Estimation of Magnetic Energy Distribution in Co84Cr16Ta4 Magnetic Thin Films from EFTEM

AbstractMagnetic thin films of Co80Cr16Ta4 were sputtered onto identical CrMo seed-layers at −200 V bias and 3 different substrate temperatures (150, 200, and 250°C). Energy-filtered transmission electron microscopy (EFTEM) was performed to analyze Cr levels at the grain boundaries as well as inside the grains. These quantitative Cr measurements were used to estimate the local values of magnetocrystalline anisotropy (Ku) and, together with grain size distributions, calculate the product of Ku and the grain volume (KuV), a quantity which is a measure of thermal stability. The results show that the coercivity as well as the percentage of stable grains increased with increasing substrate temperature. The increase in the number of stable grains is produced by the enhancement in the Ku value from Cr depletion of the grain interiors and the magnetic decoupling between the grains from Cr grain boundary segregation.

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Grain Growth in Al-(Cu, Pd, Nb) Thin Films

MRS Proceedings ◽

10.1557/proc-309-395 ◽

1993 ◽

Vol 309 ◽

Cited By ~ 3

Author(s):

J.D. Mis ◽

K.P. Rodbell

Keyword(s):

Thin Films ◽

Grain Size ◽

Grain Growth ◽

Weight Percent ◽

Size Distributions ◽

Precipitate Morphology ◽

X Ray ◽

Transmission Electron ◽

Grain Size Distributions

AbstractThe microstructure of 1 μim thick Al films containing 0.5 and 2%Cu (weight percent), 0.3%Pd, and 0.3%Pd-0.3%Nb were investigated by transmission electron microscopy (TEM) and energy dispersive x-ray spectroscopy (EDS) as a function of isochronal and isothermal anneals. The grain size, grain size distribution, and precipitate morphology of these films was measured from 200 to 500ºC, with the activation energy for grain growth (Ea) determined for I h anneals at 200, 300, 400 and 500ºC. Normal grain growth was recorded for the A1Cu films annealed at temperatures ≤400ºC; however secondary grain growth occurred in the AI-2Cu film annealed for I h at 500ºC, with grains as large as 16 μm in diameter observed. Grain growth in the AI-0.3Pd films resulted in strongly bi-modal grain size distributions, with the onset ofsignificant grain growth retarded for I h anneals at temperatures ≤300ºC.The addition of Nb to the AI-0.3Pd film resulted in monomodal grain size distributions over the entire temperature range. The role of crystallographic texture on grain growth in thin films is discussed.

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Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087215 ◽

1991 ◽

Vol 49 ◽

pp. 580-581

Author(s):

L. Tang ◽

G. Thomas ◽

M. R. Khan ◽

S. L. Duan

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Magnetic Recording ◽

Magnetic Thin Films ◽

Magnetic Films ◽

Substrate Bias ◽

Epitaxial Relationship ◽

Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

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Magnetic energy distribution in polycrystalline sputtered CoCr magnetic thin films

The European Physical Journal Applied Physics ◽

10.1051/epjap:2008048 ◽

2008 ◽

Vol 42 (2) ◽

pp. 125-128

Author(s):

J. F. Al-Sharab ◽

J. E. Wittig ◽

G. Bertero ◽

T. Yamashita ◽

J. Bentley ◽

...

Keyword(s):

Thin Films ◽

Energy Distribution ◽

Magnetic Energy ◽

Magnetic Thin Films

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Orientationally Resolved Grain Size Distributions in Thin Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.273-275.237 ◽

1998 ◽

Vol 273-275 ◽

pp. 237-242 ◽

Cited By ~ 4

Author(s):

J. Greiser ◽

Peter Müllner ◽

E. Arzt

Keyword(s):

Thin Films ◽

Grain Size ◽

Size Distributions ◽

Grain Size Distributions

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Structrual Characterization and Raman Scattering of Epitaxial Aluminum Nitride Thin Films on Si(111)

MRS Proceedings ◽

10.1557/proc-242-469 ◽

1992 ◽

Vol 242 ◽

Cited By ~ 1

Author(s):

W. J. Meng ◽

T. A. Perry ◽

J. Heremans ◽

Y. T. Cheng

Keyword(s):

Thin Films ◽

Aluminum Nitride ◽

Raman Scattering ◽

High Vacuum ◽

Ultra High Vacuum ◽

X Ray Diffraction ◽

X Ray ◽

Reactive Sputter Deposition ◽

Transmission Electron ◽

Substrate Temperatures

ABSTRACTThin films of aluminum nitride were grown epitaxially on Si(111) by ultra-high-vacuum dc magnetron reactive sputter deposition. Epitaxy was achieved at substrate temperatures of 600° C or above. We report results of film characterization by x-ray diffraction, transmission electron microscopy, and Raman scattering.

