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Oriented Barium Hexaferrite Thick Films With Narrow Ferromagnetic Resonance Linewidth, Y. J. Chen, T. Sakai, T. Y. Chen, S. D. Yoon, A. L. Geiler, C. Vittoria, V. G. Harris
Oriented Barium Hexaferrite Thick Films With Narrow Ferromagnetic Resonance Linewidth, Y. J. Chen, T. Sakai, T. Y. Chen, S. D. Yoon, A. L. Geiler, C. Vittoria, V. G. Harris
Vincent G. Harris
Hexagonal BaFe₁₂O₁₉ ferrite films, having thicknesses ranging from 200-500μm, were prepared by a screen printing process followed by sintering heat treatments. Structural, magnetic, and microwave measurements confirmed that the polycrystalline films were suitable for applications in self-biasing microwave devices in that they exhibited a large remanence (4πMr=3800 G), high hysteresis loop squareness (Mr/Ms=0.96) and low microwave loss. A derivative linewidth ΔH of 310 Oe was measured at 55.6 GHz. This represents the lowest ΔH measured in polycrystalline hexaferrite materials. ΔH can be further improved by reducing porosity and improving the c-axis orientation of grains in polycrystalline ferrite.
Alternating Target Laser Ablation Deposition Of High Quality Barium Hexaferrite Thin Films From Barium Monoferrite And Hematite Targets, A. L. Geiler, S. D. Yoon, Y. Chen, A. Yang, C. N. Chinnasamy, M. Geiler, V. G. Harris, C. Vittoria
Alternating Target Laser Ablation Deposition Of High Quality Barium Hexaferrite Thin Films From Barium Monoferrite And Hematite Targets, A. L. Geiler, S. D. Yoon, Y. Chen, A. Yang, C. N. Chinnasamy, M. Geiler, V. G. Harris, C. Vittoria
Vincent G. Harris
An optimized alternating target laser ablation deposition (ATLAD) technique has been developed to grow high quality barium hexaferrite (BaFe₁₂O₁₉) thin films on basal plane oriented sapphire(Al₂O₃) substrates from barium monoferrite (BaFe₂O₄) and hematite (α-Fe₂O₃) targets. Crystallographic and structural characterization results show that the films possess low c-axis dispersion of Δ ω=0.259 degrees and hexagonal terraced surface morphology. Saturation magnetization and uniaxial magnetic anisotropy field were determined to be consistent with reference data on high quality barium hexaferrite films and bulk single crystals grown by other techniques. Ferromagnetic resonance linewidth of 42 Oe was measured at 52 GHz by the shorted …
Bafe₁₂O₁₉ Thin Films Grown At The Atomic Scale From Bafe₂O₄ And Α-Fe₂O₃ Targets, A. L. Geiler, S. D. Yoon, Y. Chen, C. N. Chinnasamy, Z. Chen, M. Geiler, V. G. Harris, C. Vittoria
Bafe₁₂O₁₉ Thin Films Grown At The Atomic Scale From Bafe₂O₄ And Α-Fe₂O₃ Targets, A. L. Geiler, S. D. Yoon, Y. Chen, C. N. Chinnasamy, Z. Chen, M. Geiler, V. G. Harris, C. Vittoria
Vincent G. Harris
Hexagonal barium ferrite (BaFe₁₂O₁₉) thin films were grown at the atomic scale by alternating target laser ablation deposition (ATLAD) of orthorhombic BaFe₂O₄ and rhombohedral α-Fe₂O₃ on < 001 > Al₂O₃ substrates. Crystallographic, magnetic, and microwave properties of the ATLAD films were determined to be comparable with single crystal quality bulk and films of BaFe₁₂O₁₉ produced by other techniques. The ability to deposit high quality hexagonal ferrite thin films by utilizing multiple targets of different chemical compositions in the deposition routine provides unique opportunities to control the ionic distribution in the unit cell of this important class of ferrite materials.
