependent scattering at the interfaces between the constituents. One possible source of this spin dependent scattering is chromium impurities in the iron layers due to intermixing at the interfaces. Annealing the films can promote the diffusion of the components, increasing the impurity concentration and therefore the Magnetoresistance. For this study Fe/Cr Multilayers were annealed at several temperatures and for several durations. Annealing at moderate temperatures (∼ 350°C) increases the Magnetoresistance, while higher temperature anneals (∼ 600°C) cause the magnetoresistance to disappear completely. Long anneals at 330°C (> 100 hours) also reduce the Magnetoresistance. VSM Measurements indicate that the antiferromagnetic coupling is reduced in the annealed samples but show no evidence of Magnetically “dead” alloy layers. Low angle X-ray diffraction indicates that the structural effect of annealing is very subtle in comparison to the significant magnetic effect.

Crystal and Molecular Structure of Di-μ-phenoxido-bis-[N-{(2-hydroxybenzyl)-(S)-alaninato-κ3-O,O',N}copper(II)]. A Simple Homodimetallic Model for N-terminal Tyrosine Coordination with (S)-Alanine as a Second Amino Acid Residue

1998 ◽  
Vol 63 (3) ◽  
pp. 356-362 ◽  
Author(s):  
Svetlana Pakhomova ◽  
Jan Ondráček ◽  
František Jursík
Keyword(s):  
Molecular Structure ◽  
Room Temperature ◽  
Crystal And Molecular Structure ◽  
Carbonyl Oxygen ◽  
Antiferromagnetic Coupling ◽  
X Ray Diffraction ◽  
Apical Position ◽  
X Ray ◽  
Pyramidal Geometry ◽  
Square Pyramidal Geometry

Single-crystal X-ray diffraction study established the dimeric [Cu2(ohb-(S)-Ala)2] structure (ohb-(S)-Ala = N-(2-hydroxybenzyl-(S)-alaninate). The complex crystallizes in the tetragonal space group P43212 with a = b = 8.849(1) Å, c = 24.913(2) Å, V = 1950.8(3) Å3, Z = 8. The Cu(II) ion has distorted square-pyramidal geometry with the equatorial positions occupied by three oxygen and one nitrogen atom. Each copper atom is weakly coordinated at the apical position by carbonyl oxygen atom of the neighbouring molecule at the distance 2.329(2) Å. The Cu-Cu separation 3.0204(7) Å and the Cu-O3-Cu angle 100.8(1)° lead to antiferromagnetic coupling (at room temperature μeff = 1.35 μB). The O1-Cu-O3 angle (154.9(1)°) indicates distortion of the square pyramid toward a trigonal bipyramid (t = 0.23).

Enhanced Hardness and Stress-Driven Delamination in Fe/Pt Multilayers

1995 ◽  
Vol 382 ◽  
Author(s):  
B.J. Daniels ◽  
W.D. Nix ◽  
B.M. Clemens
Keyword(s):  
Room Temperature ◽  
Multilayer Films ◽  
Film Structure ◽  
Film Stress ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bilayer Period ◽  
Sputter Deposited ◽  
Epitaxial Multilayers ◽  
Qualitative Discussion

ABSTRACTPolycrystalline Fe/Pt multilayers of varying bilayer period, Λ, were sputter deposited onto SiO2 at room temperature. Film structure was characterized by x-ray diffraction, hardness was determined using nanoindentation, and stresses were examined with wafer curvature. The Fe layers were shown to be predominantly {110} oriented while the Pt layers were mostly {111} oriented. The hardnesses of these multilayer films were enhanced over the rule of mixtures value by a factor of almost 3 and exhibited a dependence on Λ which was similar to that previously observed in epitaxial Fe(001)/Pt(001) multilayers. The hardnesses of the polycrystalline multilayers were higher than those of the epitaxial multilayers, presumably due to grain boundary strengthening in these films. Film stress was large (∼1.5 GPa) and compressive, resulting in buckling-driven delamination of the film from the substrate for films with 40≤Λ≤100 Å. Delamination occurred in the “telephone cord” morphology and was observed in real time. A qualitative discussion of our observations of this delamination mechanism is presented.

