Open Access. Powered by Scholars. Published by Universities.®

Mechanical Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Mechanical Engineering

Magnetic And Microwave Properties Of Ion-Beam-Sputtered Amorphous FeₓCo₈₀₋ₓB₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria Jun 2011

Magnetic And Microwave Properties Of Ion-Beam-Sputtered Amorphous FeₓCo₈₀₋ₓB₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria

Carmine Vittoria

Magnetically soft amorphous films of FeₓCo₈₀₋ₓB₁₅Si₅ (x = 0, 6, 23, 40, 70, 80) were ion beam sputter deposited onto fused quartz for static and microwave magnetic characterization. Films ranged in thickness from 220 to 260 nm and were deposited at rates of 0.1-0.2 nm/s. Saturation magnetization, coercivity, and loop squareness values were extracted from hysteresis loops generated by a vibrating sample magnetometer. Ferromagnetic resonance measurements were taken using a 9.5-GHz cavity with the applied magnetic field both parallel and perpendicular to the plane of the film, yielding values for the g factor, anisotropy field, effective ...


Structural And Magnetic Characterization Of Amorphous Gd₂Fe₁₄B Thin Films, S. E. Bushnell, P. C. Dorsey, W. B. Nowak, C. Vittoria Jun 2011

Structural And Magnetic Characterization Of Amorphous Gd₂Fe₁₄B Thin Films, S. E. Bushnell, P. C. Dorsey, W. B. Nowak, C. Vittoria

Carmine Vittoria

Thin amorphous films of nominal composition Gd₂Fe₁₄B were fabricated on Si (100) substrates using ion‐beam sputtering for the purpose of establishing their structural and magnetic properties at room temperature. X‐ray‐diffraction scans performed on as‐deposited and annealed films revealed an amorphous structure. The as‐deposited saturation magnetization was found to be 8101 G at room temperature suggesting ferrimagnetic ordering with anti‐parallel coupling similar to other heavy rare earth‐transition metal systems. Results from in‐plane and perpendicular ferromagnetic resonance experiments conducted at 9.108 GHz showed the films to be inhomogeneous. This was evident from the ...


The Measurement Of Magnetostriction Constants Of Thin Films Using Planar Microwave Devices And Ferromagnetic Resonance, S. E. Bushnell, W. B. Nowak, S. A. Oliver, C. Vittoria Jun 2011

The Measurement Of Magnetostriction Constants Of Thin Films Using Planar Microwave Devices And Ferromagnetic Resonance, S. E. Bushnell, W. B. Nowak, S. A. Oliver, C. Vittoria

Carmine Vittoria

In this paper we introduce a new technique for measuring the saturation magnetostriction constant (λs) for isotropic polycrystalline thin films. The technique makes use of nonresonant planar microwave structures together with a novel stressing mechanism to induce a shift in the resonant field of a magnetic thin film as measured by a ferromagnetic resonance (FMR) experiment. Measurement of the shift induced by a uniaxial stress allows for determination of λs via a magnetic resonance analysis. Either a slotline device or coplanar waveguide (CPW) was used as the source of the microwave excitation field depending upon the orientation of the dc ...


Effects Of Boron Implantation In Films Of Iron-Nickel, J. Ryu, K. Castell, W. Nowak, C. Vittoria Jun 2011

Effects Of Boron Implantation In Films Of Iron-Nickel, J. Ryu, K. Castell, W. Nowak, C. Vittoria

Carmine Vittoria

We have implanted boron ions into films of Fe-Ni alloy composition. A homogeneous distribution of boron was determined from the sputter Auger analysis with a concentration of 18% and 34% for low- and high-dose implantation, respectively. The resistivity of film was increased by a factor of 2 and 4 as a result of low- and high-dose implantation, respectively. The magnetic properties of these films are studied as a function of annealing temperature by using FMR measurements. Both the uniaxial anisotropy field and FMR linewidth are dramatically decreased as a result of annealing at elevated temperatures. The changes of effective magnetization ...


Magnetic And Structural Investigation Of Heat Treated Ion Beam Sputtered Amorphous Co₇₄Fe₆B₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria, R. J. Culbertson, W. T. Elam, K. H. Kim Jun 2011

Magnetic And Structural Investigation Of Heat Treated Ion Beam Sputtered Amorphous Co₇₄Fe₆B₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria, R. J. Culbertson, W. T. Elam, K. H. Kim

Carmine Vittoria

As-deposited and annealed specimens of ion beam sputtered amorphous Co₇₄Fe₆B₁₅Si₅ thin films were examined to explore the correlation between changes in magnetic properties and atomic structure. Specimens were characterized magnetically, by traditional ac and dc techniques and structurally, via conversion-electron extended x-ray absorption fine structure analysis. Results show significant ordering of the higher order atomic shells around the transition metal ions well below the crystallization temperature. This ordering evolves into a body- centered-cubic configuration around both the Co and Fe ions. Increases in nearest neighbor peak positions in the EXAFS Fourier transforms were observed to correlate with increasing annealing temperatures ...