Study On Material Removal Mechanism Of Hard Brittle Crystal By Ultrasound Atomization Chemical Mechanical Polishing

With the rapid development of IC industry, semiconductor industry status become more and more higher, and the monocrystalline silicon is the main material of semiconductor, so the requirement of monocrystalline silicon surface quality also become more and more higher.Chemical mechanical polishing technology is one of the important technology of realizing the global smooth silicon wafer surface, but with the higher and higher demand of integrated circuit industry to the surface quality of single crystal silicon, the traditional chemical mechanical polishing technology can not meets the requirement of monocrystalline silicon surface quality gradually. And put forward the atomization liquid application mechanical polishing technology in order to solve this problem, which improve the shortcomings of traditional chemical-mechanical polishing techniques greatly. But at the moment, the research of material removal mechanism of atomization liquid application mechanical polishing technology is not yet mature, so that needing to do more in-depth research in the material removal mechanism of the atomization liquid application mechanical polishing, to further improve the quality of the surface of single crystal silicon.Purpose of research on the mechanism of mechanism and chemistry in CMP procedure,studying the effects of individual chemical and mechanical action on the material removal rate,And through study on the effect of polishing pressure, fog fluid flow, oxidant concentration and polishing pad rotating speed on the material removal rate. The research achievement shows that the atomizing slurry applied polishing system is the process of the combination of chemical and mechanical action. Alone increases polishing pressure, fog fluid flow, oxidant concentration or polishing pad rotating speed either factor, obtain the material removal rate increased, chemical and mechanical action is a function of mutual coordination.Purpose of study the effect of atomizing slurry applied chemical mechanical polishing process parameters on the polishing effect. Take rotating speed of polishing pad, polishing pressure, voltage of the atomizer and antioxidant quality score as factors. Take material removal rate(MRR) and surface roughness as evaluation to design orthogonal Experiment.And then do visually analyze and weight matrix analysis to the test results. Get the influence of various factors on the test results of the trend and degree, and get the best combination of parameters. The results show that the atomization process of liquid polishing polishing effect with rotating speed of polishing pad increases; first increases and then decreases with the increase of polishing pressure; Along with the atomizer voltage increases; Increases with the increase of antioxidant quality score. Order and influence degree from large to small is antioxidant quality score, polishing pressure, voltage of the atomizer, rotating speed of polishing pad. When the rotating speed of polishing pad is 60r/min, polishing pressure 6psi,voltage of the atomizer is 55 V, antioxidant quality score is 2.5wt%. Get material removal rate and surface roughness are the best, and the polishing effect is best.Establishing the trajectory equation of particles in the surface of wafer, And get specific impact of various parameters on the particle trajectory during the polishing by using MATLAB software simulate the particle trajectory under different parameters. Then, on thebasis of a single grain trajectories simulation, using MATLAB software simulate the more particle trajectory which in the surface of wafer at the same time, The results show that particle do periodic motion in the surface of wafer, The polishing pad speed and arm swing angular velocity have a significant impact on polishing effect, And the swing arm angle and length had no significant effect on the material removed.Further establishing mathematical model of material removal which consider the chemical and mechanical action, on the basis of the trajectory equation of particle in the surface of wafer, And combined with the results of single factor experiment to verify the exactness of the model.