Alternating Target Laser Ablation Deposition Of High Quality Barium Hexaferrite Thin Films From Barium Monoferrite And Hematite Targets, A. L. Geiler, S. D. Yoon, Y. Chen, A. Yang, C. N. Chinnasamy, M. Geiler, V. G. Harris, C. Vittoria
Alternating Target Laser Ablation Deposition Of High Quality Barium Hexaferrite Thin Films From Barium Monoferrite And Hematite Targets, A. L. Geiler, S. D. Yoon, Y. Chen, A. Yang, C. N. Chinnasamy, M. Geiler, V. G. Harris, C. Vittoria
Carmine Vittoria
An optimized alternating target laser ablation deposition (ATLAD) technique has been developed to grow high quality barium hexaferrite (BaFe₁₂O₁₉) thin films on basal plane oriented sapphire(Al₂O₃) substrates from barium monoferrite (BaFe₂O₄) and hematite (α-Fe₂O₃) targets. Crystallographic and structural characterization results show that the films possess low c-axis dispersion of Δ ω=0.259 degrees and hexagonal terraced surface morphology. Saturation magnetization and uniaxial magnetic anisotropy field were determined to be consistent with reference data on high quality barium hexaferrite films and bulk single crystals grown by other techniques. Ferromagnetic resonance linewidth of 42 Oe was measured at 52 GHz by the shorted …
Magnetic And Microwave Magnetic Properties Of Barium Hexaferrite Permanent Magnet Films Having The C-Axis In The Film Plane, S. D. Yoon, C. Vittoria, S. A. Oliver
Magnetic And Microwave Magnetic Properties Of Barium Hexaferrite Permanent Magnet Films Having The C-Axis In The Film Plane, S. D. Yoon, C. Vittoria, S. A. Oliver
Carmine Vittoria
Thick (1-14 μm) films of ferrimagnetic barium hexaferrite (BaFe₁₂O₁₉ or BaM) having the c-axis ([0001]) in the film plane were deposited by pulsed laser deposition onto a-plane (1120) sapphire (Al₂O₃) substrates, and were found to have a (1010) orientation. Torque and magnetization measurements show these films are permanent magnets with easy magnetization direction in the plane of the film. Ferrimagnetic resonance (FMR) spectra exhibited linewidths of 1.00-1.40 kOe, where low-field FMR measurements do not show uniform mode broadening due to the formation of multiple domains. All film parameters were affected by the large stress present in these films due to …
Bafe₁₂O₁₉ Thin Films Grown At The Atomic Scale From Bafe₂O₄ And Α-Fe₂O₃ Targets, A. L. Geiler, S. D. Yoon, Y. Chen, C. N. Chinnasamy, Z. Chen, M. Geiler, V. G. Harris, C. Vittoria
Bafe₁₂O₁₉ Thin Films Grown At The Atomic Scale From Bafe₂O₄ And Α-Fe₂O₃ Targets, A. L. Geiler, S. D. Yoon, Y. Chen, C. N. Chinnasamy, Z. Chen, M. Geiler, V. G. Harris, C. Vittoria
Carmine Vittoria
Hexagonal barium ferrite (BaFe₁₂O₁₉) thin films were grown at the atomic scale by alternating target laser ablation deposition (ATLAD) of orthorhombic BaFe₂O₄ and rhombohedral α-Fe₂O₃ on < 001 > Al₂O₃ substrates. Crystallographic, magnetic, and microwave properties of the ATLAD films were determined to be comparable with single crystal quality bulk and films of BaFe₁₂O₁₉ produced by other techniques. The ability to deposit high quality hexagonal ferrite thin films by utilizing multiple targets of different chemical compositions in the deposition routine provides unique opportunities to control the ionic distribution in the unit cell of this important class of ferrite materials.
Microwave And Magnetic Properties Of Self-Biased Barium Hexaferrite Screen Printed Thick Films, Y. J. Chen, A. L. Geiler, T. Sakai, S. D. Yoon, C. Vittoria, V. G. Harris
Microwave And Magnetic Properties Of Self-Biased Barium Hexaferrite Screen Printed Thick Films, Y. J. Chen, A. L. Geiler, T. Sakai, S. D. Yoon, C. Vittoria, V. G. Harris
Vincent G. Harris
The interest in barium hexaferrite thick films, particularly with high remanent magnetization, is driven by the development of small planar ferrite microwave devices. We report here processing and microwave characterization of BaFe₁₂O₁₉ ferrite thick films (100-400 μm). The films were deposited on silicon and alumina substrates by screen printing, oriented under a magnetic field of 8 kOe, then annealed at 250°C and sintered at temperatures ranging from 850 to 1300°C. Scanning electron microscopy and x-ray diffraction exhibited strong crystallographic alignment of c-axis crystals perpendicular to the film plane. The magnetization measurement indicated that a typical dense film with 270 μm …
Microwave And Magnetic Properties Of Double-Sided Hexaferrite Films On (111) Magnesium Oxide Substrates, S. G. Wang, S. D. Yoon, C. Vittoria
Microwave And Magnetic Properties Of Double-Sided Hexaferrite Films On (111) Magnesium Oxide Substrates, S. G. Wang, S. D. Yoon, C. Vittoria
Carmine Vittoria
