Magnetic behavior measurements under high frequency mechanical solicitations

We report the synthesis, crystal structure and magnetic properties of the new heptacoordinated mononuclear erbium(III) complex (Et3NH)[Er(H2DAPS)Cl2] (H4DAPS = 2,6-diacetylpyridine bis-(salicylhydrazone)) (1). The coordination polyhedron around the Er(III) ion figures...

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Enhanced thermal-operating stability of high-frequency magnetic behavior for FeMnSiBNbCu nano-structural cores via field-annealing

Vacuum ◽

10.1016/j.vacuum.2021.110214 ◽

2021 ◽

Vol 188 ◽

pp. 110214

Author(s):

Fuyao Yang ◽

Bojun Zhang ◽

Sida Man ◽

Guang Ma ◽

Xin Chen ◽

...

Keyword(s):

High Frequency ◽

Magnetic Behavior ◽

Thermal Operating ◽

Operating Stability ◽

Field Annealing

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High Frequency Magnetic Behavior of FeCoNiMnxAl1-x High-entropy Alloys Regulated by Ferromagnetic Transformation

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.163428 ◽

2021 ◽

pp. 163428

Author(s):

Yuping Duan ◽

Xingyang Sun ◽

Zerui Li ◽

Guojia Ma ◽

Qingtao Yu ◽

...

Keyword(s):

High Frequency ◽

Magnetic Behavior ◽

High Entropy Alloys ◽

High Entropy

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High-resolution magnetooptic imaging of the high-frequency magnetic behavior of ferrite recording heads

IEEE Transactions on Magnetics ◽

10.1109/20.101122 ◽

1991 ◽

Vol 27 (1) ◽

pp. 724-725 ◽

Cited By ~ 1

Author(s):

P.V. Koeppe ◽

M.H. Kryder

Keyword(s):

High Resolution ◽

High Frequency ◽

Magnetic Behavior ◽

Recording Heads

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High frequency magnetic behavior through the magnetoimpedance effect in CoFeB/(Ta, Ag, Cu) multilayered ferromagnetic thin films

Thin Solid Films ◽

10.1016/j.tsf.2011.10.028 ◽

2012 ◽

Vol 520 (6) ◽

pp. 2173-2177 ◽

Cited By ~ 12

Author(s):

M.S. Marques ◽

T.J.A. Mori ◽

L.F. Schelp ◽

C. Chesman ◽

F. Bohn ◽

...

Keyword(s):

Thin Films ◽

High Frequency ◽

Magnetic Behavior ◽

Ferromagnetic Thin Films

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Lorentz electron microscopy of magnetic domains in rapidly solidified and annealed Pt-Co-B alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088233 ◽

1991 ◽

Vol 49 ◽

pp. 784-785

Author(s):

N. Qiu ◽

J. E. Wittig

Keyword(s):

Rapid Solidification ◽

Ion Beam ◽

Magnetic Behavior ◽

High Coercivity ◽

Magnetic Domains ◽

Beam Angle ◽

Tem Analysis ◽

Intrinsic Coercivity ◽

Hard Magnets ◽

Rapidly Solidified

PtCo hard magnets have specialized applications owing to their relatively high coercivity combined with corrosion resistance and ductility. Increased intrinsic coercivity has been recently obtained by rapid solidification processing of PtCo alloys containing boron. After rapid solidification by double anvil splat quenching and subsequent annealing for 30 minutes at 650°C, an alloy with composition Pt42Co45B13 (at.%) exhibited intrinsic coercivity up to 14kOe. This represents a significant improvement compared to the average coercivities in conventional binary PtCo alloys of 5 to 8 kOe.Rapidly solidified specimens of Pt42Co45B13 (at.%) were annealed at 650°C and 800°C for 30 minutes. The magnetic behavior was characterized by measuring the coercive force (Hc). Samples for TEM analysis were mechanically thinned to 100 μm, dimpled to about 30 nm, and ion milled to electron transparency in a Gatan Duomill at 5 kV and 1 mA gun current. The incident ion beam angle was set at 15° and the samples were liquid nitrogen cooled during milling. These samples were analyzed with a Philips CM20T TEM/STEM operated at 200 kV.

