Preparation of high-quality hexaferrite thick films by an improved liquid phase epitaxy deposition technique

In this paper, we report on the deposition of thick and high-quality films of BaM on (111) gadolinium gallium garnet (GGG) and m-plane, (11_00) or (101_0), sapphire (Al₂O₃) substrates. The deposition rate is sufficiently high to allow for large batch production. The total thickness ranged from 50 to 200 μm for 2 h of the liquid phase epitaxy deposition. Therefore, the growth rate of the films ranged from ∼25 to ∼100 μm/h. In previous work, growth rates in BaM films were quite small. Equally important, the ferrimagnetic resonance (FMR) linewidth (ΔH) was ∼0.068 kOe at 58 GHz for the BaM films on (111) GGG and ∼0.08 kOe at 59.9 GHz for the BaM film on m-plane sapphire substrates. The FMR linewidth films of thick BaM films deposited by pulsed laser deposition in earlier work ranged from 0.5 to 1.2 kOe.