Microstructural, Magnetic and Microwave Properties of Large Area BaFe O Thick Films ( m) Deposited on /a-SiO /Si and /a-Al O /Si Substrates

We have demonstrated the feasibility of thick BaFe O ceramic films fabricated on silicon (100) substrates. We obtained large area (1-in diameter) thick films (100‐200 m) by using a screen printing technique and amorphous SiO or Al O buffer layers. To characterize the microstructural, magnetic, and microwave properties of ferrite films, we employed X-ray diffractometry, scanning electron microscopy, energy dispersive X-ray spectroscopy, dc magnetometry, and ferromagnetic resonance (FMR). We placed our emphasis on investigating silicon diffusion in terms of a depth analysis of composition for different buffer layers. We present and discuss FMR measurements for two polycrystalline samples with different buffer layers. We find that a-Al O is superior to a-SiO as a buffer layer in achieving a tradeoff between magnetic and mechanical properties. Index Terms—Hexaferrite, microwave, screen printing, silicon.