Direct Observation of Crack Propagation in Copper–Niobium Multilayers

The failure of a cross-sectional 65 nm-thick copper and 150 nm-thick niobium multilayer thin film was investigated via an in situ transmission electron microscopy straining experiment. The fracture of the free-standing multilayer films was associated with confined dislocation slip within layers containing and preceding the crack tip. Four crack hindrance mechanisms were observed to operate during crack propagation: microvoid formation, crack deviation, layer necking, and crack blunting. Failure was observed to occur across and through the copper and niobium layers but never within the interfaces or grain boundaries. These results are discussed relative to the length-scale-dependent deformation mechanisms of nanoscale metallic multilayers.

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Mechanisms of Grain Growth in Free-Standing Nanograined Gold Thin Films

MRS Proceedings ◽

10.1557/proc-0907-mm06-03 ◽

2005 ◽

Vol 907 ◽

Cited By ~ 1

Author(s):

J. A. Gregg ◽

K Hattar ◽

C H Lei ◽

I M Robertson

Keyword(s):

Thin Films ◽

Grain Growth ◽

Structural Changes ◽

Dislocation Slip ◽

Free Standing ◽

Transmission Electron ◽

Enhanced Properties ◽

Gold Thin Films ◽

Annealing Experiments

AbstractRetention of the enhanced properties reported for nanograined metallic systems requires that the nanostructure be insensitive to temperature and deformation. In situ transmission electron microscopy annealing experiments were employed to investigate the structural changes associated with the formation of micron-sized grains in nanograined evaporated gold thin films. This abnormal grain growth occurs randomly throughout the film. Twinning but not dislocation slip occurs in the growing grains until the grain size is in the hundreds of nanometer range. The twins appear to hinder growth and for grain growth to continue the twins must either be annihilated or be able to grow with the grain concurrently.

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Direct Observations of Confined Layer Slip in Cu/Nb Multilayers

Microscopy and Microanalysis ◽

10.1017/s143192761200133x ◽

2012 ◽

Vol 18 (5) ◽

pp. 1155-1162 ◽

Cited By ~ 68

Author(s):

Nan Li ◽

Jian Wang ◽

Amit Misra ◽

Jian Yu Huang

Keyword(s):

Metallic Multilayers ◽

Dislocation Glide ◽

Direct Observations ◽

Transmission Electron ◽

Dominant Deformation Mechanism ◽

Deformation Work ◽

20 Nm ◽

Nanoscale Metallic Multilayers ◽

Mechanisms Of Deformation

AbstractIn situ nanoindentation of a 30 nm Cu/20 nm Nb multilayer film in a transmission electron microscope revealed confined layer slip as the dominant deformation mechanism. Dislocations were observed to nucleate from the Cu-Nb interfaces in both layers. Dislocation glide was confined by interfaces to occur within each layer, without transmission across interfaces. Cu and Nb layers co-deformed to large plastic strains without cracking. These microscopy observations provide insights in the unit mechanisms of deformation, work hardening, and recovery in nanoscale metallic multilayers.

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In Situ High Voltage Electron Microscopy Observations of Deformation and Fracture in Multilayered Materials

MRS Proceedings ◽

10.1557/proc-404-43 ◽

1995 ◽

Vol 404 ◽

Cited By ~ 1

Author(s):

M. A. Wall ◽

T. W. Barbee ◽

T. P. Weihs

Keyword(s):

Crack Nucleation ◽

Free Standing ◽

Cross Sectional ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Transmission Electron ◽

Deformation And Fracture ◽

Gauge Section ◽

Multilayered Materials

AbstractA novel, in situ transmission electron microcopy technique for the direct observation of deformation and fracture in multilayered materials oriented in cross-section is reviewed. Cross-sectional tensile specimens were prepared from thick, free-standing, Cu/Zr and Al/Ti multilayered foils. These tensile specimens contain a micro-gauge section, thus predetermining the location at which dislocation activity and crack nucleation and growth can be observed at high magnifications in the transmission electron microscope. The results from these experiments are unique and cannot be realized by any other technique. These observations will aid us in our understanding of the micromechanisms of deformation and fracture in multilayered materials.

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A New Method of Wafer Level Plan View TEM Sample Preparation by DualBeam

ISTFA 2008: Conference Proceedings from the 34th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2008p0168 ◽

2008 ◽

Author(s):

Hyoung H. Kang ◽

Michael A. Gribelyuk ◽

Oliver D. Patterson ◽

Steven B. Herschbein ◽

Corey Senowitz

Keyword(s):

Sample Preparation ◽

Ex Situ ◽

Wafer Level ◽

Cross Sectional ◽

Plan View ◽

Manufacturing Line ◽

Transmission Electron ◽

Thin Lamella ◽

Preparation Techniques

Abstract Cross-sectional style transmission electron microscopy (TEM) sample preparation techniques by DualBeam (SEM/FIB) systems are widely used in both laboratory and manufacturing lines with either in-situ or ex-situ lift out methods. By contrast, however, the plan view TEM sample has only been prepared in the laboratory environment, and only after breaking the wafer. This paper introduces a novel methodology for in-line, plan view TEM sample preparation at the 300mm wafer level that does not require breaking the wafer. It also presents the benefit of the technique on electrically short defects. The methodology of thin lamella TEM sample preparation for plan view work in two different tool configurations is also presented. The detailed procedure of thin lamella sample preparation is also described. In-line, full wafer plan view (S)TEM provides a quick turn around solution for defect analysis in the manufacturing line.

