526. Failure mechanism in thin films may work as transducer

Molecular dynamics study has been performed to investigate the effect of extreme dynamic loading condition on thin Nickel films. Due to the novel aspects of thin films, it has attracted attention over the years for Nano-electro-mechanical systems design. This would be helpful for the analysis of ultra short pulse laser induced fabrication or machining of thin films. Uniaxial high tensile strain namely 109 and 1010 s−1 has been used on a Nickel thin film. The Embedded-atom method (EAM) potential function for Nickel has been used for the interaction of the atoms. We have observed ductile failure mechanism on both the cases. With the increase of strain rate, not only high strength has been found but also the elastic modulus has been affected less. Random non spherical void growth and their coalescence have been also observed during higher loading condition which leads to a ductile failure mechanism.

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Delamination from edge flaws

Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences ◽

10.1098/rspa.1994.0140 ◽

1994 ◽

Vol 447 (1930) ◽

pp. 271-279 ◽

Cited By ~ 25

Keyword(s):

Thin Films ◽

Stress State ◽

Failure Mechanism ◽

Crack Front ◽

Failure Mechanisms ◽

Different Types ◽

Laminated Material ◽

Localized Failure

The mechanics of delamination from an edge flaw in a laminated material is presented. Two different types of failure mechanism have been identified: uniform delamination along the crack front and localized delamination which can be initiated if the laminate buckles above the debonded portion of the interface. Depending on the stress state within the bonded portion of the laminate, this localized failure can initiate the formation of blisters which grow by a mechanism of buckling-driven delamination and can cause general failure of the laminate. There are conditions under which this class of buckling-assisted delamination occurs at loads lower than would be predicted for uniform delamination. It may, therefore, have important implications in the design against failure for thin films, composites and other laminated systems. Experimental observations of the different failure mechanisms are presented and the factors governing the transitions between them are discussed.

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Failure mechanism of free standing single-walled carbon nanotube thin films under tensile load

Physical Chemistry Chemical Physics ◽

10.1039/b315300b ◽

2004 ◽

Vol 6 (13) ◽

pp. 3540-3544 ◽

Cited By ~ 24

Author(s):

Sharali Malik ◽

Harald Rösner ◽

Frank Hennrich ◽

Artur Böttcher ◽

Manfred M. Kappes ◽

...

Keyword(s):

Thin Films ◽

Carbon Nanotube ◽

Failure Mechanism ◽

Tensile Load ◽

Free Standing ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon

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Oxidation-induced electromigration failure of thin films of aluminium

Australian Journal of Chemistry ◽

10.1071/ch9722069 ◽

1972 ◽

Vol 25 (10) ◽

pp. 2069 ◽

Cited By ~ 2

Author(s):

LE Lyons ◽

W Riemer

Keyword(s):

Thin Films ◽

Failure Mechanism ◽

Current Density ◽

Atmospheric Pressure ◽

Oxide Thickness ◽

Initial Increase ◽

Film Resistance ◽

Resistance Increase ◽

Logarithmic Law ◽

Film Failure

The failure mechanism of very thin films (<10 nm) of aluminium exposed to oxygen at atmospheric pressure was investigated. At an apparent current density of 100 A cm-2 two distinct types of film resistance increase on oxidation were observed. During the initial increase, describable by the direct logarithmic law, the oxide thickness could be expressed in terms of the film resistance. The second resistance increase, leading to film failure, was consistent with electromigration induced by the thinning by oxidation of the cathode contact film junction.

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The study of interfacial reactions of nickel thin films on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074616 ◽

1983 ◽

Vol 41 ◽

pp. 156-157

Author(s):

L.J. Chen ◽

Y.F. Hsieh

Keyword(s):

