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http://dx.doi.org/10.9725/kstle.2016.32.4.119

Effects of Groove Shape Dimension on Lapping Characteristics of Sapphire Wafer  

Lee, Taekyung (Korea Institute of Industrial Technology)
Lee, Sangjik (Korea Institute of Industrial Technology)
Jeong, Haedo (School of Mechanical Engineering, Pusan National University)
Kim, Hyoungjae (Korea Institute of Industrial Technology)
Publication Information
Tribology and Lubricants / v.32, no.4, 2016 , pp. 119-124 More about this Journal
Abstract
In the sapphire wafering process, lapping is a crucial operation in order to reduce the damaged layer and achieve the target thickness. Many parameters, such as pressure, velocity, abrasive, slurry and plate, affect lapping characteristics. This paper presents an experimental investigation on the effect of the plate groove on the material removal rate and roughness of the wafer. We select the spiral pattern and rectangular type as the groove shapes. We vary the groove density by controlling the groove shape dimension, i.e., the groove width and pitch. As the groove density increases to 0.4, the material removal rate increases and gradually reaches a saturation point. When the groove density is low, the pressing load is mostly supported by the thick film, and only a small amount acts on the abrasives resulting to a low material removal rate. The roughness decreases on increasing the groove density up to 0.3 because thick film makes partial participations of large abrasives which make deep scratches. From these results, we could conclude that the groove affects the contact condition between the wafer and plate. At the same groove density, the pitch has more influence on reducing the film thickness than the groove width. By decreasing the groove density with a smaller pitch and larger groove width, we could achieve a high material removal rate and low roughness. These results would be helpful in understanding the groove effects and determining the appropriate groove design.
Keywords
sapphire wafer; lapping; groove; material removal rate; shape dimension;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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