Intrinsic Stress and Microstructural Evolution in Sputtered Nanometer Single and Multilayered Films

1994 ◽  
Vol 343 ◽  
Author(s):  
Tai D. Nguyen
Keyword(s):  
Film Thickness ◽  
Microstructural Evolution ◽  
Thin Layers ◽  
Intrinsic Stress ◽  
Working Pressure ◽  
Compressive Stresses ◽  
Columnar Grain ◽  
Si Films ◽  
Relationship Of ◽  
The Relationship

ABSTRACTThe relationship of intrinsic stress and microstructural evolution in nanometer thick Mo and Si films, and Mo/Si multilayers deposited by magnetron sputtering at low working pressure (2.5 mTorr) is studied. The stress depends strongly on the microstructure which evolves with the film thickness. Transition from tensile to compressive films is observed in the metal films, in which nucleation and columnar grain growth occur. Deposition of layered Mo films by time-delayed sequential sputtering of thin layers results in smaller grains that do not extend through the film thickness, and in more tensile stress state than thick films of trie same thickness. The Si films are highly compressive at all thicknesses studied. The multilayers in this study show compressive stresses, with higher compressive stress at longer periods, and decreasing stress at shorter periods. The interface stress in amorphous Mo/Si multilayers is determined to be 1.1 J/m2. Comparison with values in other systems is made.

Stress, Microstructure, and Thermal Behavior in Mo/Si X-Ray Multilayers

1995 ◽  
Vol 382 ◽  
Author(s):  
Tai D. Nguyen ◽  
James H. Underwood
Keyword(s):  
Thermal Stress ◽  
Stress Relaxation ◽  
Magnetron Sputtering ◽  
Thermal Behavior ◽  
Microstructural Evolution ◽  
Intrinsic Stress ◽  
Working Pressure ◽  
X Ray ◽  
The Relationship

ABSTRACTThe relationship between intrinsic stress and microstructural evolution in nanometer Mo/Si multilayers deposited by magnetron sputtering at low working pressure (2.5 mTorr) is studied. The stress depends strongly on the microstructure which evolves with the multilayer period. In-situ thermal stress measurements show stress relaxation is observed in Mo/Si multilayers after annealing at 300°C in nitrogen ambient, due to microstructural changes in the multilayers. Average stress exhibits changes after annealing at 500°C which correspond to increased interdiffusion between the layer materials and crystallization at the interfaces.

Effect of Split-Sleeve Cold Expansion on the Fatigue Life of 7050-T7451 Aluminum Alloy

2014 ◽  
Vol 1082 ◽  
pp. 403-407 ◽  
Author(s):  
Hong Huang ◽  
Qing Yun Zhao ◽  
Feng Lei Liu
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Life ◽  
Residual Stresses ◽  
Transgranular Fracture ◽  
Alloy Plate ◽  
Cold Expansion ◽  
Compressive Stresses ◽  
Aluminum Alloy Plate ◽  
Relationship Of ◽  
The Relationship

Split-sleeve cold expansion processing was employed on the 7050-T7451 aluminum alloy plate. Fatigue lives were compared according different expansion, then the relationship of fatigue life and expansion was analyzed. Residual stresses were measured with different expansion, and the fatigue fractograph was analyzed by SEM. The results show that the split-sleeve cold expansion can obtain longer life compared with the non-strengthen hole. When over the optimum expansion, fatigue life began to decrease. The maximum fatigue life increased to 2.92 times with 4.1% expansion. The maximum values of radial residual stresses grew with expansion. The depths of residual compressive stresses were more than 6mm with 2.6% and 4.1% expansion. The fatigue fractograph shows mixed transgranular fracture.

Study on Relationship of Ink Thickness and Color Saturation

2015 ◽  
Vol 731 ◽  
pp. 295-299
Author(s):  
Ye Chi Pang ◽  
Zhi Jie Li ◽  
Li Lin Shi
Keyword(s):  
Film Thickness ◽  
Layer Thickness ◽  
Inflection Point ◽  
Measured Data ◽  
Complex Spectrum ◽  
Offset Printing ◽  
Color Saturation ◽  
Color Quality ◽  
Relationship Of ◽  
The Relationship

In the offset printing process, the amount of ink supplying of fountain directly affects plate ink thickness, thereby affecting the color quality on the printed sheet. Ink layer thickness is difficult to judge by human eye, but we can regulate the ink thickness by detecting the color saturation. This paper describes using complex spectrum spectrometer measured data ink layer thickness and color saturation, draw two graphs of complex spectrum saturation and CIE saturation. Due to the different definitions of saturation, Cause their sensitivity of layer thickness changes response different. Two sets of data shows that the complex spectrum saturation contrast ΔS1 significantly higher than CIE saturation contrast. The data also showed that the ink color performance in terms of the relationship between layer thickness and saturation has an inflection point, the inflection point in the ink film thickness about 4μm, after reaching inflection point, even if the ink layer thickness continues to increase, there will be no significant changes in the saturation.