Thin Films ◽

Integrated Circuits ◽

Interfacial Reactions ◽

Metal Contacts ◽

Nickel Thin Films ◽

Thin Foils ◽

The Status ◽

Si Doped ◽

Electron Microscopes

One measure of the maturity of a device technology is the ease and reliability of applying contact metallurgy. Compared to metal contact of silicon, the status of GaAs metallization is still at its primitive stage. With the advent of GaAs MESFET and integrated circuits, very stringent requirements were placed on their metal contacts. During the past few years, extensive researches have been conducted in the area of Au-Ge-Ni in order to lower contact resistances and improve uniformity. In this paper, we report the results of TEM study of interfacial reactions between Ni and GaAs as part of the attempt to understand the role of nickel in Au-Ge-Ni contact of GaAs.N-type, Si-doped, (001) oriented GaAs wafers, 15 mil in thickness, were grown by gradient-freeze method. Nickel thin films, 300Å in thickness, were e-gun deposited on GaAs wafers. The samples were then annealed in dry N2 in a 3-zone diffusion furnace at temperatures 200°C - 600°C for 5-180 minutes. Thin foils for TEM examinations were prepared by chemical polishing from the GaA.s side. TEM investigations were performed with JE0L- 100B and JE0L-200CX electron microscopes.

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Studies on Water in the Hydration Chamber of a Modified Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069715 ◽

1970 ◽

Vol 28 ◽

pp. 544-545

Author(s):

R. C. Moretz ◽

G. G. Hausner ◽

D. F. Parsons

Keyword(s):

Thin Film ◽

Thin Films ◽

Electron Microscope ◽

Steady State ◽

Room Temperature ◽

Small Mass ◽

Equilibrium Pressure ◽

Biological Objects ◽

Mechanical Pump ◽

Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

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Nucleation and Early Growth of Sputtered thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069570 ◽

1970 ◽

Vol 28 ◽

pp. 516-517

Author(s):

Dudley M. Sherman ◽

Thos. E. Hutchinson

Keyword(s):

Thin Films ◽

Electron Beam ◽

Ion Beam ◽

Ion Source ◽

Water Cooling ◽

Stages Of Growth ◽

Lens Assembly ◽

Microscope Technique ◽

Ion Beam Sputter Deposition

The in situ electron microscope technique has been shown to be a powerful method for investigating the nucleation and growth of thin films formed by vacuum vapor deposition. The nucleation and early stages of growth of metal deposits formed by ion beam sputter-deposition are now being studied by the in situ technique.A duoplasmatron ion source and lens assembly has been attached to one side of the universal chamber of an RCA EMU-4 microscope and a sputtering target inserted into the chamber from the opposite side. The material to be deposited, in disc form, is bonded to the end of an electrically isolated copper rod that has provisions for target water cooling. The ion beam is normal to the microscope electron beam and the target is placed adjacent to the electron beam above the specimen hot stage, as shown in Figure 1.

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Macromolecular structures of biological specimens are not obscured by controlled osmium impregnation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076639 ◽

1983 ◽

Vol 41 ◽

pp. 606-607

Author(s):

Klaus-Ruediger Peters ◽

Samuel A. Green

Keyword(s):

Thin Films ◽

Electrical Conductivity ◽

Critical Point ◽

Metal Films ◽

High Magnification ◽

Osmium Impregnation ◽

Instrumental Resolution ◽

20 Nm ◽

Continuous Metal

High magnification imaging of macromolecules on metal coated biological specimens is limited only by wet preparation procedures since recently obtained instrumental resolution allows visualization of topographic structures as smal l as 1-2 nm. Details of such dimensions may be visualized if continuous metal films with a thickness of 2 nm or less are applied. Such thin films give sufficient contrast in TEM as well as in SEM (SE-I image mode). The requisite increase in electrical conductivity for SEM of biological specimens is achieved through the use of ligand mediated wet osmiuum impregnation of the specimen before critical point (CP) drying. A commonly used ligand is thiocarbohvdrazide (TCH), first introduced to TEM for en block staining of lipids and glvcomacromolecules with osmium black. Now TCH is also used for SEM. However, after ligand mediated osinification nonspecific osmium black precipitates were often found obscuring surface details with large diffuse aggregates or with dense particular deposits, 2-20 nm in size. Thus, only low magnification work was considered possible after TCH appl ication.

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The Precipitation of Si in AlCuSi Thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070618 ◽

1973 ◽

Vol 31 ◽

pp. 34-35 ◽

Cited By ~ 1

Author(s):

R. M. Anderson

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Heat Treatment ◽

Solid Solution ◽

Integrated Circuit ◽

Copper Film ◽

Solution Concentration ◽

X Ray ◽

Silicon Thin Films ◽

Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

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