Cu掺杂对ZnO基薄膜光学及磁学性能影响

本文采用脉冲激光沉积(PLD)方法在单晶Si(100)衬底上沿c轴方向生长出单晶ZnCoAlO薄膜,并通过加镀Cu层调节薄膜的光学和磁学特性.采用X射线衍射仪(XRD),光致发光光谱仪,振动样品磁强计(VSM)和霍尔效应仪对薄膜的结构、光学和磁学性能进行了研究.实验表明,样品均具有纤锌矿结构并沿(002)面择优生长.加镀Cu层之后,薄膜紫外发光得到增强,掺杂导致薄膜ZnO晶格能带间隙变宽,并使得近带边激子发光增强.同时发现,在室温下Cu离子对薄膜磁性和电子浓度产生影响,Cu掺杂可以改变薄膜中载流子浓度,并影响原有磁性的双交换机理.

Optical and Magnetic Properties of Cu Doped ZnO-based Thin Films

Cu-doped ZnCoAlO films deposited on single-crystal Si(100) substrates were prepared by pulsed laser deposition(PLD).The microstructures of the ZCAO films with different Cu concentrations were characterized by X-ray diffraction(XRD),the optical and magnetic properties were measured by fluorescence spectrometer and vibrating sample magnetometer(VSM).The results show that the film has good crystallization quality,with a(002) preferential orientation.The PL spectra show that films have good UV luminescence.It was considered that the energy band gaps of the samples widen with doping compared with the ZnO films.The Cu ions occupying adjacent cation positions break the magnetic exchange interaction,which leads to the weakening of magnetic properties.