Development of a Highly Densified Magnetic Sheet for Inductors and Advanced Processes through Silane Surface Treatment of Fe Nanopowder

For developing subminiature and highly integrated multilayer inductors, soft magnetic powder was used; however, its ferrite magnetic component is characterized by high resistivity and reduced direct current saturation, leading to the deterioration of the inductor under high currents. Therefore, herein, to improve the electromagnetic properties of thin-film inductors, Fe nanopowder was used to increase the volume fraction of magnetic sheets. Surface treatment was performed by using silane coupling agents, which improved the bonding strength and dispersibility of the Fe nanopowder with a heterogeneous epoxy binder. For uniform surface treatment on the nanopowder, the silane-treated powder was aged for 24 h, at a temperature of 3 °C. The surface-treated Fe nanopowder was used with a mixing ratio of the soft magnetic powder (coarse:fine:nano) of 7:2.5:0.5 wt.%; this was successful in producing a flexible and highly densified magnetic sheet. As a result, the volume fraction of the magnetic sheet for thin-film inductors to which a low-temperature aging-treated nanopowder was applied was significantly improved.

Download Full-text

Microstructure and Electromagnetic Properties of Y3+ Substituted Mg-Mn Nanocrystalline Ferrites Via Hydrothermal Procedure

NANO ◽

10.1142/s1793292019500218 ◽

2019 ◽

Vol 14 (02) ◽

pp. 1950021

Author(s):

Renxin Xu ◽

Huan Yang ◽

Huajun Sun ◽

Jing Zhou ◽

Zhijun Yue ◽

...

Keyword(s):

Saturation Magnetization ◽

Spinel Phase ◽

Magnetic Loss ◽

Soft Magnetic Materials ◽

Electromagnetic Properties ◽

High Resistivity ◽

Soft Magnetic ◽

Hydrothermal Technique ◽

Ferrite Composites ◽

Average Size

Mg[Formula: see text]Mn[Formula: see text]YxFe[Formula: see text]O4 ([Formula: see text], 0.025, 0.050 and 0.075) nanocrystalline is synthesized via hydrothermal technique. Single cubic spinel phase is confirmed by XRD and the formation of Mg[Formula: see text]Mn[Formula: see text]YxFe[Formula: see text]O4 is verified by EDS. The average size of the nanoferrites is around 80 nm, which is examined by TEM image. Y[Formula: see text] substituted Mg-Mn nanoferrites exhibit low saturation magnetization ([Formula: see text] and coercivity ([Formula: see text]. Especially, the nanoferrites with [Formula: see text] show the lowest [Formula: see text] and [Formula: see text] of 46.96[Formula: see text]emu/g and 12.04[Formula: see text]Oe, respectively. The ferrite composites present that the resistivity and the magnetic loss are less than [Formula: see text] and 0.7 in the range of 2–18[Formula: see text]GHz, respectively. The low coercivity and high resistivity indicate that the addition of Y[Formula: see text] contributes to the synthesis of the excellent soft magnetic materials.

Download Full-text

The relaxation of compressive biaxial strains in SOS via microtwins

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155013 ◽

1989 ◽

Vol 47 ◽

pp. 608-609

Author(s):

M. E. Twigg ◽

E. D. Richmond ◽

J. G. Pellegrino

Keyword(s):

Thin Film ◽

Chemical Vapor Deposition ◽

Molecular Beam Epitaxy ◽

Compressive Stress ◽

Vapor Deposition ◽

Partial Dislocation ◽

Molecular Beam ◽

Volume Fraction ◽

Chemical Vapor ◽

Silicon Thin Film

For heteroepitaxial systems, such as silicon on sapphire (SOS), microtwins occur in significant numbers and are thought to contribute to strain relief in the silicon thin film. The size of this contribution can be assessed from TEM measurements, of the differential volume fraction of microtwins, dV/dν (the derivative of the microtwin volume V with respect to the film volume ν), for SOS grown by both chemical vapor deposition (CVD) and molecular beam epitaxy (MBE).In a (001) silicon thin film subjected to compressive stress along the [100] axis , this stress can be relieved by four twinning systems: a/6[211]/( lll), a/6(21l]/(l1l), a/6[21l] /( l1l), and a/6(2ll)/(1ll).3 For the a/6[211]/(1ll) system, the glide of a single a/6[2ll] twinning partial dislocation draws the two halves of the crystal, separated by the microtwin, closer together by a/3.

Download Full-text