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用等离子辅助分子束外延(P-MBE)的方法,在蓝宝石c-平面上外延生长了Mg_xZn_(1-x)O合金薄膜。在0≤x≤0.2范围内Mg_xZn_(1-x)O薄膜保持着六角纤锌矿结构不变。原位反射式高能电子衍射图样和X射线双晶衍射谱的结果表明生长的样品是单晶薄膜。随着x值逐渐增大,Mg~(2+)离子逐渐进入ZnO的晶格,X射线双晶衍射测得样品的(002)取向的半高宽度从0.249°增加到0.708°,表明结晶质量逐渐下降,(002)方向的X射线衍射峰向大角度方向移动,晶格常数c由5.205减小到5.185。透射光谱的结果表明,合金薄膜的吸收边随着Mg离子的掺入逐渐向高能侧移动,室温光致发光谱出现很强的紫外发光(NBE)峰,没有观察到深能级(DL)发射,且随着Mg掺入量的增加,紫外发光峰有明显的蓝移,这与透射光谱的结果是相吻合的。
Mg_xZn_ (1-x) O alloy thin films were epitaxially grown on c-plane of sapphire by plasma assisted molecular beam epitaxy (P-MBE). The Mg_xZn_ (1-x) O thin film maintains hexagonal wurtzite structure in the range of 0≤x≤0.2. In situ reflection high energy electron diffraction patterns and X-ray double crystal diffraction spectrum results show that the growth of the sample is a single crystal film. As the value of x increases, the Mg 2+ ions gradually enter the lattice of ZnO. The half width of the (002) orientation of the sample increases from 0.249 ° to 0.708 ° as measured by X-ray double crystal diffraction, indicating that the crystalline quality Gradually decreased. The X-ray diffraction peak in (002) direction shifted to a large angle, and the lattice constant c decreased from 5.205 to 5.185. The results of transmission spectroscopy showed that the absorption edge of the alloy thin film shifted to the high energy side with the Mg ion incorporation, and the strong ultraviolet light (NBE) peak appeared in the photoluminescence spectrum at room temperature. No deep level (DL) emission was observed , And with the increase of Mg doping, there is a clear blue shift of the ultraviolet luminescence peak, which is consistent with the result of the transmission spectroscopy.