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

金刚石丸粒（DP）预计是用于固定磨料研磨方法的有效工具。然而，以前很少有在低研磨速度下使用DP的报道，例如，在四向固定磨料研磨系统中。因此，本研究旨在探讨低研磨速度下，单DP研磨的特性。本研究探讨了研磨量和DP研磨距离与以下参数的相关性：DP直径，DP磨损特性，研磨速度，研磨效率和研磨时间。结果表明，DP研磨距离与效率之间没有很强的相关性。然而，观察到DP磨损和效率之间的弱相关性。此外，本研究提出了一种方法，使最佳的研磨板/抛光布槽率在半径方向上的4路晶圆系统。采用遗传算法减小了硅片表面相对摩擦距离的偏差。在遗传算法中，以各计算条件下相对摩擦距离的最大偏差作为优化拟合函数的依据。研究结果表明：（1）工件的研磨轮廓取决于工件的十字形截面轮廓。(2)通过优化DP布局和减小DP直径，最大偏差显著减小。（3）通过一系列的实验验证了DP布局优化的有效性。

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.