A Study for Ultra Precision Processing of Silicon Wafer by Lapping Stone

By New Lapping Stone instead of Free Abrasive Lapping Process

Abstract

This paper deals with some experimental results of the application of a newly developed PVA grinding stone to the lapping process of silicon wafer. The characteristics of the developed grinding stone are, about 30 vol% abrasive content, about 25 vol% resin content and about 45 vol% porosity, and by changing the flow rate of lapping fluid, experimental results are largely changed. Lower flow rate gives higher removal rate and coarser surface roughness similar to the free abrasive lapping process, and the higher flow rate gives lower removal rate and finer surface roughness. The depth of distorted layer is thinner and the surface of lapped wafer is cleaner than that of by free abrasive lapping process.