Correlation of wafer backside defects to photolithography hot spots using advanced macro inspection
Correlation of wafer backside defects to photolithography hot spots using advanced macro inspection
复制标题
使用先进的宏观检测将晶圆背面缺陷与光刻热点关联起来
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
Tuan D. Le
中科院分区：
文献类型：
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作者：
A. Carlson;Tuan D. Le
在处理期间晶片背面上的缺陷可来自许多来源。晶圆背面的颗粒和划痕可能由晶圆处理设备（如机器人和卡盘）以及CMP工艺引起。此外，当晶片通过生产线从一个工具移动到另一个工具时，可能发生晶片和处理设备的交叉污染。当晶片被曝光时，背面缺陷可在晶片的正面上引起光刻图案分辨率差的局部区域，从而导致返工率增加、产量降低和产量损失。随着最小特征尺寸随着每个新技术节点的不断缩小，器件变得更密集，曝光工具的焦深减小，使得消除光刻热点成为一个更加关键的问题。在全球主要IDM中，已经实施了用于集成正面、边缘和背面检测的自动宏观缺陷检测工具，以在多个显影后检测（ADI）和蚀刻后检测步骤中检测晶圆。这些工具已用于检测由另一种工艺工具引起的几个批次背面的异物和划痕，从而导致光刻热点。本文介绍了先进的宏观检测晶圆正面和背面，以及如何使用检测数据来关联背面缺陷光刻热点，并采取纠正措施。
Defects on the backside of a wafer during processing can come from many sources. Particles and scratches on the backsides of wafers can be caused by wafer handling equipment such as robots and chucks, as well as by CMP processes. In addition, cross-contamination of wafers and handling equipment can occur when wafers move from tool to tool, through the production line. When wafers are exposed, backside defects can cause localized areas of poor lithography pattern resolution on the frontsides of wafers, resulting in increased rework rates, decreased throughput, and yield loss. As minimum feature sizes continue to shrink with each new technology node, devices become denser and exposure tool depth of focus decreases - making the elimination of lithography hot spots an even more critical issue. At a major worldwide IDM, automated macro defect inspection tools for integrated front, edge, and backside inspection have been implemented to inspect wafers at several After Develop Inspection (ADI) and post-etch inspection steps. These tools have been used to detect foreign material and scratches on the backsides of several lots that were caused by another process tool, causing photolithography hot spots. This paper describes advanced macro inspection of wafer front and back surfaces and how the inspection data was used to correlate backside defects to photolithography hot spots, and take corrective action.