Relationship between domain structure and film thickness in epitaxial PbTiO3 films deposited on MgO(001) by reactive sputtering

1999 ◽  
Vol 14 (12) ◽  
pp. 4677-4684 ◽  
Author(s):  
Won Kyoung Choi ◽  
Si Kyoung Choi ◽  
Hyuck Mo Lee
Keyword(s):  
Film Thickness ◽  
Domain Structure ◽  
Thermal Stresses ◽  
Volume Fraction ◽  
Intrinsic Stress ◽  
Composition Change ◽  
The Finite Element Method ◽  
X Ray ◽  
The Relationship ◽  
Different Thickness

The epitaxial PbTiO3 thin films of different thickness were prepared on MgO(001) substrates by the reactive direct-current magnetron sputtering. The volume fraction of c domains, α, which was measured by x-ray diffractometry, increased rapidly from zero with the film thickness, being saturated at about 90% above 100 nm. The films were annealed in a PbO atmosphere at 700 °C for 8 h, and they were used to study the composition change in the Pb/(Pb + Ti) ratio and the relaxation of the residual intrinsic stress. The relationship between change of α and composition was weak. The stress state was calculated through the finite-element method. As for the small thickness, the tensile epitaxial stress overwhelmed compressive intrinsic and thermal stresses, and the domain structure was a-domain oriented. As for the large thickness, the compressive intrinsic stress together with the thermal stress overcame the tensile epitaxial stress, and the population turned into c domain.

scholarly journals Microscopical Evaluation of Glass Delamination in Pharmaceutical Vials: A Look at Three Different Vial Manufacturers

2004 ◽  
Vol 12 (4) ◽  
pp. 28-33
Author(s):  
Kristie Diebold
Keyword(s):  
Quality Control ◽  
Chemical Nature ◽  
Medical Profession ◽  
Health Hazard ◽  
Pharmaceutical Product ◽  
Thin Layers ◽  
Regulatory Quality ◽  
Relationship Of ◽  
The Relationship ◽  
Surface Glass

Delamination is defined as separation into constituent thin layers (lamellae). Glass delamination, which can have several causes, could then be defined as a separation of surface glass, as from a vial, into thin layers resulting in a flaky appearance. Pitting could be related to, or even be the initial stages of glass delamination; data will be provided that supports a relationship. The presence of glass delamination is a serious concern to the pharmaceutical industry, not only because suspended glass flakes in any pharmaceutical product poses an obvious health hazard, but because of regulatory quality control standards, and medical profession requirements.There are, of course, many ways of addressing the problem of glass delamination in pharmaceutical vials, including looking into the relationship of chemical nature of vial contents to degree of delamination and conditions of vial manufacture. Specialized lighting and imaging methods are other research approaches.

A method to evaluate explosive crystallization velocity of amorphous silicon films during flash lamp annealing

2014 ◽  
Vol 92 (7/8) ◽  
pp. 718-722 ◽  
Author(s):  
Keisuke Ohdaira
Keyword(s):  
Film Thickness ◽  
Amorphous Silicon ◽  
High Speed ◽  
Flash Lamp ◽  
Periodic Modulation ◽  
Emission Frequency ◽  
Explosive Crystallization ◽  
Lateral Crystallization ◽  
Si Films ◽  
The Relationship

Flash lamp annealing (FLA) of micrometre-order thick amorphous silicon (a-Si) films can induce explosive crystallization (EC), high-speed lateral crystallization driven by the release of latent heat. We develop multipulse FLA system, which emits a quasi-millisecond pulse consisting of a number of subpulses. The emission frequency of the subpulses can be systematically controlled, and the emission of subpulses leads to the periodic modulation of the temperature of a Si film and the resulting formation of macroscopic stripe patterns. The relationship between a subpulse emission frequency and the width of the macroscopic stripe patterns yields EC velocity. Two kinds of EC modes can be observed, depending on the methods of precursor a-Si deposition and (or) a-Si film thickness.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Studies on Leukemogenic and Sarcomagenic Viruses

1970 ◽  
Vol 28 ◽  
pp. 156-157
Author(s):  
Leon Dmochowski
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Morphological Properties ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

1991 ◽  
Vol 49 ◽  
pp. 236-237
Author(s):  
J.R. Pfeiffer ◽  
J.C. Seagrave ◽  
C. Wofsy ◽  
J.M. Oliver
Keyword(s):  
Mast Cells ◽  
Protein A ◽  
Scattered Electron ◽  
Ige Receptor ◽  
Receptor Complexes ◽  
Ige Binding ◽  
Electron Imaging ◽  
Small Clusters ◽  
Relationship Of ◽  
The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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