Removal Characteristics of Sapphire Lapping using Composite Plates with Consciously Patterned Resinoid-Bonded Semifixed Diamond Grits

Abstract

Sapphire lapping is of key importance for the successful planarization of wafers that are widely present in electronic devices. However, the high hardness of sapphire makes it extremely challenging to improve its material removal rate during the lapping process without compromising surface quality and dimensional accuracy. In this work, a novel composite lapping plate consisting of a rigid resin frame and flexible sol–gel balls was fabricated with consciously designed patterns. Through lapping experiment, it was revealed that the diamond grits imbedded in the sol–gel balls can effectively lap the sapphire at a promising material removal rate (MRR), without the formation of undesirable scratches and loss of surface integrity. Moreover, by designing the arrangement patterns of sol–gel balls, the total thickness variation (TTV) can also be ensured for lapped sapphire substrates. The implications of experimental results were also discussed based on the trajectory analysis and contact mechanics of lapping grits in order to demonstrate the potential of the newly developed composite abrasive tools for sapphire-lapping applications.

Processing performance of vitrified bonded fixed-abrasive lapping plates for sapphire wafers

“…Compared with the general lapping plate, the workpiece surface roughness has decreased by 12% and MRR has increased by 25%. Yun [18] and Fang et al [19,20] studied the influence of the form of arrangement of pellets on the lapping effect.…”

Effect of the Lapping Platen Groove Density on the Characteristics of Microabrasive-Based Lapping

“…The flatness of the substrate is represented by the total thickness variation (TTV), which is the difference between the maximum and minimum thicknesses in the measurement area [12][13][14]. These lapping characteristics are complexly influenced by various factors, such as the rotational speed of the platen, the pressing force, the slurry Micromachines 2020, 11, 775 2 of 13 properties, the lapping platen shape, the platen grooves density, etc. [15][16][17][18].…”