Characterization Of Magnetic Thin Films Research Articles

Experimental Techniques for the Characterization of Magnetic Thin Films

This review article describes the various experimental techniques, which are required for the characterization of magnetic thin films. Characterization is an essential process to understand the properties of magnetic thin films. By knowing the properties of these materials, one can utilize them in various technological applications as per requirements. There are different characterization tools to study the different properties of nanostructured materials. Some important experimental techniques employed to characterize the magnetic thin films are: X-Ray Diffraction, X-Ray reflectivity, Field emission scanning electron microscopy, Energy dispersive spectrometer, Transmission electron microscopy, Superconducting quantum interference device, Raman spectroscopy and X-ray absorption spectroscopy etc. These techniques will develop a better understanding of the structural, morphological, and magnetic properties of the materials to the scientific community. The discussion made in the present review article would be extremely helpful to the researchers who are doing research in the various branches of science and engineering.

Characterization of Magnetic Thin Films and Spintronic Devices Using Magneto-optic Kerr Microscopy

The magneto-optical Kerr microscopy, which allows to observe the magnetic domain structure with high sensitivity, relatively high resolution, and high dynamic performance, is becoming a basic instrument to study the properties of magnetic materials or spintronic devices. Thanks to advantages such as configuration flexibility and high compatibility with magnetic fields, electric tests, and cryogenics, a series of typical experimental research based on magneto-optical Kerr microscopy has been developed to study problems mainly involving magnetic domain morphology and dynamics. This review summarizes some classical experimental methods based on Kerr microscopy developed in recent years and their applications on material studies or spintronics device development, including the qualitative and quantitative study of defects in magnetic material, the measurement of magnetic parameters including saturation magnetization, the Heisenberg exchange stiffness, and Dzyaloshinskii–Moriya interactions, the analysis of the spin-transfer torque, or spin–orbit torque-induced magnetic dynamic in spintronic devices.

Granular Hall Sensors for Scanning Probe Microscopy.

Scanning Hall probe microscopy is attractive for minimally invasive characterization of magnetic thin films and nanostructures by measurement of the emanating magnetic stray field. Established sensor probes operating at room temperature employ highly miniaturized spin-valve elements or semimetals, such as Bi. As the sensor layer structures are fabricated by patterning of planar thin films, their adaption to custom-made sensor probe geometries is highly challenging or impossible. Here we show how nanogranular ferromagnetic Hall devices fabricated by the direct-write method of focused electron beam induced deposition (FEBID) can be tailor-made for any given probe geometry. Furthermore, we demonstrate how the magnetic stray field sensitivity can be optimized in situ directly after direct-write nanofabrication of the sensor element. First proof-of-principle results on the use of this novel scanning Hall sensor are shown.

Temperature dependence of dynamical permeability characterization of magnetic thin films using shorted microstrip line probe

A temperature dependence microwave permeability characterization system of magnetic thin film up to 10 GHz is designed and fabricated. This system can be used at temperatures ranging from room temperature to 200 °C, and is based on a shorted microstrip probe, which is made by microwave printed circuit board. Without contacting the magnetic thin films to the probe, the microwave permeability of the film can be detected without any limitations of sample size and with almost the same accuracy, as shown by comparison with the results obtained from a shorted microstrip transmission-line fixture. The complex permeability can be deduced by an analytical approach from the measured reflection coefficient of a strip line (S11) with and without a ferromagnetic film material on it. The procedures are the same with the shorted microstrip transmission-line method. The microwave permeability of an oblique deposited CoZr thin film was investigated with this probe. The results show that the room temperature dynamic permeability of the CoZr film is in good agreement with the results obtained from the established short-circuited microstrip perturbation method. The temperature dependence permeability results fit well with the Landau–Lifshitz–Gilbert equation. Development of the temperature-dependent measurement of the magnetic properties of magnetic thin film may be useful for the high-frequency application of magnetic devices at high temperatures.

