摘要
为了探究FM/AFM双层膜中的交换偏置现象,利用磁控溅射法制备Co/Co O薄膜,通过改变沉积时间获得了不同Co O层厚度的Co/Co O双层膜系。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、交变梯度磁强计(AGM)、超导量子干涉仪(SQUID)分别对样品的物相结构、表面形貌及磁性能进行分析和表征。结果表明,AFM层厚度对表面形貌有一定的影响,但表面成分不随AFM层厚度的变化而变化。所有样品的XRD谱均出现Co O(002)衍射峰,说明薄膜为晶态。不同厚度的Co/Co O双层膜样品表现出不同的矫顽力和偏置场,低温下样品的磁滞回线表现出明显的交换偏置效应,并且磁偏移量随膜层厚度增加呈现逐渐增大的趋势。当Co O厚度为62.5nm时,偏置场最大可达到420k A/m。
To research exchange bias effects in bilayer systems, Co/CoO bilayers with different thickness were fabricated by magnetron sputtering technique. The thicknesses of the bilayers was controlled by deposition time. Crystalline structure and surface morphology of the films were measured by X-ray diffraction（XRD） and scanning electron microscopy（SEM）, respectively. Both the alternating gradient magnetometer（AGM） and the superconducting quantum interference device（SQUID） were employed to characterize magnetic properties of the films at room and low temperatures. The results show that the thicknesses of CoO layer of the bilayer has impacts on the coerciyty of the samples at room temperature, significant exchange bias effect was observed at low temperature, and the exchange bias field（EBF） increases with the thickness of the CoO layer. The maximum EBF achieves 5266 Oe for sample with CoO thickness of 62.5 nm.
出处
《磁性材料及器件》
CAS
2015年第3期1-4,20,共5页
Journal of Magnetic Materials and Devices
