Mn掺杂对ZnO薄膜结构及发光性能的影响

利用脉冲激光沉积的方法在Si衬底上生长出了c轴高度取向的Mn掺杂ZnO薄膜.X射线衍射表明所有样品都具有纤锌矿结构,没有发现其它相,随着掺杂量的增加,c轴晶格常数增大.原子力显微镜结果显示:Mn的掺杂引起了ZnO薄膜表面粗糙度的变化.由光致发光谱发现,在387 nm附近出现了由于近带边自由激子复合引起的紫外峰,还有以4...     

α-Al_2O_3衬底上6H-SiC薄膜的SSMBE外延生长

采用固源分子束外延(SSMBE)技术,在α-Al2O3(0001)衬底上直接制备出了SiC薄膜.利用反射式高能电子衍射(RHEED)、Raman光谱、X射线扫描、傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)等实验技术,对生长的样品的结构和结晶质量进行了表征.结果表明:在蓝宝石衬底上生长出了结晶性能良好的6H-SiC薄膜,且薄膜中存在较小的压应力,这种压应力是由薄膜与衬底之间热膨胀系数的差异所致.     

boldmath In situ high temperature X-ray diffraction studies of ZnO thin film

An epitaxial ZnO thin film was entirely fabricated by pulsed laser deposition. Both the orientation and the size of the crystallites were studied. The X-ray diffraction (XRD) patterns of the film show strong c-axis oriented crystal structure with preferred (002) orientation. The Phi-scan XRD pattern confirms that the epitaxial ZnO exhibits a single-domain wurtzite structure with hexagonal symmetry. In situ high-temperature XRD studies of ZnO thin film show that the crystallite size increases with increasing temperature, and (002) peaks shift systematically toward lower 2θ values due to the change of lattice parameters. The lattice parameters show linear increase in their values with increasing temperature.