关键词: 磨粒粒径；研磨均匀性；微裂纹；延性切削

Abstract:

Experiments were taken to investigate the effect of abrasive grain size on the lapping uniformity of sapphire wafer, macro and micro surface profiles were measured and compared by contact and contactless measurement methods. For W14 carbide boron abrasive lapping process, rolling and extruding effects are the main material removal process and leaves high density micro-crack on the lapped sapphire surface. On the other hand, W3.5 carbide boron abrasive grain performs a ductile cutting process for material remove process under the same operation parameters, only scratch on sapphire surface can be viewed by AFM. Experimental results show that abrasive grain size has a great effect on the surface integrity of the lapped sapphire, except the roughness to be achieved, the charging status of abrasive grain into the lapping plate and its effect on the surface integrity should be considered when choosing the abrasive grain size for precision lapping process. Lapping uniformity both for macro and micro level, roughness and flatness of sapphire wafer can be achieved by using W3.5 carbide boron abrasive grain and is acceptable by pre-polishing process.

Key words: abrasive grain size, lapping uniformity, micro-crack;ductile cutting