Nano-finishing of the monocrystalline silicon wafer using magnetic abrasive finishing process

The monocrystalline silicon wafer is the key material for micro-electro-mechanical systems. The performance of these wafers depends on their surface and subsurface quality. This research aims to study the effect of process parameters on the reduction ratio rate in surface roughness (%ΔR˙) of monocrystalline silicon wafers during the magnetic abrasive finishing process using response surface methodology. The parameters studied are machining gap, rotational speed, abrasive size, and magnetic abrasive particle (MAP) size. Quadratic models are developed by applying Box-Behnken design. Also, experiments are carried out on the silicon wafer, and the results of surface roughness data are analyzed by using analysis of variance. The most significant factor on each experimental design response is identified. According to our findings, the maximum %ΔR˙ value and the best surface roughness of the silicon wafer achieve 3.70 and 31 nm, respectively. Furthermore, the material removal mechanism in wafers is investigated by using atomic force microscopy. Our observations show that both micro-fracture and micro-cutting mechanisms might happen, and it highly depends on polishing parameters.