射频磁控溅射制备Mn掺杂ZnO薄膜的结构和铁磁性能研究

Structural and ferromagnetic properties of Mn doped ZnO thin films prepared by RF magnetron sputtering

采用射频磁控溅射法制备了Mn掺杂ZnO(Zn_(1-x)Mn_xO,其中x=0,0.03,0.06)薄膜。通过X射线衍射(XRD)、拉曼光谱(Raman)、原子力显微镜(AFM)和超导量子干涉磁强计(SQUID)对薄膜结构和磁性能进行了研究。XRD和Raman研究表明,不同浓度Mn掺杂ZnO薄膜均为ZnO的六角纤锌矿结构,并沿(002)晶面择优取向,未检测到Mn以及与Mn相关的氧化物杂相。随着Mn掺杂浓度的增大,薄膜的结晶质量下降,晶粒尺寸减小。AFM研究结果与XRD和Raman结果相一致。SQUID测量表明Mn掺杂ZnO薄膜表现出室温铁磁性,Mn掺杂量x为0.03和0.06时,在1.59×10^(6)A/m磁场下的磁化强度分别为0.12和0.18 A·m^(2)/kg。随着Mn掺杂浓度的增大,磁化强度和矫顽力增大。基于XRD、Raman和AFM研究结果,可以认为Mn掺杂ZnO薄膜的铁磁性与杂相无关,属于样品的本征磁性。

Mn doped ZnO(Zn_(1-x)Mn_(x)O,x=0,0.03,0.06)thin films were prepared by RF magnetron sputtering.The structural and ferromagnetic properties of these films were characterized by X-ray diffraction(XRD),Raman spectroscopy(Raman),atomic force microscopy(AFM)and superconducting quantum interference magnetometer(SQUID).XRD and Raman results show that the Mn doped ZnO(Zn_(1-x)Mn_(x)O,x=0,0.03,0.06)thin films have a hexagonal wurtzite structure of pure ZnO with highly(002)preferential orientation.No Mn element and oxides can be detected.As the Mn dopant concentration increases,the crystalline quality and grain size of the films decrease.The AFM results are consistent with XRD and Raman.SQUID measurements show that Mn doped ZnO films exhibit room temperature ferromagnetism,and the magnetization at 1.59×10^(6)A/m magnetic field is 0.12 and 0.18 A·m^(2)/kg when the Mn dopant amount x is 0.03 and 0.06 respectively.With higher Mn dopant concentration,the magnetization and coercivity increase.According to XRD,Raman and AFM results,it can be deduced that the ferromagnetism of the Mn doped ZnO films is independent of the impurity phases and inherent to the samples.