Two- and Three-Beam X-ray Diffraction Imaging of Domains in Magnetite

1998 ◽  
Vol 31 (5) ◽  
pp. 726-732
Author(s):  
C. Medrano ◽  
F. Heyroth ◽  
M. Schlenker ◽  
J. Baruchel ◽  
J. Espeso
Keyword(s):  
Synchrotron Radiation ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Large Crystal ◽  
Angular Sensitivity ◽  
X Ray ◽  
Diffraction Imaging ◽  
The Difference ◽  
Topographic Imaging ◽  
Radiation Beams

The X-ray diffraction topographic imaging process for ferrimagnetic domains in magnetite Fe3O4at room temperature is investigated, in two- and three-beam cases, for incident synchrotron radiation beams differing in angular divergence and energy spread. In the usual two-beam configuration, domain or wall contrast is obtained from the difference in Bragg conditions, or from the slight difference in the direction of the beams diffracted by neighbouring domains, revealed by the large crystal-to-film distance that can be used at a third-generation synchrotron radiation facility. A three-beamUmweganregungcase involving the weak 171 and the strong 131 reflections shows unusual domain contrast on the 171 topographs, even on images involving energy or angle integration; this contrast is particularly evident on white-beam topographs. The high angular sensitivity this implies is associated with the difference in dispersion relation between the two reflections.

A three-dimensional cyanide-bridged heterometallic coordination polymer: poly[[diacetonitrilediaqua[μ2-3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine-κ4N1,N6:N3,N4]tetra-μ-cyanido-tetracyanidodimanganese(II)molybdate(IV)] dihydrate]

2014 ◽  
Vol 70 (11) ◽  
pp. 1029-1032 ◽  
Author(s):  
Xiao-Juan Xu
Keyword(s):  
Magnetic Properties ◽  
Ir Spectroscopy ◽  
Coordination Polymer ◽  
Elemental Analysis ◽  
Room Temperature ◽  
Three Dimensional ◽  
Antiferromagnetic Coupling ◽  
X Ray Diffraction ◽  
X Ray ◽  
Magnetic Investigation

A metal coordination polymer, {[Mn2Mo(CN)8(C12H8N6)(CH3CN)2(H2O)2]·2H2O}n, has been synthesized by the reaction of Mn(ClO4)2·6H2O with 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine (bptz) and (Bu3N)3[Mo(CN)8] at room temperature. The polymer was characterized by IR spectroscopy, elemental analysis and X-ray diffraction, and the magnetic properties were also investigated. The X-ray diffraction analysis reveals that the compound is a new three-dimensional coordination polymer with a PtS-type network. Magnetic investigation shows antiferromagnetic coupling between adjacent Mn2+cations.

Preparation and Structure of Cu-W Multilayers

1988 ◽  
Vol 132 ◽  
Author(s):  
K. M. Unruh ◽  
B. M. Patterson ◽  
S. I. Shah ◽  
G. A. Jones ◽  
Y.-W. Kim ◽  
...  
Keyword(s):  
Room Temperature ◽  
Melting Behavior ◽  
High Angle ◽  
X Ray Diffraction ◽  
Individual Layer ◽  
X Ray ◽  
Transmission Electron ◽  
Angle Scattering ◽  
Interesting Candidate ◽  
Xrd And Tem

ABSTRACTSputtered multilayer samples of W and Cu have been prepared on a variety of substrates with nominal individual layer thicknesses ranging from about 5 to about 100 A. High angle X-Ray Diffraction (XRD) data have been obtained at room temperature on all of these samples. In addition, selected samples have been studied by Transmission Electron Microscopy (TEM) and by low and high angle XRD from room temperature to above the melting point of bulk Cu. XRD and TEM data indicate that the as-deposited multilayer samples are comprised of well-defined individual layers due, in part, to the very small mutual solubility of W and Cu. At high temperatures the existence of low angle scattering peaks as well as satellites about Bragg peaks indicates that the layered structure is not lost. As a result, the W-Cu multilayer system seems to be an interesting candidate for the study of the melting behavior of thin Cu layers.

Crystal Structure of the Adduct Hexahydroxotelluric Acid-Disodium Ethylenediaminetetraacetate-Water (1/1/2)

1995 ◽  
Vol 60 (5) ◽  
pp. 820-828 ◽  
Author(s):  
Ivana Císařová ◽  
Jana Podlahová ◽  
Jaroslav Podlaha
Keyword(s):  
Crystal Structure ◽  
Room Temperature ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Hexagonal Symmetry ◽  
X Ray ◽  
Molar Ratios ◽  
Sodium Cations ◽  
High Diffraction ◽  
Disodium Ethylenediaminetetraacetate

The title compound crystallizes in the form of racemic twins of hexagonal symmetry from slightly acidic aqueous solutions containing H6TeO6 and Na2H2edta in a broad range of molar ratios. The crystals are of excellent quality and high diffraction power, thus enabling the structure determination with a precission not routinely attainable by conventional single crystal X-ray diffraction (R = 0.015 at room temperature). The building units of the structure, held together by a system of hydrogen bonds, are the octahedral Te(OH)6 molecule, the H2edta2- anion with protonated nitrogens, two water molecules and two sodium cations surrounded by ten oxygens in the O4Na(mi-O)2NaO4 moiety of irregular geometry.

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