Movement of the spinel-wustite interface in thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105898 ◽

1988 ◽

Vol 46 ◽

pp. 766-767

Author(s):

Scott R. Summerfelt ◽

C.B. Carter

Keyword(s):

Thin Films ◽

Interfacial Energy ◽

Strain Energy ◽

Lattice Misfit ◽

Particle Morphology ◽

Interface Boundary ◽

Flat Plates ◽

Oxygen Sublattice

The wustite-spinel interface boundary can be thought of as a model interface since wustite and spinel share a common f.c.c. oxygen sublattice with only the cations changing across the interface. However, a wide variety of spinel precipitate morphologies has been experimentally observed and ranges from flat plates parallel to {001} planes in the MgAl2O4-MgO system, to coherent ellipsoids parallel to the {001} planes in the NiCr2O4-NiO system, to large coherent particles having “arms” in the <001> direction bounded by {111~ and {110~ planes in the NiFe2O4-NiO system. The particle morphology is determined by a combination of the interfacial energy and the strain energy which results from the lattice misfit between the wustite matrix and the spinel precipitate. In this study, a TEM sample was made containing spinel particles precipitated in the bulk. Individual precipitates were then characterized between a series of anneals.

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The wustite-spinel interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126226 ◽

1987 ◽

Vol 45 ◽

pp. 268-269

Author(s):

S.R. Summerfelt ◽

C.B. Carter

Keyword(s):

Solid State ◽

Solid State Reaction ◽

Strain Energy ◽

Matrix Material ◽

Lattice Misfit ◽

Solid State Reactions ◽

Oxygen Sublattice ◽

Large Particles ◽

Small Lattice ◽

Coherent Interfaces

The wustite-spinel interface can be viewed as a model interface because the wustite and spinel can share a common f.c.c. oxygen sublattice such that only the cations distribution changes on crossing the interface. In this study, the interface has been formed by a solid state reaction involving either external or internal oxidation. In systems with very small lattice misfit, very large particles (>lμm) with coherent interfaces have been observed. Previously, the wustite-spinel interface had been observed to facet on {111} planes for MgFe2C4 and along {100} planes for MgAl2C4 and MgCr2O4, the spinel then grows preferentially in the <001> direction. Reasons for these experimental observations have been discussed by Henriksen and Kingery by considering the strain energy. The point-defect chemistry of such solid state reactions has been examined by Schmalzried. Although MgO has been the principal matrix material examined, others such as NiO have also been studied.

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Interface and Strain Energy Revolution Texture Map To Predict Structure and Optical Properties of Sputtered PbSe Thin Films

ACS Applied Materials & Interfaces ◽

10.1021/acsami.5b09724 ◽

2015 ◽

Vol 8 (1) ◽

pp. 625-633 ◽

Cited By ~ 22

Author(s):

Xigui Sun ◽

Kewei Gao ◽

Xiaolu Pang ◽

Huisheng Yang

Keyword(s):

Thin Films ◽

Optical Properties ◽

Strain Energy

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Thermodynamic modeling of elastic mismatch strain energy on epitaxial growth of GaInN thin films

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2019.05.225 ◽

2019 ◽

Vol 798 ◽

pp. 112-118

Author(s):

Xinyuan Hu ◽

Lei L. Kerr ◽

Xushan Zhao ◽

Chen Ling ◽

Zhengjing Zhao ◽

...

Keyword(s):

Thin Films ◽

Epitaxial Growth ◽

Thermodynamic Modeling ◽

Strain Energy ◽

Mismatch Strain ◽

Elastic Mismatch

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Effects of interfacial energy and annealing on the microstructure of NiTe2 thin films on glass substrate

International Journal of Nanotechnology ◽

10.1504/ijnt.2018.096351 ◽

2018 ◽

Vol 15 (6/7) ◽

pp. 611

Author(s):

Lee Sung Hyuk ◽

Tae Won Yuk ◽

Kyu Hyoung Lee ◽

Suk Jun Kim

Keyword(s):

Thin Films ◽

Interfacial Energy ◽

Glass Substrate

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Void and Dislocation Microstructure Development in Heteroepitaxial Film Growth

MRS Proceedings ◽

10.1557/proc-399-371 ◽

1995 ◽

Vol 399 ◽

Author(s):

Richard W. Smith ◽

David J. Srolovitz

Keyword(s):

Thin Films ◽

Molecular Dynamics ◽

Film Growth ◽

Lattice Misfit ◽

Two Dimensional ◽

Microstructure Development ◽

Non Equilibrium Molecular Dynamics ◽

Dynamics Simulations ◽

Film Substrate ◽

Edge Dislocations

ABSTRACTTwo dimensional, non-equilibrium molecular dynamics simulations have been performed to examine the microstructures of both homoepitaxial and heteroepitaxial thin films grown on single crystal substrates. The principal microstructural features to develop within these films are small voids and edge dislocations. Voids form near the surface of the growing film as surface depressions between microcolumns pinch off to become closed volumes. These voids often form in such a way as to introduce dislocations into the crystal with their cores positioned within the voids. Dislocations are also formed during heteroepitaxy at the interface between the substrate and film. These dislocations tend to be mobile. When voids are present in the film and when the lattice misfit is low, dislocations tend to be trapped in the voids or pulled toward them due to dislocation image interactions. Once attached to voids, dislocations are effectively pinned there. When voids are absent or when the misfit is high, dislocations are restricted to the film-substrate interface. In the case of heteroepitaxy, dislocations are found to relieve either tensile or compressive misfit stresses. Misfit stresses may also be accommodated, to some extent, merely by the free volume of the voids themselves.

