Magnetic field alignment of barium ferrite thick films for microwave circulator applications

摘要

Barium ferrite films were prepared using screen printing method for their applications in self-biased microwave integrated circulators. The influences of alignment magnetic field on the microstructure and magnetic properties of the barium ferrite thick films were investigated. The results show that the (00l) peaks of the barium ferrite films are enhanced with the increase of alignment magnetic field. Hexagonal BaFe_(12)O_(19) platelets rotate and orient with c-axis perpendicular to the film plane after the magnetic field aligning. The remanence ratio of the barium ferrite films is improved from 0.52 to 0.78 with the increase of alignment magnetic field from 0 to 8 kOe. By magnetic field aligning, barium ferrite thick films with the remanence ratio of 0.8 have been prepared. A prototype of microwave integrated circulator is developed with the prepared barium ferrite films.