Composition, microstructures and ferrimagnetic properties of Bi-modified LiZnTiMn ferrites for LTCC application

The effects of Bi modification on the microstructural development and gyromagnetic properties of low-temperature sintered ferrites with composition of Li0.42Zn0.27Ti0.11Mn0.1Fe2.1−xBixO4 (x = 0.0-0.1) have been studied in order to adapt the development of low-temperature cofired ceramics technology (LTCC) and produce gyromagnetic devices with a multilayer process. In the present work, a pure spinel phase can be formed with a sintering temperature ranging from 880°C to 900°C, which allows them to be co-fired with silver. We found that Bi3+ ions could enter into the ferrite lattice, which enhanced the grain growth and densification during sintering due to the activation of the lattice. Results show that the modifying of x = 0.003 cannot only double saturation induction but also drastically reduce ferromagnetic resonance line width at 9.3 GHz, indicating that Bi modification is a good approach for lowing the sintering temperature of LiZnTiMn ferrites.