Experimental Study On Ultra-smooth Surface Simulator Of Optical Monocrystalline Silicon By Optically Coupled Colloid Jet

With the continuous development of the field of optics and microelectronics,strict standards have been put forward on the surface properties of optical parts such as surface precision,resolution,stability and morphology,especially for the surface topography of optical components.It is required to have no surface damage and nanometer-scale surface roughness.At present,in the field of optical manufacturing,complex surfaces are more and more widely used in the market due to their own significant advantages,but it is followed by how to realize the large-scale processing and manufacturing of aspherical ultra-smooth surfaces.To this end,researchers in the field of optical processing in the world are committed to the development of new ultra-smooth surface processing technology,in order to achieve the formation of ultra-smooth surfaces of various complex curved optical components.Based on the UV-induced nanoparticle colloid jet processing technology,the TiO₂ nanoparticles in the colloid environment and the Si at the surface structure of the two single crystal silicon were processed during the ultra-smooth surface processing of the photo-coupled TiO₂ nanoparticle colloid jet.The interaction between atoms and the subsequent atomic bond breaks at the single crystal silicon interface were studied by a combination of simulation and experiment.The formation mechanism of ultra-smooth surface of colloid jet monocrystalline silicon under optical coupling was analyzed.Since the photocoupled colloid jet processing relies on a series of chemical reactions between the nanoparticles in the colloid and the surface of the surface to be processed under the action of the light field and the jet flow field to achieve atomic level removal of the surface of the material,quantum is needed.The chemical research method simulates and calculates the specific reaction paths and energy changes of various molecules and atoms in the polishing process.Firstly,the quantum chemical calculation method is described in detail,and the methods used in the simulation process are introduced one by one.The major research efforts include the following points:?1?The behavioral path between nanoparticles and atoms on the surface of single crystal silicon was studied in a colloid environment.On the basis of quantum chemical calculation,the anatase TiO₂ model and its cluster model and the"flat"and"convex"surface models of single crystal silicon were established by Material Studio software.The CASTEP plate was used to simulate the adsorption process of OH groups and anatase TiO₂ clusters,OH groups and single crystal silicon surface,anatase TiO₂ clusters and single crystal silicon surface.The difficulty of chemical adsorption of the two single crystal silicon surface structures by the cluster and TiO₂cluster model.Finally,when the TiO₂ clusters are separated from the two single crystal silicon surface structures,the energy required for the surface Si-Si bond cleavage is carried out.The simulation results show that the interfacial reaction between the TiO₂ nanoparticles and the surface of the single crystal silicon workpiece during the ultra-smooth surface processing of the photo-coupled TiO₂ nanoparticle colloid jet-generated single crystal silicon is mainly the bonding between atoms,which is a light-coupled colloid jet.The theoretical basis for the ultra-smooth surface mechanism of the created single crystal silicon.?2?The photocatalytic activity of the prepared TiO₂ nanoparticle colloid was analyzed.X-ray diffraction?XRD?was performed on the TiO₂ nanoparticle powder,and the TiO2 nanoparticle colloid was prepared by using the powder.The TiO₂nanoparticles in the colloid were characterized by particle size analysis by nanoparticle size analyzer and transmission electron microscope?TEM?.Then,the prepared colloid was subjected to a photocatalytic activity comparison experiment of degrading methyl orange solution.?3?A photocoupled colloid jet polishing test was performed on a single crystal silicon wafer.Ultraviolet-induced nanoparticle colloid jet polishing test was carried out on the surface of single crystal silicon workpiece by a good jet processing platform independently developed by the research group.The surface morphology of single crystal silicon before and after jet processing was detected by atomic force microscopy?AFM?.The results show:The optically coupled jet polished single crystal silicon workpiece obtained an ultra-smooth surface with a sub-nanometer level.?4?The first-principles simulation results were verified by adsorption comparison experiments.According to the results of quantum chemical simulation,a new Ti-O-Si covalent bond was formed after the chemical collision between the TiO₂nanoparticles in the colloid and the surface of the single crystal silicon.In order to verify the simulation results,the TiO₂ nanoparticles were designed in single crystal.Adsorption experiments on silicon surfaces.The surface of single crystal silicon after jet processing,the scanning electron microscope?SEM?characterization results of the surface of single crystal silicon after adsorption experiments and the surface of single crystal silicon without any treatment,and the infrared reflection spectra of the three were compared.The chemical adsorption of the surface of the single crystal silicon with the TiO₂ nanoparticles does form a new common bond on the surface of the single crystal silicon.