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Magnetic Anisotropy And Crystalline Texture In Bao(Fe₂O₃)₆ Thin Films Deposited On Gan/Al₂O₃, Paul R. Ohodnicki, K. Y. Goh, Yuranan Hanlumyuang, K. Ramos, Michael E. Mchenry, Zhuhua Cai, Katherine Ziemer, Hadis Morkoc, Necmi Biyikli, Zhaohui Chen, C. Vittoria, Vincent Girard Harris (1962-)
Magnetic Anisotropy And Crystalline Texture In Bao(Fe₂O₃)₆ Thin Films Deposited On Gan/Al₂O₃, Paul R. Ohodnicki, K. Y. Goh, Yuranan Hanlumyuang, K. Ramos, Michael E. Mchenry, Zhuhua Cai, Katherine Ziemer, Hadis Morkoc, Necmi Biyikli, Zhaohui Chen, C. Vittoria, Vincent Girard Harris (1962-)
Vincent G. Harris
BaO(Fe₂O₃)₆ (BaM) thin films were deposited by pulsed laser deposition on GaN/Al₂O₃ substrates. A pole figure obtained from the (006) reflection indicated that ~81% of the film volume had the c axis tilted less than 5° from the film normal. A low anisotropy field was inferred from vector coil vibrating sample magnetometer (VVSM) measurements. The reduction in Hₐ from literature values and a two-step switching of the easy axis magnetization is postulated to result from interdiffusion and misalignment effects. To alleviate interdiffusion and to improve the c-axis alignment, experiments were repeated with lower deposition temperatures, thinner films, and MgO buffer …
Correlation Between Texture, Anisotropy, And Vector Magnetization Processes Investigated By Two-Dimensional Vector Vibrating Sample Magnetometry In Bao(Fe₂O₃)₆ Thin Film, Paul Ohodnicki, K. Goh, Michael Mchenry, Katherine Ziemer, Zhaohui Chen, C. Vittoria, Vincent Harris (1962-)
Correlation Between Texture, Anisotropy, And Vector Magnetization Processes Investigated By Two-Dimensional Vector Vibrating Sample Magnetometry In Bao(Fe₂O₃)₆ Thin Film, Paul Ohodnicki, K. Goh, Michael Mchenry, Katherine Ziemer, Zhaohui Chen, C. Vittoria, Vincent Harris (1962-)
Vincent G. Harris
High ferromagnetic resonance frequencies and low linewidths in BaO(Fe₂O₃)₆ thin films are achieved by obtaining a low-dispersion of crystallite easy c axes normal to the film. X-ray diffraction and magnetic force microscopy are used to characterize texture and magnetic domain structure for a BaO(Fe₂O₃)₆ film deposited on (0001) SiC with a MgO (111) template layer. Strong c-axis texture normal to the film is observed resulting in strong uniaxial anisotropy. The consequent vector magnetization processes due to a combination of domain wall motion and magnetization rotation are characterized by two dimensional vector coil vibrating sample magnetometry (VVSM).
Epitaxial Growth Of M-Type Ba-Hexaferrite Films On Mgo (111) || Sic (0001) With Low Ferromagnetic Resonance Linewidths, Zhaohui Chen, Aria Fan Yang, Anton Geiler, Vincent Girard Harris (1962-), C. Vittoria, Paul R. Ohodnicki, K. Y. Goh, Michael E. Mchenry, Zhuhua Cai, Trevor L. Goodrich, Katherine S. Ziemer
Epitaxial Growth Of M-Type Ba-Hexaferrite Films On Mgo (111) || Sic (0001) With Low Ferromagnetic Resonance Linewidths, Zhaohui Chen, Aria Fan Yang, Anton Geiler, Vincent Girard Harris (1962-), C. Vittoria, Paul R. Ohodnicki, K. Y. Goh, Michael E. Mchenry, Zhuhua Cai, Trevor L. Goodrich, Katherine S. Ziemer
Vincent G. Harris
Barium hexaferrite (BaM) films were deposited on 10 nm MgO (111) films on 6H silicon carbide (0001) substrates by pulsed laser deposition from a homogeneous BaFe₁₂O₁₉ target. The MgO layer, deposited by molecular beam epitaxy, alleviated lattice mismatch and interdiffusion between film and substrate. X-ray diffraction showed strong crystallographic alignment while pole figures exhibited reflections consistent with epitaxial growth. After optimized annealing, these BaM films have a perpendicular magnetic anisotropy field of 16 900 Oe, a magnetization (as 4πs) of 4.4 kG, and a ferromagnetic resonance peak-to-peak derivative linewidth at 53 GHz of 96 Oe, thus demonstrating sufficient properties for …
Structure And Magnetism Of Ba-Hexaferrite Films Grown On Single Crystal 6-H Sic With Graduated Interfacial Mgo Buffer Layers, Zhaohui Chen, Aria Fan Yang, Zhuhua Cai, Soack Dae Yoon, Katherine S. Ziemer, C. Vittoria, Vincent Girard Harris (1962-)
Structure And Magnetism Of Ba-Hexaferrite Films Grown On Single Crystal 6-H Sic With Graduated Interfacial Mgo Buffer Layers, Zhaohui Chen, Aria Fan Yang, Zhuhua Cai, Soack Dae Yoon, Katherine S. Ziemer, C. Vittoria, Vincent Girard Harris (1962-)
Vincent G. Harris
M-type barium hexaferrite films were processed by pulsed laser deposition on single-crystal 6-H silicon carbide substrates. MgO buffer and barrier layers were introduced to improve the film quality. Samples were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, X-ray diffraction, vibrating sample magnetometry, and ferromagnetic resonance (FMR). X-ray θ − 2θ diffraction measurements indicated a strong (0, 0, 2n) crystallographic alignment. The magnetization of the BaM film is comparable to bulk values (4πMs ∼ 4320 G). A derivative power FMR linewidth of 500 Oe was measured at 55 GHz for the as-deposited films. This paper explores a …
Ba-Hexaferrite Films For Next Generation Microwave Devices, Vincent Harris (1962-), Zhaohui Chen, Yajie Chen, Soack Yoon, Tomokuza Sakai, Anton Geiler, Aria Yang, Yongxue He, Katherine Ziemer, Nian Sun, C. Vittoria
Ba-Hexaferrite Films For Next Generation Microwave Devices, Vincent Harris (1962-), Zhaohui Chen, Yajie Chen, Soack Yoon, Tomokuza Sakai, Anton Geiler, Aria Yang, Yongxue He, Katherine Ziemer, Nian Sun, C. Vittoria
Vincent G. Harris
Next generation magnetic microwave devices require ferrite films to be thick (>300 μm), self-biased (high remanent magnetization), and low loss in the microwave and millimeter wave bands. Here we examine recent advances in the processing of thick Ba-hexaferrite (M-type) films using pulsed laser deposition (PLD), liquid-phase epitaxy, and screen printing. These techniques are compared and contrasted as to their suitability for microwave materials processing and industrial production. Recent advances include the PLD growth of BaM on wide-band-gap semiconductor substrates and the development of thick, self-biased, low-loss BaM films by screen printing.