Magnetodielectric Bi–Co–Ti substituted M-type hexaferrite with high and matching permeability and permittivity in very high frequency

Low loss and high refractive index in impedance-matched ferrite–silver co-fired ceramics

“…4 shows the refractive index and impedance of the co-fired ceramics. On one hand, all samples have high refractive index of 23.2-26.8, which are much higher than previous reports [6][7][8][9][10][11][12][13][14][15][16][17][18][19]. It indicates that if they are used as the substrate material the physical dimension of HF antennas can be remarkably reduced by a factor of $25.…”

“…High refractive index of substrate materials can reduce the antenna size by a factor of n [2,3], while the impedance matching can alleviate the interface reflectance and reduce the energy trapped in substrate [4]. Great efforts have been paid on singlephased materials [5][6][7][8][9][10][11][12] and composite materials [13] to produce equal permeability and permittivity. For example, Su et al obtained the equal permeability and permittivity of 12 in NiZnCu ferrite [5].…”

Magnetic and electrical properties of Z-type hexaferrites sintered in different atmospheres

“…Recently, with the development of wireless systems, hexaferrites have received renewed attention for their potential applications as low-loss antenna substrate materials [1][2][3][4][5][6][7][8][9][10].…”

Engineering soft magnetic properties by doping ions in low-fired M-type hexaferrite with Bi–Co–Ti substitution

“…[13][14][15] The authors' previous work reported the properties of a Bi-Co-Ti substituted M-type hexaferrite (Ba 1Àx Bi x (Co 1.1+x Ti 1.1 ) Fe 9.8Àx O 19 ). 21,22 The Bi-Co-Ti substitution remarkably lowers the high sintering temperature of M-type hexaferrite to below 1000 C, so it meets the need of low temperature co-red ceramics (LTCC) technology and can be used to fabricate multilayer chip devices. Moreover, the low heat-treatment temperature controls the valence variation of transition metal ions, which enhances the magnetic properties, such as a higher permeability than that of a Co-Ti substituted M-type hexaferrite.…”