Sites for the free valence electrons in metallic alloys of the gamma brass type

We wish to report in this paper measurements of the inelastic scattering component due to the collective excitations (plasmons) and single particlehole excitations of the valence electrons in Al. Such scattering contributes to the diffuse electronic scattering seen in electron diffraction patterns and has recently been considered of significance in weak-beam images (see Gai and Howie) . A major problem in the determination of such scattering is the proper correction for multiple scattering. We outline here a procedure which we believe suitably deals with such problems and report the observed single scattering spectrum.In principle, one can use the procedure of Misell and Jones—suitably generalized to three dimensions (qx, qy and #x2206;E)--to derive single scattering profiles. However, such a computation becomes prohibitively large if applied in a brute force fashion since the quasi-elastic scattering (and associated multiple electronic scattering) extends to much larger angles than the multiple electronic scattering on its own.

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Valence state analysis of elements by EPMA and its application

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134752 ◽

1990 ◽

Vol 48 (2) ◽

pp. 230-231

Author(s):

Chen Liqing ◽

Liu Zuqin ◽

Zhang Wei

Keyword(s):

Valence State ◽

Line Intensities ◽

Valence States ◽

Valence Electrons ◽

Fe And Mn ◽

Intensity Ratios ◽

State Analysis

Valence state analyses of Fe and Mn in oxides by EPMA have been reported in literature. In this paper, the effects of valence state on intensity ratios ILα/IKα and ILα/ILβ of Cu, Ni, Co, Fe, Mn, Cr and their oxides, and on intensity ratios ILβ2/ILα1 and ILγ1/ILα1 of Mo, Nb, Zr and their oxides were studied. It was observed that intensity ratios change with valence states in accordance with some regularities, and these effects could be utilized for analyzing the valence states of catalysts.Valence state analysis of elements by EPMA is based on the fact that changes in the states of valence electrons in the outer shells of an atom cause corresponding changes in line intensities. The M electrons of Cu, Ni, Co, Fe, Mn, Cr and the N electrons of Mo, Nb, Zr are valence electrons. Line Kα1,2 and six lines of L are produced from the transitions of K-L2,3 and L-M or L-N respectively.

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TEM study of amorphization of Cu and Ti foils by cold-rolling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173868 ◽

1990 ◽

Vol 48 (4) ◽

pp. 146-147

Author(s):

W. A. Chiou ◽

N. L. Jeon ◽

Genbao Xu ◽

M. Meshii

Keyword(s):

Solid State ◽

Cold Rolling ◽

High Energy ◽

Rapid Quenching ◽

Vapor Condensation ◽

Metallic Alloys ◽

Solid State Reactions ◽

High Energy Particle ◽

Amorphous Metallic Alloys ◽

Thin Foils

For many years amorphous metallic alloys have been prepared by rapid quenching techniques such as vapor condensation or melt quenching. Recently, solid-state reactions have shown to be an alternative for synthesizing amorphous metallic alloys. While solid-state amorphization by ball milling and high energy particle irradiation have been investigated extensively, the growth of amorphous phase by cold-rolling has been limited. This paper presents a morphological and structural study of amorphization of Cu and Ti foils by rolling.Samples of high purity Cu (99.999%) and Ti (99.99%) foils with a thickness of 0.025 mm were used as starting materials. These thin foils were cut to 5 cm (w) × 10 cm (1), and the surface was cleaned with acetone. A total of twenty alternatively stacked Cu and Ti foils were then rolled. Composite layers following each rolling pass were cleaned with acetone, cut into half and stacked together, and then rolled again.

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On the cohesion of covalent structures of elements in condensed phases. II. — corrections to a simple Hückel approximation due to coulomb interactions between valence electrons

Journal de Physique ◽

10.1051/jphys:01978003906067100 ◽

1978 ◽

Vol 39 (6) ◽

pp. 671-688 ◽

Cited By ~ 11

Author(s):

J. Friedel

Keyword(s):

Condensed Phases ◽

Coulomb Interactions ◽

Valence Electrons

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ELECTRONIC STRUCTURE OF AMORPHOUS Co-P AND Ni-P METALLIC ALLOYS : EVIDENCE FOR SHORT-RANGE ORDER

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19808107 ◽

1980 ◽

Vol 41 (C8) ◽

pp. C8-430-C8-432 ◽

Cited By ~ 6

Author(s):

J. Rivory ◽

B. Bouchet ◽

Y. Bertrand

Keyword(s):

Electronic Structure ◽

Short Range ◽

Short Range Order ◽

Metallic Alloys ◽

Range Order

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A multiscale strategy for first-principles virtual design of precipitation-hardened metallic alloys

10.26226/morressier.5f5f8e69aa777f8ba5bd5f4f ◽

2020 ◽

Author(s):

Javier LLorca

Keyword(s):

First Principles ◽

Metallic Alloys ◽

Virtual Design

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A Latent Issue of Via Resistance: Mechanism and Solution

10.31399/asm.cp.istfa2018p0121 ◽

2018 ◽

Author(s):

Wentao Qin ◽

Scott Donaldson ◽

Dan Rogers ◽

Lahcen Boukhanfra ◽

Julien Thiefain ◽

...

Keyword(s):

Thermal Stress ◽

Chemical Mechanical Planarization ◽

Resistance Mechanism ◽

Formation Enthalpy ◽

Metal Line ◽

Device Failure ◽

Valence Electrons ◽

Wafer Processing ◽

Field Failure ◽

And Tungsten

Abstract Many semiconductor products are manufactured with mature technologies involving the uses of aluminum (Al) lines and tungsten (W) vias. High resistances of the vias were sometimes observed only after electrical or thermal stress. A layer of Ti oxide was found on such a via. In the wafer processing, the post W chemical mechanical planarization (WCMP) cleaning left residual W oxide on the W plugs. Ti from the overlaying metal line spontaneously reduced the W oxide, through which Ti oxide formed. Compared with W oxide, the Ti oxide has a larger formation enthalpy, and the valence electrons of Ti are more tightly bound to the O ion cores. As a result, the Ti oxide is more resistive than the W oxide. Consequently, the die functioned well in the first test in the fab, but the via resistance increased significantly after a thermal stress, which led to device failure in the second test. The NH4OH concentration was therefore increased to more effectively remove residual W oxide, which solved the problem. The thermal stress had prevented the latent issue from becoming a more costly field failure.

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