利用双磁极平面磁力研磨法对单晶硅表面的抛光实验研究

Studyon Polishing Experiment of Single Crystal Silicon Surface by Using Dual-pole Planar Magnetic Abrasive Finishing Method

为实现单晶硅表面平坦化,提出双磁极磁力研磨法(DMAF),并设计一套双磁极磁力研磨装置。探究双磁极磁力研磨法的加工机理,明确关键加工参数对单晶硅表面质量的影响,通过单因素对比实验对加工参数进行优化;利用ANSYS MAXWELL有限元软件,对传统平面磁力研磨法与双磁极磁力研磨法的磁场强度进行模拟仿真,对比两种方法在加工区域形成的磁感应强度,以实现定量分析磁性磨料粒子的研磨压力。基于单因素实验结果,确定了双磁极磁力研磨法对单晶硅片表面加工优化后的研磨参数:磨料组合为#200电解铁粉(Fe_(3)O_(4))+#8000白刚玉(White abrasive,WA),磁极间隙为12 mm,磁极转速为300 r/min,磨料质量比为3∶1。结果表明:在优化的研磨参数条件下,研磨60 min后的单晶硅片的平均表面粗糙度由初始的0.578μm降至8 nm,在研磨区域基本实现了镜面加工效果。仿真结果表明:与传统平面磁力研磨法相比,双磁极磁力研磨法可显著提高加工区域的磁感应强度,该研磨法所产生的磁场强度约为传统磁力研磨法的1.5倍。

The dual-pole magnetic abrasive finishing method(DMAF)is proposed for the surface planarization of single crystal silicon,and a set of dual-pole magnetic abrasive finishing device is designed.The processing mechanism of DMAF is explored,the effects of the key machining parameters on the surface quality of single crystal silicon is clarified and the machining parameters through single-factor comparative experimentsis optimized.By using ANSYS MAXWELL finite element software to simulate the magnetic field intensities in both traditional planar magnetic abrasive finishing method and DMAF,the magnetic induction intensity in the finishing area produced in two different finishing methods were compared to obtain the quantitative analysis of the finishing pressure of magnetic abrasive particles.According to the results of single-factor experiments,the optimizedpolishing parameters obtained in DMAF of the surface polishing of single crystal silicon wafers were in the following:the abrasive combination of#200Fe_(3)O_(4)+#8000WA,the gap of magnetic poles at 12 mm,magnetic pole speed at 300 r/min,and abrasive mass ratio at 3:1.It was indicated in the experimental results that with the optimal machining parameters,the single crystal silicon wafers reached their average surface roughness as low as 8 nm from the initial 0.578μm after 60 min finishing,and the workpiecein the polishing area almost achieveda mirror finishing effect.The simulation results show that comparing with the traditional plane magnetic abrasive finishing method,the DMAF can significantly improve the magnetic field intensity of the processing area,and the intensity produced in DMAF is about 1.5 times that in the traditional magnetic finishing method.