Secondary resonance magnetic force microscopy using an external magnetic field for characterization of magnetic thin films

A bimodal magnetic force microscopy (MFM) that uses an external magnetic field for the detection and imaging of magnetic thin films is developed. By applying the external modulation magnetic field, the vibration of a cantilever probe is excited by its magnetic tip at its higher eigenmode. Using magnetic nanoparticle samples, the capacity of the technique which allows single-pass imaging of topography and magnetic forces is demonstrated. For the detection of magnetic properties of thin film materials, its signal-to-noise ratio and sensitivity are demonstrated to be superior to conventional MFM in lift mode. The secondary resonance MFM technique provides a promising tool for the characterization of nanoscale magnetic properties of various materials, especially of magnetic thin films with weak magnetism.

Broadband complex permeability characterization of magnetic thin films using shorted microstrip transmission-line perturbation

A brief review of the methods used for broadband complex permeability measurement of magnetic thin films up to microwave frequencies is given. In particular, the working principles of the transmission-line perturbation methods for the characterization of magnetic thin films are discussed, with emphasis on short-circuited planar transmission-line perturbation methods. The algorithms for calculating the complex permeability of magnetic thin films for short-circuited planar transmission-line perturbation methods are analyzed. A shorted microstrip line is designed and fabricated as a prototype measurement fixture. The structure of the microstrip fixture and the corresponding measurement procedure are discussed in detail. A piece of 340 nm thick FeTaN thin film deposited on Si substrate using sputtering method is characterized using the microstrip fixture. An improved technique for obtaining permeability by using a saturation magnetization field is demonstrated here, and the results fit well with the Landau–Lifchitz–Gilbert theory. Approaches to extending this method to other aspects in the investigation of magnetic thin film are also discussed.

Microwave characterization of magnetic thin films

An issue of current research is the integration of microwave ferrite devices with semiconductor technologies by using vacuum deposition techniques. Thin magnetic films may be used in commercial products and they can be more easily involved in the development of magnetic devices if we are able to extract their magnetic properties. One of the interesting points of this paper is to highlight the properties of a thin film, such as anisotropic behavior to release non reciprocal devices. A study of physicochemical and magnetic properties is tackled and experimental results are discussed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Hrem Characterization of Magnetic Thin Films and Multilayers

Journal Article Hrem Characterization of Magnetic Thin Films and Multilayers Get access David J Smith David J Smith Center for Solid State Science and Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287 Search for other works by this author on: Oxford Academic Google Scholar Microscopy and Microanalysis, Volume 8, Issue S02, 1 August 2002, Pages 382–383, https://doi.org/10.1017/S1431927602100675 Published: 01 August 2002

Surface magnetisation sensor for characterization of magnetic thin films and spin-valves structures

In this paper we present a simple model that allow us to estimate the stray magnetic field configuration near to the film surface and then a new method to perform quantitative measurements of the in plane component of the stray field, H S. For magnetic measurements we used a sensor named magnetodiode which has a very high sensitivity for magnetic fields applied in the plane of it. Are presented the results of calculations and the measurements made on thin magnetic films.

Microstructural Characterization Methods for Magnetic Thin Films

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.

ChemInform Abstract: Processing and Characterization of Magnetic Thin Films for Longitudinal Recording Media

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Magnetic thin films of cobalt nanocrystals encapsulated in graphite-like carbon

A VARIETY of crystalline materials have now been encapsulated in nanometre-scale graphitic cages1–8 and tubules9–11. For magnetic materials, encapsulation should serve the dual role of protecting air-sensitive particles against degradation and reducing the magnetic coupling between individual particles, thus potentially opening the way for applications of these composite materials as ultra-high-density magnetic recording media12,13. But to realize this potential, the materials must be available in the form of thin, smooth films, with precise control of the size of the individual magnetic crystallites. Here we report the fabrication and characterization of magnetic thin films, consisting of cobalt nanocrystals encapsulated in graphite-like carbon cages, that meet these structural requirements.