Molecular Dynamics Simulation And Experimental Research Of Glancing Angle Deposition

Three-dimensional and nanostructure devices are one of the core devices in thenanotechnology era. Glancing Angle Deposition (GLAD) has become the most potentialnanostructure processing method because of its high efficiency. However, the analysison its mechanism is far behind its practical research, which hampers its owndevelopment. Therefore, it’s of significant relevance to nanostructure designing andprocessing optimization to further study the mechanism of GLAD.In this thesis, we studied GLAD mechanism in many aspects based on moleculardynamics (MD). First of all, we found the MD simulation model for GLAD, and,through careful discussion, selected the parallel computing hardware platform of singlecomputer which not only provides high computing efficiency but is also economical.The accuracy of the model is proved in general. Meanwhile, we defined a statisticalmethod for deposited structure tilt angle, which is combined with Radial DistributionFunction Statistics (RDF) and Common Neighbor Analysis (CNA), to achieve furtheranalysis on the simulation result.Secondly, we carried out simulation and analysis on the GLAD on flat substrate.The result shows that there are different movement forms throughout the depositionprocess, which leads to different combination forms of the deposited structure and thesubstrate. Only through the decrease of deposition incident energy can we get depositedstructures of certain characteristics by utilizing the natural atom order. The tilt angle ofthe deposited structure equals to the real incident angle of the deposited atom. Thedeposited structures present different morphology and differentiation characteristicsunder different incident angles, which is a result of the different distribution of itsinternal defect layer; while the deposited structure nucleation is the result of theconnection and combination of dominant growing areas.Thirdly, simulation and analysis on the GLAD on template substrate was alsocarried out. We found that the growth of GLAD structure on single preseted substratestructure is affected by the deformation and damage of substrate structure and therestraint among dominant growth orientation on multiplane, leading to irregular growth.when the incident angle increasing by60degree, the orientation of defect layer ofdeposited structure changes, resulting in the difference from the case of GLAD structuregrowing on flat substrate. Shape and parameters of template substrate and motion formsof the substrate are all obvious influence in the morphology and distribution of GLADstructure.At last GLAD platform was built base on E-beam vapor deposition system, thenwe carried out GLAD experiment and analyzed the GLAD sample. The conclusion isthat basic GLAD structure can be prepared on the GLAD platform, and incident angle affects nanostructure and macrostructure of deposited structure visibly. The correctnessof MD simulation results are proved by qualitative compare between experimentalGLAD structure morphology and simulation results.