Thin-Film Permanent Magnets for Integrated Electromagnetic Components

摘要

Methods were developed under this program that allow the deposition and photo-patterning of relatively thick (up to 100 microns) high-energy product (15-25 MgOe) highly oriented films of Sm-Co based permanent magnet materials onto various substrate materials, including GaAs and sapphire. The deposition process allows the magnetization to be in any direction desired in the plane of the film. The films have a Curie point of 700 Celsius and are stable. NdFeB films, with magnetization perpendicular to the plane of the film, were also deposited. Methods developed included: Direct crystallization, in the presence of a magnetic field, of the sputtered materials onto heated substrates; the use of a Aluminum oxide boundary layer to promote adhesion and allow the growth of thick films; and the use of Ar and Xe as a sputtering gas to thermalize the sputtered atoms. Magnets such as those developed under this contract are a significant advance towards providing thin-film bias magnets for planar nonreciprocal microwave devices such as circulators and isolators. Thin-Film Magnets, Samarium Cobalt, Neodymium Iron-Boron, Sputtering, Non-Reciprocal Devices, Magnets.