Title :
Application of single-crystal scandium substituted barium hexaferrite for monolithic millimeter-wavelength circulators
Author :
Shi, P. ; How, H. ; Zuo, X. ; Oliver, S.A. ; McGruer, N.E. ; Vittoria, C.
fDate :
11/1/2001 12:00:00 AM
Abstract :
Single-crystal scandium-substituted barium hexaferrite crystals have been characterized and used in the fabrication of miniature monolithic circulators on silicon-glass wafers. The single crystal has an anisotropy field of 8700 Oe, saturation magnetization of 3900 G, and ferromagnetic resonance linewidth of 100 Oe. Microstrip impedance transformers were fabricated on the surrounding glass substrate to facilitate the testing and make fabrication compatible with semiconductor processing. Through-reflect-line (TRL) was used to calibrate the insertion loss and reflection due to the exponentially tapered microstrip transformer. The insertion losses are reasonably low for both unsaturated and saturated bias magnetic field conditions. Operation of the circulator has been measured at Ka-band frequencies both above and below the ferromagnetic resonance frequency
Keywords :
MIMIC; barium compounds; ferrite circulators; ferromagnetic resonance; magnetic anisotropy; magnetic leakage; magnetisation; microstrip circuits; microstrip components; millimetre wave circulators; 3900 G; BaSc0.7Fe11.3O19; Ka-band frequencies; anisotropy field; exponentially tapered microstrip transformer; ferromagnetic resonance linewidth; insertion losses; microstrip impedance transformers; monolithic millimeter-wavelength circulators; saturated bias magnetic field conditions; saturation magnetization; through-reflect-line; unsaturated bias magnetic field conditions; Anisotropic magnetoresistance; Barium; Circulators; Crystals; Fabrication; Insertion loss; Magnetic field measurement; Magnetic resonance; Microstrip; Transformers;
Journal_Title :
Magnetics, IEEE Transactions on
