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采用脉冲激光沉积(PLD)方法在单晶Si(100)衬底上沿c轴方向生长单晶Zn1-xMgxO薄膜,通过X射线衍射(XRD)、原子力显微镜(AFM)、扫描电镜(SEM)和荧光光谱(PL)研究了膜厚、Mg含量、退火温度及氧气氛等制备工艺对Zn1-xMgxO薄膜的结构、形貌和光学性质的影响.实验结果表明,Mg含量x≤0.15时,Zn1-xMgxO保持六角纤锌矿结构,0.25≤x≤0.35时为立方结构,经过600℃退火之后,Zn0.75Mg0.25O转化为六角纤锌矿结构;后续退火有利于晶粒长大,一定的氧气氛也有利于减少晶体缺陷和薄膜的c轴应力,但是过量的氧气容易与Mg元素结合形成MgO,不利于ZnO六角纤锌矿结构的生长.对Zn0.925Mg0.075O薄膜进行荧光光谱分析,分析结果表明缺陷发光峰主要与锌空位、锌位氧(OZn)或氧间隙(Oi)等缺陷有关,退火可以使紫外发射峰蓝移.
Single crystal Zn1-xMgxO thin films were grown along the c-axis on a single-crystal Si (100) substrate by pulsed laser deposition (PLD) method and characterized by XRD, AFM and SEM The effects of preparation conditions such as film thickness, Mg content, annealing temperature and oxygen atmosphere on the structure, morphology and optical properties of Zn1-xMgxO films were investigated by fluorescence spectroscopy (PL) .Experimental results show that when the content of Mg is less than or equal to 0.15, xMgxO to maintain hexagonal wurtzite structure, 0.25≤x≤0.35 cubic structure, after annealing at 600 ℃, Zn0.75Mg0.25O hexagonal wurtzite structure; subsequent annealing is conducive to grain growth, a certain oxygen atmosphere But also help to reduce the crystal defects and c-axis stress of the film, but excessive oxygen is easy to combine with Mg element to form MgO, which is unfavorable to the growth of ZnO hexagonal wurtzite structure.Furthermore, the fluorescence spectra of Zn0.925Mg0.075O thin film were analyzed, It is indicated that the defect luminescence peak is mainly related to defects such as zinc vacancies, zinc oxygen (OZn) or oxygen vacancies (Oi). Annealing can make the UV emission peak blue-shifted.