Magnetic Field MEMS-Sensor: Functional Characteristics Control during the Formation of Magnetosensitive Structures

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.386.161 ◽

2018 ◽

Vol 386 ◽

pp. 161-166

Author(s):

Nikolay Djuzhev ◽

Aleksey Iurov ◽

Maksim Chinenkov

Keyword(s):

Magnetic Field ◽

Coercive Force ◽

Substrate Temperature ◽

Temperature Effects ◽

Functional Characteristics ◽

Magnetic Structures ◽

Mems Sensor

In this work the results of substrate temperature effects on coercivity and magnetoresistance in ferromagnetic structures are shown. It was found that with an increase of the substrate temperature from 270 to 390 °C the magnetoresistance increases from 1.2 to 2.3% and the coercive force from 1.6 to 5.3 Oe. A new topology of anisotropic magnetoresistive structures is proposed. In these structures the shape of ferromagnetic elements repeats the shape of nonmagnetic conducting shunts. Sensitivity values obtained for both types of magnetic structures are compared.

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Effects of average grain size on the magnetic properties of permalloy films

EPJ Web of Conferences ◽

10.1051/epjconf/201818501003 ◽

2018 ◽

Vol 185 ◽

pp. 01003 ◽

Cited By ~ 2

Author(s):

Nikolay Djuzhev ◽

Aleksey Iurov ◽

Nikita Mazurkin ◽

Maksim Chinenkov ◽

Aleksey Trifonov ◽

...

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Coercive Force ◽

Substrate Temperature ◽

Temperature Effects ◽

Deposition Temperature ◽

High Sensitivity ◽

Permalloy Film ◽

Average Grain Size

In this paper the results of substrate temperature effects on average grain size in FeNi 20:80 are shown. It was found that with an increase of the substrate temperature from 270 to 390 °C, the anisotropic magnetoresistive (AMR) effect increases from 1.2 to 2.3% and the coercive force from 1.6 to 5.3 Oe. The presence of two conflicting processes: the task of increasing AMR effect to achieve high sensitivity of AMR-sensor and to decrease the coercive force to increase the precision of conversion, leads to the necessity to find the optimum deposition temperature of the permalloy film. The dependence of the AMR effect and the coercive force on the substrate temperature during deposition was obtained. This dependence shows that the substrate temperature increasing above 320 °C leads to coercive force increasing and does not lead to a substantial AMR increasing. In this regard, the substrate temperature 320 °C was determined as optimal.

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Magnetic Nanodiscs—A New Promising Tool for Microsurgery of Malignant Neoplasms

Nanomaterials ◽

10.3390/nano11061459 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1459

Author(s):

Tatiana N. Zamay ◽

Vladimir S. Prokopenko ◽

Sergey S. Zamay ◽

Kirill A. Lukyanenko ◽

Olga S. Kolovskaya ◽

...

Keyword(s):

Magnetic Field ◽

Remote Control ◽

Tumor Cells ◽

Biological Effects ◽

Malignant Neoplasms ◽

Rotating Magnetic Fields ◽

Magnetic Structures ◽

Promising Tool

Magnetomechanical therapy is one of the most perspective directions in tumor microsurgery. According to the analysis of recent publications, it can be concluded that a nanoscalpel could become an instrument sufficient for cancer microsurgery. It should possess the following properties: (1) nano- or microsized; (2) affinity and specificity to the targets on tumor cells; (3) remote control. This nano- or microscalpel should include at least two components: (1) a physical nanostructure (particle, disc, plates) with the ability to transform the magnetic moment to mechanical torque; (2) a ligand—a molecule (antibody, aptamer, etc.) allowing the scalpel precisely target tumor cells. Literature analysis revealed that the most suitable nanoscalpel structures are anisotropic, magnetic micro- or nanodiscs with high-saturation magnetization and the absence of remanence, facilitating scalpel remote control via the magnetic field. Additionally, anisotropy enhances the transmigration of the discs to the tumor. To date, four types of magnetic microdiscs have been used for tumor destruction: synthetic antiferromagnetic P-SAF (perpendicular) and SAF (in-plane), vortex Py, and three-layer non-magnetic–ferromagnet–non-magnetic systems with flat quasi-dipole magnetic structures. In the current review, we discuss the biological effects of magnetic discs, the mechanisms of action, and the toxicity in alternating or rotating magnetic fields in vitro and in vivo. Based on the experimental data presented in the literature, we conclude that the targeted and remotely controlled magnetic field nanoscalpel is an effective and safe instrument for cancer therapy or theranostics.

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Thermal Relaxation of Very Small Solar Magnetic Structures in Intergranules: A Process That Produces Kilogauss Magnetic Field Strengths

The Astrophysical Journal ◽

10.1086/321532 ◽

2001 ◽

Vol 556 (2) ◽

pp. 928-936 ◽

Cited By ~ 17

Author(s):

J. Sanchez Almeida

Keyword(s):

Magnetic Field ◽

Thermal Relaxation ◽

Magnetic Structures ◽

Field Strengths

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Substrate temperature effects on the growth and properties of γ-MnS thin films grown by rf sputtering

Materials Research Bulletin ◽

10.1016/s0025-5408(02)00865-6 ◽

2002 ◽

Vol 37 (10) ◽

pp. 1749-1754 ◽

Cited By ~ 21

Author(s):

I Oidor-Juárez ◽

P Garcı́a-Jiménez ◽

G Torres-Delgado ◽

R Castanedo-Pérez ◽

O Jiménez-Sandoval ◽

...

Keyword(s):

Thin Films ◽

Substrate Temperature ◽

Temperature Effects ◽

Rf Sputtering

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Magnetic properties of cobalt microwires measured by piezoresistive cantilever magnetometry

Nanofabrication ◽

10.2478/nanofab-2014-0008 ◽

2014 ◽

Vol 1 (1) ◽

Cited By ~ 3

Author(s):

G. Tosolini ◽

J. M. Michalik ◽

R. Córdoba ◽

J. M. de Teresa ◽

F. Pérez-Murano ◽

...

Keyword(s):

Magnetic Field ◽

Room Temperature ◽

Signal To Noise Ratio ◽

Static Deflection ◽

Magnetic Structures ◽

Dual Beam ◽

Piezoresistive Cantilevers ◽

Good Signal ◽

The Magnetic Field

AbstractWe present the magnetic characterization of cobalt wires grown by focused electron beam-induced deposition (FEBID) and studied using static piezoresistive cantilever magnetometry. We have used previously developed high force sensitive submicron-thick silicon piezoresistive cantilevers. High quality polycrystalline cobalt microwires have been grown by FEBID onto the free end of the cantilevers using dual beam equipment. In the presence of an external magnetic field, the magnetic cobalt wires become magnetized, which leads to the magnetic field dependent static deflection of the cantilevers. We show that the piezoresistive signal from the cantilevers, corresponding to a maximum force of about 1 nN, can be measured as a function of the applied magnetic field with a good signal to noise ratio at room temperature. The results highlight the flexibility of the FEBID technique for the growth of magnetic structures on specific substrates, in this case piezoresistive cantilevers.

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