Self-organized Nanostructures On SiO₂ Surface Induced By Low-energy Ion Bombardment At Oblique Incidence With Impurity Co-deposition

Low-energy ion bombardment is a promising method for micro/nano processing of self-organized nanostructures.As an effective means to control the ion-induced self-organization,impurity co-deposition has quickly become one of the hotspots in this field.However,the complexity of the kinetic mechanism of impurity co-deposition significantly limits its development.To this end,we studied several issues of self-organized nanostructures produced by ion bombardment with impurity co-deposition,focusing on the physical mechanism of its formation and exploring its potential optical application.The main research contents and results are as follows:1.The dependence of incident angle of ion beam,time and distance dependence of the self-organized nanostructures by ion bombardment with impurity co-deposition was studied.It was found that the impurity co-deposition can not only promote the formation of nanostructures below the critical incidence angle of ion beam,but also can modulate the features of nanostructure above the critical incident angle of ion beam(typically above 30°).And such modulation effect is based on the guidance of pure ion-induced patterns.Combined with physical and chemical characterization methods and simulations,the physical mechanism of impurity’s modulation effect was studied.It was proved that the modulation effect mainly comes from the action of geometric factors and cannot be explained simply by the traditional impurity concentration theory.These studies have further expanded the theory of physical mechanisms of impurity co-deposition.2.The enhancement effect of impurity co-deposition on terracing process of nanostructures was studied.The results show that the impurity co-deposition has the effect of amplifying the amplitude of the self-organized nanostructures,which accelerates the pattern evolution into the nonlinear phase and finally enhances the terracing process.Combined with physical and chemical characterization methods,it was proved that the amplitude amplification effect of impurity co-deposition comes from shadow effect and phase separation.These studies prove impurity co-deposition to be an effective means of solving the bottleneck problem in pure ion-induced terrace nanostructures,which lays a foundation for the application of terrace nanostructures.3.The optical properties of self-organized nanostructures induced by ion bombardment with impurity co-deposition were preliminarily studied.It was found that the self-organized nanostructures produced in our experiment has anti-reflection properties in the ultraviolet band.The physical mechanism of the optical properties was discussed in the combination with theoretical simulations.It was found that the antireflection properties of the structure mainly come from the gradient effect of the refractive index.These results demonstrate the optical potential of ion-induced self-organized nanostructures with impurity co-deposition,which lays the foundation for the optical application of this technology in the future.