基于正交试验的单晶4H-SiC化学机械抛光工艺研究

Experimental study on chemical mechanical polishing process of single crystal 4H-SiC based on orthogonal test

为了实现单晶4H-SiC化学机械抛光材料去除最优效果,基于正交试验法开展抛光工艺优化试验,研究抛光压力、转速、抛光液流量和磨粒粒度等工艺参数对4H-SiC晶圆不同晶面材料去除率的影响规律。结果表明:相同工艺参数对不同晶面材料去除影响的显著程度不同,通过极差分析获得了Si面和C面的最优抛光工艺组合,并进行了验证;在设定抛光压力为15 N,转速为120 r/min,抛光液流量为60 mL/min,磨粒粒度为50 nm的硅溶胶抛光液时,Si面的材料去除率为225.00 nm/h;与Si面有所不同,C面的最优参数组合依次为15 N、80 r/min、90 mL/min、80 nm,此时C面的材料去除率为240.74 nm/h。

To achieve the optimal material removal effect of single crystal 4H-SiC chemical-mechanical polishing,polishing process optimization experiment is carried out based on the orthogonal experiment method.Then,the effect of polishing pressure,rotation speed,flow rate of polishing slurry,and abrasive particle size on material removal rate of 4H-SiC with different crystal faces is analyzed.Experiment result shows that the same parameters have different influences on material removal rate of different crystal surfaces.Moreover,the optimal polishing process combination of Si surface and C surface is obtained and it is verified through range analysis.When polishing pressure is 15 N,rotation speed is 120 r/min,slurry flow rate is 60 mL/min,and silicon dioxide particle size is 50 nm,the material removal rate of Si surface is 225.00 nm/h.However,the material removal rate of C surface is 240.74 nm/h,and the corresponding process parameters are 15 N,80 r/min,90 mL/min,and 80 nm respectively,which are different from those of Si surface.