Microstructural, Magnetic and Microwave Properties of Large Area BaFe$_{12}$O$_{19}$ Thick Films ($>\!100\ \mu$m) Deposited on /a-SiO$_{2}$ /Si and /a-Al$_{2}$ O$_{3}$ /Si Substrates

We have demonstrated the feasibility of thick BaFe
₁₂
O
₁₉
ceramic films fabricated on silicon (100) substrates. We obtained large area (1-in diameter) thick films (100-200 mum) by using a screen printing technique and amorphous SiO
₂
or Al
₂
O
₃
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
₂
O
₃
is superior to a-SiO
₂
as a buffer layer in achieving a tradeoff between magnetic and mechanical properties.