The influence of substrate on the magnetic properties of MnZn ferrite thin film fabricated by alternate sputtering

✍ Scribed by Wang, Lanxi ;Bai, Jianmin ;Li, Zhenghua ;Cao, Jiangwei ;Wei, Fulin ;Yang, Zheng

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 368 KB
• Volume: 205
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200723228

✦ Synopsis

Abstract

Mn~0.5~Zn~0.5~Fe~2~O~4~ film which has the highest saturation magnetization among Mn~1–x~ Zn__~x~__ Fe~2~O~4~ thin films was prepared by the alternate rf sputtering method from two targets with compositions of MnFe~2~O~4~ and ZnFe~2~O~4~, respectively. The films were deposited on single‐crystal Si(100), MgO(100) and SiO~2~/Si(100) substrates. The as‐deposited films were amorphous, and after annealing in a vacuum furnace at 550 °C, polycrystalline MnZn ferrite films with residual amorphous matrix were obtained. The coercivity of all films is low, and the film on the MgO(100) substrate shows a coercivity as low as 27 Oe. The grain size of all films is about 20 nm and is less than the ferromagnetic exchange length (160 nm), so magnetic anisotropies are averaged to lower effective values. Furthermore, the negative magnetostriction constant of crystalline MnZn ferrite and the positive magnetostriction constant of amorphous Fe‐based matrix will cancel out and may lead to a low or vanishing saturation magnetostriction constant. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)