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Mechanisms of misfit strain relaxation in epitaxially grown BLT (Bi4-xLaxTi3O12, x = 0.75) thin films

MRS Proceedings ◽

10.1557/proc-779-w5.23 ◽

2003 ◽

Vol 779 ◽

Author(s):

Hyung Seok Kim ◽

Sang Ho Oh ◽

Ju Hyung Suh ◽

Chan Gyung Park

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Strain Relaxation ◽

Lattice Misfit ◽

Misfit Strain ◽

Misfit Dislocations ◽

Transmission Electron ◽

Means Of Transmission ◽

20 Nm

AbstractMechanisms of misfit strain relaxation in epitaxially grown Bi4-xLaxTi3O12 (BLT) thin films deposited on SrTiO3 (STO) and LaAlO3 (LAO) substrates have been investigated by means of transmission electron microscopy (TEM). The misfit strain of 20 nm thick BLT films grown on STO substrate was relaxed by forming misfit dislocations at the interface. However, cracks were observed in 100 nm thick BLT films grown on the same STO. It was confirmed that cracks were formed because of high misfit strain accumulated with increasing the thickness of BLT, that was not sufficiently relaxed by misfit dislocations. In the case of the BLT film grown on LAO substrate, the magnitude of lattice misfit between BLT and LAO was very small (~1/10) in comparison with the case of the BLT grown on STO. The relatively small misfit strain formed in layered structure of the BLT films on LAO, therefore, was easily relaxed by distorting the film, rather than forming misfit dislocations or cracks, resulting in misorientation regions in the BLT film.

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Evaluation of the Stability of Raft Structure in Nickel Base Superalloys Throughout their Lifetime

MRS Proceedings ◽

10.1557/proc-980-0980-ii08-08 ◽

2006 ◽

Vol 980 ◽

Author(s):

Katsushi Tanaka ◽

Toru Inoue ◽

Tetsu Ichitsubo ◽

Kyosuke Kishida ◽

Haruyuki Inui

Keyword(s):

Strain Energy ◽

Lattice Misfit ◽

Gamma Prime ◽

Lamellar Interface ◽

Nickel Base Superalloys ◽

Nickel Base ◽

The Stability ◽

Numerical Calculation Method ◽

Creep Deformations ◽

Lamellar Interfaces

AbstractStability of raft structure in nickel base superalloys has been examined by using elastic energy calculations based on a microelasticity theory. The numerical calculation method for a structurally heterogeneous system is applied. The results indicate that the raft structure is significantly stabilized by introductions of creep deformations till the critical creep deformation at which the lattice misfit between gamma and gamma-prime phases is completely compensated by creep dislocations. When the magnitude of creep deformations exceed the critical value, the (001) lamellar interfaces become elastically unstable and a tilted lamellar interface become the most stable one. This instability of the 001 raft structure leads a tilted or wavy lamellar interfaces for reducing the internal strain energy, that is a precursor to collapse the raft structure.

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Microscratch analysis of the work of adhesion for Pt thin films on NiO

Journal of Materials Research ◽

10.1557/jmr.1992.1126 ◽

1992 ◽

Vol 7 (5) ◽

pp. 1126-1132 ◽

Cited By ~ 72

Author(s):

S. Venkataraman ◽

D.L. Kohlstedt ◽

W.W. Gerberich

Keyword(s):

Thin Films ◽

Strain Energy ◽

Reasonable Agreement ◽

Sample Surface ◽

Work Of Adhesion ◽

Elastic Contact ◽

Interfacial Fracture Toughness ◽

Load Drop ◽

Metal Ceramic ◽

Scratch Track

The adhesion of as-sputtered Pt thin films to NiO single crystals has been characterized by a continuous microscratch technique. In these experiments, a conical indenter was driven into a 1.2 μm thick Pt film at a rate of 15 nm/s, and across the sample surface at a rate of 0.5 μm/s, until a load drop was observed indicating that the film had delaminated. Using the width of the scratch track at the point at which the film delaminated from the substrate, the critical load required for delamination, and the area of the delaminated region, a model has been developed to determine the work of adhesion of the Pt/NiO system. This model uses an elastic contact mechanics approach to relate the stresses acting in a scratch experiment to the strain energy released during film delamination. Using this model, the work of adhesion and hence the interfacial fracture toughness have been determined to be 0.023–0.06 J/m2 and 0.07–0.11 MPa$\sqrt m$, respectively. These values are in reasonable agreement with those determined by other methods for metal-ceramic systems.

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Energy Minimization During Epitaxial Grain Growth: Strain VS. Interfacial Energy

MRS Proceedings ◽

10.1557/proc-317-419 ◽

1993 ◽

Vol 317 ◽

Cited By ~ 1

Author(s):

J. A. Floro ◽

R. Carel ◽

C. V. Thompson

Keyword(s):

Grain Growth ◽

Interfacial Energy ◽

Energy Minimization ◽

Strain Energy ◽

Elastic Anisotropy ◽

Interface Energy ◽

Growth Strain ◽

Free Energies ◽

Film Substrate ◽

Epitaxial Grain Growth

ABSTRACTWe have investigated Epitaxial Grain Growth (EGG) in polycrystalline Ag films on Ni (001) substrates. EGG is driven by minimization of crystallographically anisotropie free energies such as the film/substrate interfacial energy and the film strain. Under some conditions EGG results in the preferred growth of the (111) epitaxial orientations that are predicted to minimize the interfacial energy. However, when Ag films are deposited on Ni (001) at low temperature, EGG experiments consistently find that (111) oriented grains are consumed by grains with (001) orientations predicted to have much higher interface and surface energy. The large elastic anisotropy of Ag can account for this discrepancy. The film thickness and the deposition temperature (relative to the grain growth temperature) determine whether strain energy or interface energy minimization dominates orientation evolution during grain growth.

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