We have deposited hexaferrite films of BaFe₁₂O₁₉ on both sides of a magnesium oxide, (111) MgO, substrate by the liquid phase epitaxy (LPE) deposition technique. The procedure entailed the deposition of seed layers of BaFe₁₂O₁₉ onto the substrate by laser ablation deposition and then dipping of the substrate into a molten flux. Whereas the seed layers were the order of 0.5 μm, the total thickness after LPE deposition was ∽45 μm. The ferrimagnetic resonance linewidth at 60 GHz, 27 Oe, is as low as it has ever been measured before in BaFe₁₂O₁₉ to the best of our knowledge. The static …
Enhanced Coercive And Remanence Fields For Cofe₂O₄ And Bafe₁₂O₁₉ Bilayers Deposited On (111) Mgo, S. D. Yoon, S. A. Oliver, C. Vittoria
Enhanced Coercive And Remanence Fields For Cofe₂O₄ And Bafe₁₂O₁₉ Bilayers Deposited On (111) Mgo, S. D. Yoon, S. A. Oliver, C. Vittoria
Carmine Vittoria
High quality epitaxial bilayer films of spinel CoFe₂O₄ (CoF) and M-type hexagonal ferrite BaFe₁₂O₁₉ (BaM) were deposited onto (111) magnesium oxide (MgO) substrate by pulsed laser ablation deposition. X-ray diffraction patterns of both BaM/CoF and CoF/BaM films showed only (0001) BaM, (111) CoF, and (111) MgO peaks. The highest coercive field of Hc=1.4 kOe was obtained for a BaM/CoF film where the CoF layer was deposited at 400°C, which was higher than typical Hc values of ∽0.4 kOe found for single layer BaM films on (111) MgO. This was less than the Hc ∽3.0 kOe found for (111) CoF films …
Microwave And Magnetic Properties Of Barium Hexaferrite Films Having The C-Axis In The Film Plane By Liquid Phase Epitaxy Technique, S. D. Yoon, C. Vittoria
Microwave And Magnetic Properties Of Barium Hexaferrite Films Having The C-Axis In The Film Plane By Liquid Phase Epitaxy Technique, S. D. Yoon, C. Vittoria
Carmine Vittoria
We report the growth of thick barium hexaferrite (BaFe₁₂O₁₉,BaM) films on m-planes ([1100] or [1010]) sapphire (Al₂O₃) substrates by the liquid phase epitaxy deposition technique. The procedure entailed the deposition of seed layers of BaFe₁₂O₁₉ onto the substrate by the pulsed laser ablation deposition and then dipping the substrate into a molten flux for 2 h. The total thickness ranged from 60 μm to 200 μm. The vibrating sample magnetometer (VSM) measurement data showed that the film exhibited magnetic uniaxial anisotropy axis in the film plane. The coercive field was relatively small, range of Hc was from 0.007 kOe to …
Pulsed Laser Deposition Of Epitaxial Bafe₁₂O₁₉ Thin-Films, C. A. Carosella, D. B. Chrisey, P. Lubitz, J. S. Horwitz, P. Dorsey, R. Seed, C. Vittoria
Pulsed Laser Deposition Of Epitaxial Bafe₁₂O₁₉ Thin-Films, C. A. Carosella, D. B. Chrisey, P. Lubitz, J. S. Horwitz, P. Dorsey, R. Seed, C. Vittoria
Carmine Vittoria
Epitaxial thin films of barium hexaferrite (BaFe₁₂O₁₉) have been fabricated by the pulsed laser deposition technique on basal plane sapphire. Structural studies reveal the films to be predominantly single phase and crystalline, with the c axis oriented perpendicular to the film plane. The magnetic parameters deduced from vibrating sample magnetometer and ferromagnetic resonance (FMR) measurements are close to the parameters associated with bulk materials. Post annealing of the films reduced the FMR linewidth by more than a factor of 3 so that it compares reasonably well with single-crystal films. The derivative FMR linewidth was measured to be 66 Oe at …
Microwave And Magnetic Properties Of Self-Biased Barium Hexaferrite Screen Printed Thick Films, Y. J. Chen, A. L. Geiler, T. Sakai, S. D. Yoon, C. Vittoria, V. G. Harris
Microwave And Magnetic Properties Of Self-Biased Barium Hexaferrite Screen Printed Thick Films, Y. J. Chen, A. L. Geiler, T. Sakai, S. D. Yoon, C. Vittoria, V. G. Harris
Carmine Vittoria
The interest in barium hexaferrite thick films, particularly with high remanent magnetization, is driven by the development of small planar ferrite microwave devices. We report here processing and microwave characterization of BaFe₁₂O₁₉ ferrite thick films (100-400 μm). The films were deposited on silicon and alumina substrates by screen printing, oriented under a magnetic field of 8 kOe, then annealed at 250°C and sintered at temperatures ranging from 850 to 1300°C. Scanning electron microscopy and x-ray diffraction exhibited strong crystallographic alignment of c-axis crystals perpendicular to the film plane. The magnetization measurement indicated that a typical dense film with 270 μm …
Thick M-Type Barium Hexaferrite Films Grown On Garnet Substrates, C. Vittoria, S. D. Chen
Thick M-Type Barium Hexaferrite Films Grown On Garnet Substrates, C. Vittoria, S. D. Chen
Carmine Vittoria
The deposition and characterization of thick M-type barium hexaferrite (BaFe₁₂O₁₉) films produced by a modified liquid phase epitaxy deposition technique are reported. The films are deposited on (111) oriented single crystal garnet (Gd₃Ga₅O₁₂) substrates. The thickness of the films ranged between 45 and 80 μm with growth rates of up to 40 μm/h. This growth rate is about five times greater than films grown on substrates of (111) magnesium oxide. Although the films are relatively thick, the ferrimagnetic resonance linewidth is remarkably narrow.