Development of High Accuracy Process Technique in 4-way System Diamond Pellets Grinding

点击翻译按钮获取中文摘要

Diamond pellets (DP) are expected to be effective tools for use in fixed abrasive lapping methods. However, there have been few previous reports of use of DP at low lapping speeds, e.g., in 4-way fixed abrasive lapping systems. Therefore, this study was performed to investigate the single DP lapping characteristics at low lapping speed. This study examined the correlations of amount of lapping and DP lapping distance with the following parameters: DP diameter, DP wear characteristics, lapping speed, lapping efficiency, and lapping time. The results indicated that there are no strongly correlations between the DP lapping distance and efficiency. However, a weak correlation was observed between DP wear and efficiency. Furthermore, this study presents a method for making optimal lapping plate/polishing cloth groove rates in the radius direction for the 4-way wafer system. A genetic algorithm is used for decreasing the deviation of relative friction distance at wafer surface. The maximum deviation of relative friction distance under each calculation conditions is used for optimizing fitting function at the genetic algorithm. The results are as follows:(1) The lapping profiles of DP is depended on the cress sectional profile of DP.(2) The maximum deviation remarkably decreases by optimizing the DP layout and decreasing of DP diameter(3) The effectiveness about the optimization of DP layout were confirmed by a series of experimental examinations.