超音波励起フェライトメッキ法によるNiZnフェライト膜の作製

抄録

Polycrystalline films of spinel Fe_3-x-yNi_xZn_yO₄ (x = 0−0.39, y = 0-0.3) were ferrite-plated from an aqueous solution (T = 75°C, pH = 6.8) of FeCl₂ + NiCl₂ + ZnCl₂ to which an oxidizing solution of NaNO₂ had been added. Low frequency (19.5 kHz, 600 W) ultrasound waves and high-frequency (1.6 MHz, 20 W) ultrasound waves were applied during plating. When the aqueous solutions were supplied intermittently, Fe₃O₄ (x = y = 0) films with a smooth surface were obtained only when low- and high-frequency ultrasound waves were applied simultaneously. On the other hand, supplying the aqueous solutions continuously facilitated formation of Fe₃O₄ films with a smooth surface during low-frequency sonication. The simultaneous sonication increased the solubility limit of Ni ions in Fe_3-x-yNi_xZn_yO₄ films to x = 0.42 from the previous limit of x = 0.35 without sonication, though at a low deposition rate (4 nm/min).