蓝宝石表面纳米结构随杂质靶距离的演化

使用微波回旋共振离子源刻蚀蓝宝石(C向)表面,引入金属不锈钢杂质,研究了不同靶距处蓝宝石表面自组织纳米结构的演化规律及光学性能。采用原子力显微镜来观察样品表面的形貌变化,Taylor Surf CCI 2000白光干涉表面测量仪测量蓝宝石样片表面的粗糙度;选择X射线光电子能谱对样品表面的化学成分进行了表征。实验结果表明:当离子束能量为1000 eV,束流密度为487μA/cm²,入射角度为65°,刻蚀时间为60 min,蓝宝石样片与杂质靶距离从1 cm增加到4 cm时,样片表面出现岛状结构并逐渐演变为连续的条纹结构。同时,自组织纳米结构随靶距增加,有序性增加,纵向高度逐渐减小,空间频率基本不变。刻蚀后样品表面的金属杂质残留很少,微结构的形成对蓝宝石具有增透作用。在离子束溅射过程中,岛状结构的出现促进了样品表面条纹纳米结构的生长,破坏了纳米结构的有序性。

Evolution of sapphire surface nanostructure with distance of impurity target

Electron cyclotron resonance ion source has been employed to etch the surface of sapphire (C-cut), introducing metallic stainless steel impurities to investigate the evolution law and optical properties of the self-organized nanostructure on the sapphire surface at different target distances. The atomic force microscope was used to observe the morphological changes of the sample surface, the Taylor Surf CCI 2000 white light interference surface measuring instrument was used to measure the surface roughness; X-ray photoelectron spectroscopy was selected to characterize the chemical composition. The experimental results indicate that, with the ion beam energy of 1000 eV, the beam current density of 487 μA/cm2, the oblique incident angle of 65°, and the erosion duration of 60 min, the distance between the sapphire sample and the impurity target increases from 1 cm to 4 cm, island-like structures appear on the sample surface and gradually evolve into continuous ripple structures. At the same time, as the target distance increases, the orderliness of the self-organized nanostructures enhances, the longitudinal height gradually decreases, while the spatial frequency is unchanged. There are very few metal impurities on the etched sample surface. The appearance of microstructures has antireflection effect on sapphire. During the ion beam sputtering process, island-like structures promotes the growth of ripple nanostructures but destroys orderliness.