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The Microstructure of Steatite (Protoenstatite)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118102 ◽

1985 ◽

Vol 43 ◽

pp. 236-237

Author(s):

W. E. Lee ◽

A. H. Heuer

Keyword(s):

High Frequency ◽

Glass Ceramics ◽

Magnesium Silicate ◽

Beam Current ◽

Glassy Matrix ◽

Angle Of Incidence ◽

X Ray ◽

Mechanical And Electrical Properties ◽

Argon Ions ◽

High Temperature Polymorph

IntroductionTraditional steatite ceramics, made by firing (vitrifying) hydrous magnesium silicate, have long been used as insulators for high frequency applications due to their excellent mechanical and electrical properties. Early x-ray and optical analysis of steatites showed that they were composed largely of protoenstatite (MgSiO3) in a glassy matrix. Recent studies of enstatite-containing glass ceramics have revived interest in the polymorphism of enstatite. Three polymorphs exist, two with orthorhombic and one with monoclinic symmetry (ortho, proto and clino enstatite, respectively). Steatite ceramics are of particular interest a they contain the normally unstable high-temperature polymorph, protoenstatite.Experimental3mm diameter discs cut from steatite rods (∼10” long and 0.5” dia.) were ground, polished, dimpled, and ion-thinned to electron transparency using 6KV Argon ions at a beam current of 1 x 10-3 A and a 12° angle of incidence. The discs were coated with carbon prior to TEM examination to minimize charging effects.

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Simulations of high-resolution images of amorphous silicon films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014419x ◽

1986 ◽

Vol 44 ◽

pp. 544-545

Author(s):

G. Y. Fan ◽

J. M. Cowley

Keyword(s):

Electron Microscope ◽

High Frequency ◽

Fourier Transformation ◽

Amorphous Materials ◽

Low Frequency ◽

Chromatic Aberration ◽

Structure Information ◽

Frequency Components ◽

High Resolution Images ◽

Spatial Frequency Spectrum

It is well known that the structure information on the specimen is not always faithfully transferred through the electron microscope. Firstly, the spatial frequency spectrum is modulated by the transfer function (TF) at the focal plane. Secondly, the spectrum suffers high frequency cut-off by the aperture (or effectively damping terms such as chromatic aberration). While these do not have essential effect on imaging crystal periodicity as long as the low order Bragg spots are inside the aperture, although the contrast may be reversed, they may change the appearance of images of amorphous materials completely. Because the spectrum of amorphous materials is continuous, modulation of it emphasizes some components while weakening others. Especially the cut-off of high frequency components, which contribute to amorphous image just as strongly as low frequency components can have a fundamental effect. This can be illustrated through computer simulation. Imaging of a whitenoise object with an electron microscope without TF limitation gives Fig. 1a, which is obtained by Fourier transformation of a constant amplitude combined with random phases generated by computer.

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SEM image sharpness analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163174 ◽

1996 ◽

Vol 54 ◽

pp. 142-143

Author(s):

M. T. Postek ◽

A. E. Vladar

Keyword(s):

High Frequency ◽

Low Frequency ◽

Quantitative Information ◽

Primary Electron ◽

Image Sharpness ◽

Critical Dimensions ◽

Sem Image ◽

Frequency Changes ◽

Electron Microscopes ◽

Scanning Electron

Fully automated or semi-automated scanning electron microscopes (SEM) are now commonly used in semiconductor production and other forms of manufacturing. The industry requires that an automated instrument must be routinely capable of 5 nm resolution (or better) at 1.0 kV accelerating voltage for the measurement of nominal 0.25-0.35 micrometer semiconductor critical dimensions. Testing and proving that the instrument is performing at this level on a day-by-day basis is an industry need and concern which has been the object of a study at NIST and the fundamentals and results are discussed in this paper.In scanning electron microscopy, two of the most important instrument parameters are the size and shape of the primary electron beam and any image taken in a scanning electron microscope is the result of the sample and electron probe interaction. The low frequency changes in the video signal, collected from the sample, contains information about the larger features and the high frequency changes carry information of finer details. The sharper the image, the larger the number of high frequency components making up that image. Fast Fourier Transform (FFT) analysis of an SEM image can be employed to provide qualitiative and ultimately quantitative information regarding the SEM image quality.

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