Research On SiC Material Under The Regulation Of Electrostatic Effect

With the rapid development of semiconductor electronic devices,space optical mirrors,automotive industry and aerospace,silicon carbide materials have been widely used in various fields due to their good mechanical properties and chemical stability.However,silicon carbide materials have high hardness,high brittleness,and are prone to damage during processing.Chemical mechanical polishing(CMP)can improve material removal rate and surface quality of polished workpieces.Therefore,research on chemical mechanical polishing(CMP)is of great significance.Chemical mechanical polishing techniques,including mechanical and chemical interactions,are the result of a combination of both.In this paper,the effects of mechanical action and chemical mechanical synergy on the removal rate of silicon carbide and the quality of polished surface were studied.The main research work of this paper is as follows:(1)Selection and optimization of polishing process parameters.In the polishing experiment,the processing parameters affect the material removal rate and surface quality.Therefore,in order to analyze the influence of various process parameters on the polishing process during the polishing process,a polishing experiment was carried out to study the material removal rate and surface quality when the parameters such as pressure,rotation speed and abrasive grains were changed respectively,and the polishing law under different parameter changes was obtained.Process optimization.(2)The principle of electrostatic regulation.The electrolyte added to the polishing solution affects the electric double layer structure,which in turn affects the material removal rate.Therefore,based on the interaction force between the colloids,the electric double layer force between different surfaces is derived based on the Poisson-Boltzmann model,and the force model under the action of DLVO is established to calculate the Debye under different electrolyte conditions.Length,the effect of changing the concentration of the electrolyte and the composition on the electric double layer force is obtained.(3)Chemical mechanical action synergistic experiment.During the removal of the material,the composition of the polishing fluid affects the rate of material removal.The chemical composition in the polishing fluid is changed to coordinate chemical and mechanical interactions.The surface modification mechanism of silicon carbide was studied.The modification experiment of silicon carbide was carried out to study the thickness and hardness of the modified layer when the parameters such as time,time and concentration were changed respectively,so as to analyze the influence of the modification process on the material removal rate;The concentration and type of electrolyte were investigated for their effect on removal rate.By observing the change in the material removal rate,it is verified that the material removal rate is higher when the chemical action and the mechanical action are simultaneously present.(4)The effect of electrolyte on the polishing fluid.The electrolyte added to the polishing liquid has an effect on the state of the abrasive grains.Based on the study of the interaction force between colloids,the effects of different electrolyte concentrations and types on the particle size and particle size distribution in the polishing solution,and the effects of electrolyte on the particle size and particle size distribution in the polishing solution were studied.The surface quality after polishing was analyzed to obtain the influence of the polishing liquid under different electrolyte conditions on the roughness of the polished silicon carbide surface.