Magnetization processes and magnetic domain structures in ta/cofeb/mgo stacks

The high voltage Lorentz microscopy was successfully used to observe changes with temperature; of domain structures and metallurgical structures in an iron film set on the hot stage combined with a goniometer. The microscope used was the JEM-1000 EM which was operated with the objective lens current cut off to eliminate the magnetic field in the specimen position. Single crystal films with an (001) plane were prepared by the epitaxial growth of evaporated iron on a cleaved (001) plane of a rocksalt substrate. They had a uniform thickness from 1000 to 7000 Å.The figure shows the temperature dependence of magnetic domain structure with its corresponding deflection pattern and metallurgical structure observed in a 4500 Å iron film. In general, with increase of temperature, the straight domain walls decrease in their width (at 400°C), curve in an iregular shape (600°C) and then vanish (790°C). The ripple structures with cross-tie walls are observed below the Curie temperature.

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Highlights in the history of X-ray topography1

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1995.210.6.394 ◽

1995 ◽

Vol 210 (6) ◽

Author(s):

A. R. Lang

Keyword(s):

Magnetic Domain ◽

Diffraction Theory ◽

Dislocation Loops ◽

X Ray Diffraction ◽

X Ray ◽

Domain Structures ◽

Structure Factors ◽

History Of ◽

Dislocation Sources ◽

Non Destructive

AbstractX-ray topography provides a non-destructive method of mapping point-by-point variations in orientation and reflecting power within crystals. The discovery, made by several workers independently, that in nearly perfect crystals it was possible to detect individual dislocations by X-ray diffraction contrast started an epoch of rapid exploitation of X-ray topography as a new, general method for assessing crystal perfection. Another discovery, that of X-ray Pendellösung, led to important theoretical developments in X-ray diffraction theory and to a new and precise method for measuring structure factors on an absolute scale. Other highlights picked out for mention are studies of Frank-Read dislocation sources, the discovery of long dislocation helices and lines of coaxial dislocation loops in aluminium, of internal magnetic domain structures in Fe-3 wt.% Si, and of stacking faults in silicon and natural diamonds.

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Magnetic properties of (Bi1−xLax)(Fe,Co)O3 films fabricated by a pulsed DC reactive sputtering and demonstration of magnetization reversal by electric field

Scientific Reports ◽

10.1038/s41598-021-90547-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Munusamy Kuppan ◽

Daichi Yamamoto ◽

Genta Egawa ◽

Sivaperuman Kalainathan ◽

Satoru Yoshimura

Keyword(s):

Electric Field ◽

Magnetization Reversal ◽

High Performance ◽

Magnetic Domain ◽

Magnetic Film ◽

Film Plane ◽

Force Microscopy ◽

Domain Structures ◽

Pulsed Dc ◽

Submicron Scale

Abstract(Bi1−xLax)(Fe,Co)O3 multiferroic magnetic film were fabricated using pulsed DC (direct current) sputtering technique and demonstrated magnetization reversal by applied electric field. The fabricated (Bi0.41La0.59)(Fe0.75Co0.25)O3 films exhibited hysteresis curves of both ferromagnetic and ferroelectric behavior. The saturated magnetization (Ms) of the multiferroic film was about 70 emu/cm3. The squareness (S) (= remanent magnetization (Mr)/Ms) and coercivity (Hc) of perpendicular to film plane are 0.64 and 4.2 kOe which are larger compared with films in parallel to film plane of 0.5 and 2.5 kOe. The electric and magnetic domain structures of the (Bi0.41La0.59)(Fe0.75Co0.25)O3 film analyzed by electric force microscopy (EFM) and magnetic force microscopy (MFM) were clearly induced with submicron scale by applying a local electric field. This magnetization reversal indicates the future realization of high performance magnetic device with low power consumption.

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Magnetic domain structures in multilayered NiFe films

Journal of Applied Physics ◽

10.1063/1.326960 ◽

1979 ◽

Vol 50 (B3) ◽

pp. 2384-2386 ◽

Cited By ~ 31

Author(s):

S. R. Herd ◽

K. Y. Ahn

Keyword(s):

Magnetic Domain ◽

Domain Structures

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Magnetic domain structures and stray fields of individual elongated magnetite grains revealed by magnetic force microscopy (MFM)

Physics of The Earth and Planetary Interiors ◽

10.1016/j.pepi.2003.12.001 ◽

2004 ◽

Vol 141 (2) ◽

pp. 121-129 ◽

Cited By ~ 27

Author(s):

C. Frandsen ◽

S.L.S. Stipp ◽

S.A. McEnroe ◽

M.B. Madsen ◽

J.M. Knudsen

Keyword(s):

Magnetic Force Microscopy ◽

Magnetic Force ◽

Magnetic Domain ◽

Force Microscopy ◽

Domain Structures

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The Influences of Depositing Angles on TbFe Film Magnetic and Magnetostrictive Characteristics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3757 ◽

2005 ◽

Vol 475-479 ◽

pp. 3757-3760

Author(s):

Hong Chuan Jiang ◽

Wan Li Zhang ◽

Bin Peng ◽

Wen Xu Zhang ◽

Shi Qing Yang

Keyword(s):

External Field ◽

Magnetic Domain ◽

Grain Morphology ◽

Dc Magnetron Sputtering ◽

Easy Magnetization ◽

Magnetization Direction ◽

Saturation Field ◽

Domain Structures ◽

Columnar Grain ◽

Easy Magnetization Direction

In this paper, the influences of depositing angles on TbFe film magnetic and magnetostrictive characteristics were discussed. TbFe films were deposited by DC magnetron sputtering. With the decrease of depositing angles from 900 to 150, TbFe film in-plane magnetization measured at 1600kA.m-1 external field is greatly increased. With the decrease of depositing angles from 900 to 150, the magnetostrictive saturation field is decreased. TbFe film in-plane magnetostriction is improved when depositing angles are changed from 900 to 150. Magnetic domain structures detected by MFM indicates that film easy magnetization direction is gradually changed from perpendicular to parallel with the decrease of depositing angles. The variation of film magnetic and magnetostrictive performances can be explained by the oblique anisotropy associated with columnar grain morphology of the films.

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