溅射法制备Mn-Zn铁氧体薄膜的磁性与微结构

以交替真空溅射的方法使用成分分别为MnFe2O4与ZnFe2O4的双靶制备了成分变化的系列Mn1-xZnxFe2O4铁氧体薄膜,衬底为Si(100)。薄膜的成分通过控制不同靶的溅射时间来进行调整。沉积态的薄膜呈非晶结构,在真空炉中以适当的温度对薄膜进行退火之后能够得到多晶Mn-Zn铁氧体薄膜。组成成分为Mn0.5Zn0.5Fe2O4的薄膜呈现了相对最高的饱和磁化强度。同时还研究了制备条件对薄膜结构与磁性的影响,如溅射氧分压,退火真空度,退火温度及薄膜厚度等等。制备的薄膜相对于块状材料具有较高的矫顽力,进而讨论了应力对薄膜矫顽力的影响。

Structure and magnetic properties of Mn-Zn ferrite films by alternative sputtering

Mn1-xZnxFe2O4 ferrite films were prepared by alternatively sputtering from two targets with the composition of MnFe2O4 and ZnFe2O4 respectively.The films were deposited on Si(100)substrates and the compositions of the film are modulated by controlling the ratio of the sputtering time from each target.The as-deposited films are amorphous.After being annealed in vacuum furnace at suitable annealing temperature,the polycrystalline Mn-Zn ferrite films were obtained.The films with composition of Mn0.5 ZnO.5Fe2O4 show a maximum saturation magnetization Ms,the effects of fabrication conditions on the film structure and magnetic properties were investigated,such as the sputtering oxygen partial pressure,annealing vacuum pressure and temperature,the thickness of the film and etc.The films show higher coercivity than that of bulk materials.the influence of stress on film(s)coercivity was discussed.