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Fracture in Bulk Amorphous Alloys

MRS Proceedings ◽

10.1557/proc-554-185 ◽

1998 ◽

Vol 554 ◽

Cited By ~ 5

Author(s):

J. A. Horton ◽

J. L. Wright ◽

J. H. Schneibel

Keyword(s):

Crack Propagation ◽

Crack Growth ◽

Shear Bands ◽

Bulk Amorphous Alloy ◽

In Situ Tem ◽

X Ray Diffraction ◽

Transmission Electron ◽

Crack Tips ◽

Temperature Fracture

AbstractThe fracture behavior of a Zr-based bulk amorphous alloy, Zr-10 Al-5 Ti-17.9 Cu-14.6Ni (at.%), was examined by transmission electron microscopy (TEM) and x-ray diffraction forany evidence of crystallization preceding crack propagation. No evidence for crystallizationwas found in shear bands in compression specimens or at the fracture surface in tensile specimens.In- situ TEM deformation experiments were performed to more closely examine actualcrack tip regions. During the in-situ deformation experiment, controlled crack growth occurredto the point where the specimen was approximately 20 μm thick at which point uncontrolledcrack growth occurred. No evidence of any crystallization was found at the crack tips or thecrack flanks. Subsequent scanning microscope examination showed that the uncontrolledcrack growth region exhibited ridges and veins that appeared to have resulted from melting. Performing the deformations, both bulk and in-situ TEM, at liquid nitrogen temperatures (LN2) resulted in an increase in the amount of controlled crack growth. The surface roughness of the bulk regions fractured at LN2 temperatures corresponded with the roughness of the crack propagation observed during the in-situ TEM experiment, suggesting that the smooth-appearing room temperature fracture surfaces may also be a result of localized melting.

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Oxidation Kinetics of Cu-Ni Alloy Observed by in situ UHV-TEM

MRS Proceedings ◽

10.1557/proc-1026-c05-03 ◽

2007 ◽

Vol 1026 ◽

Author(s):

Li Sun ◽

John E. Pearson ◽

Judith C. Yang

Keyword(s):

High Vacuum ◽

Alloy Film ◽

Ultra High Vacuum ◽

Cross Sectional ◽

Primary Mechanism ◽

Transmission Electron ◽

Ni Alloy ◽

Cu Oxidation ◽

Kinetics Of

AbstractThe nucleation and growth of Cu2O and NiO islands due to oxidation of Cu-24%Ni(001) films were monitored at various temperatures by in situ ultra-high vacuum (UHV) transmission electron microscopy (TEM). In remarkable contrast to our previous observations of Cu and Cu-Au oxidation, irregular-shaped polycrystalline oxide islands were observed to form with respect to the Cu-Ni alloy film, and an unusual second oxide nucleation stage was noted. Similar to Cu oxidation, the cross-sectional area growth rate of the oxide island is linear indicating oxygen surface diffusion is the primary mechanism of oxide growth.

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Single Crystal Silicon Carbide On Silicon Using A Supersonic Gas Jet Of Methylsilane

MRS Proceedings ◽

10.1557/proc-483-279 ◽

1997 ◽

Vol 483 ◽

Cited By ~ 1

Author(s):

S. A. Ustin ◽

C. Long ◽

L. Lauhon ◽

W. Ho

Keyword(s):

Growth Rate ◽

Growth Rates ◽

Single Crystal Silicon ◽

Maximum Growth ◽

X Ray Diffraction ◽

Crystal Silicon ◽

Cross Sectional ◽

Supersonic Molecular Beam ◽

Transmission Electron

AbstractCubic SiC films have been grown on Si(001) and Si(111) substrates at temperatures between 600 °C and 900 °C with a single supersonic molecular beam source. Methylsilane (H3SiCH3) was used as the sole precursor with hydrogen and nitrogen as seeding gases. Optical reflectance was used to monitor in situ growth rate and macroscopic roughness. The growth rate of SiC was found to depend strongly on substrate orientation, methylsilane kinetic energy, and growth temperature. Growth rates were 1.5 to 2 times greater on Si(111) than on Si(001). The maximum growth rates achieved were 0.63 μm/hr on Si(111) and 0.375μm/hr on Si(001). Transmission electron diffraction (TED) and x-ray diffraction (XRD) were used for structural characterization. In-plane azimuthal (ø-) scans show that films on Si(001) have the correct 4-fold symmetry and that films on Si(111) have a 6-fold symmetry. The 6-fold symmetry indicates that stacking has occurred in two different sequences and double positioning boundaries have been formed. The minimum rocking curve width for SiC on Si(001) and Si(111) is 1.2°. Fourier Transform Infrared (FTIR) absorption was performed to discern the chemical bonding. Cross Sectional Transmission Electron Microscopy (XTEM) was used to image the SiC/Si interface.

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