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Variation of the magnetic energy barrier with the cell shape of nanostructured magnetic thin films

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/42/4/045006 ◽

2009 ◽

Vol 42 (4) ◽

pp. 045006 ◽

Cited By ~ 5

Author(s):

C W Han ◽

S H Lim

Keyword(s):

Thin Films ◽

Energy Barrier ◽

Cell Shape ◽

Magnetic Energy ◽

Magnetic Thin Films

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Lattice Defects in SrRuO3 Thin Films and Their Contribution to film Resistivity

MRS Proceedings ◽

10.1557/proc-574-113 ◽

1999 ◽

Vol 574 ◽

Author(s):

N. D. Zakharov ◽

K. M. Satyalakshmi ◽

G. Koren ◽

D. Hesse

Keyword(s):

Thin Films ◽

Electrical Resistivity ◽

Lattice Defects ◽

Cubic Phase ◽

Orthorhombic Structure ◽

Film Resistivity ◽

High Electrical Resistivity ◽

Lattice Symmetry ◽

Transmission Electron ◽

Substrate Temperatures

AbstractLattice defects present in PLD-grown, epitaxial SrRuO3 thin films on (001) SrTiO3 substrates are analyzed by high resolution transmission electron microscopy (HRTEM). Before the preparation of TEM samples, the electrical resistivity of films grown at different substrate temperatures was determined. Films grown at 775 °C exhibited a low electrical resistivity of only 200 μΩcm. They were found to be of orthorhombic structure and contained only few lattice defects. Films grown at 700 °C showed a high electrical resistivity of 1400 μΩcm. They were of cubic lattice symmetry, while films grown at temperatures above 800 °C showed resistivities between 300 and 900 μΩcm. The latter films mainly consist of an orthorhombic-cubic phase mix and involve lattice defects of high density, such as twins and antiphase boundaries (APBs). These defects are mainly located in between the islands and obviously contribute to the high film resistivity observed. For example, the APBs contain an extra single SrO layer, which is certainly insulating. Moreover, Ru vacancies are present in these films.

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Microstructural Characterization Methods for Magnetic Thin Films

MRS Proceedings ◽

10.1557/proc-562-3 ◽

1999 ◽

Vol 562 ◽

Cited By ~ 2

Author(s):

J. E. Wittig ◽

J. Bentley ◽

T. P. Nolan

Keyword(s):

Thin Films ◽

High Resolution ◽

Microstructural Characterization ◽

Magnetic Thin Films ◽

Complete Analysis ◽

Structure Property ◽

Characterization Methods ◽

Transmission Electron ◽

High Resolution Tem ◽

20 Nm

ABSTRACTMicrostructural characterization is key to determining the structure-property-processing relationships required to optimize the performance of magnetic thin films for longitudinal magnetic recording. Since the grain size of modem recording media is on the order of 10 to 20 nm, only high-resolution characterization methods such as transmission electron microscopy (TEM) can accurately describe the microstructure. Complete analysis requires a combination of conventional and high-resolution TEM imaging with analytical methods such as energy dispersivespectroscopy and energy-filtered TEM imaging. This paper provides examples from CoCr(Pt,Ta) alloys that reveal the strengths and limitations of these characterization methods as they apply to microstructural characterization of magnetic thin films.

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Microstructure and Properties of CoSi2 Thin Films on (100) Silicon by Laser Physical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-285-533 ◽

1992 ◽

Vol 285 ◽

Cited By ~ 1

Author(s):

P. Tiwari ◽

R. Chowdhury ◽

J. Narayan

Keyword(s):

Thin Films ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Room Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Microstructure And Properties ◽

Transmission Electron ◽

Substrate Temperatures ◽

Deposited Films

ABSTRACTLaser physical vapor deposition (LPVD) has been used to deposit thin CoSi2 films on (001)silicon at different substrate temperatures ranging from room temperature to 600°C. Particulate-free silicide thin films were characterized by X-ray diffraction, Rutherford backscattering, and high resolution transmission electron microscopy. We have found that films deposited at 200°C and below are amorphous; 400°C deposited films are polycrystalline whereas films deposited at 600°C are of epitaxial nature. The Effect of subsequent annealing on resistivity of room-temperature deposited thin films has been investigated. The resistivity value decreases to less than 15 μΩcm after annealing making these films suitable for microelectronics applications. The correlation between microstructure and properties of these films are discussed.

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Effect of Pt content on compositional segregation in Co-Cr-P-Pt/Cr magnetic thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167573 ◽

1996 ◽

Vol 54 ◽

pp. 1022-1023

Author(s):

J-H. Choi ◽

C. M. Sung ◽

K. H. Shin ◽

L. F. Allard

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Magnetic Thin Films ◽

Low Noise ◽

Recording Media ◽

Magnetic Recording Media ◽

Physical Separation ◽

Eds Analysis ◽

Transmission Electron ◽

Compositional Segregation

Co/Cr alloys are among the most prominent materials for ultra-high density longitudinal magnetic recording media. The recording and magnetic properties of the materials are related to their microstructure. It has been found that compositional segregation (CS) of the Co phase at the grain boundaries, and physical separation of Co/Cr phases are effective in producing low noise media due to low intergranular exchange coupling. A series of Co/Cr alloy magnetic thin films were prepared by DC sputtering and studied using high-resolution transmission electron microscopy (HRTEM) coupled with energy dispersive x-ray spectroscopy (EDS). CoxCryPzPtw/Cr alloy thin films were deposited on circumferentially textured Ni-P/Al substrate. This substrate geometry was used to get better magnetic properties without substrate bias. A Hitachi HF-2000 field emission TEM was used for imaging and to provide a 1 nm beam for high spatial resolution EDS analysis.

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