Abstract. Background: Continued shrinkage of pattern size has caused difficulties in detecting small defects. Multibeam scanning electron microscopy (SEM) is a potential method for pattern inspection below 7-nm node. Performance of the tool depends on charge control, resolution, and defect detection capability. Aim: The goal of this study is to develop a method for evaluating the performance of multibeam SEM for 7-nm nodes. Approach: By developing various standard samples with programmed defects (PDs) on 12 in. Si wafer, we evaluate the performance of multibeam SEM. Results: The first wafer had line and space (LS) patterns and PDs with varying contrast. A second wafer had various shaped small PDs, ∼5  nm in size in 16- to 12-nm half-pitch LS patterns. A third wafer with extremely small PDs of around 1 nm was fabricated in LS patterns with ultralow line-edge roughness (LER) of less than 1 nm. The first wafer was effective for charge control, whereas second and third wafer confirms resolution and defect detection capability. Conclusions: A set of minimum three standard wafer samples is effective to confirm the performance of multibeam SEM for below 7-nm nodes. Besides, we proposed a method to verify the LER values measured by a critical-dimension SEM.

中文翻译：

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开发带有程序缺陷的标准样品，用于评估 7 纳米和更小节点的图案检查工具

摘要。背景：图案尺寸的持续缩小导致了检测小缺陷的困难。多束扫描电子显微镜 (SEM) 是一种用于 7-nm 节点以下模式检测的潜在方法。该工具的性能取决于充电控制、分辨率和缺陷检测能力。目的：本研究的目的是开发一种评估 7 纳米节点多光束 SEM 性能的方法。方法：通过在 12 英寸硅晶片上开发各种具有程序缺陷 (PD) 的标准样品，我们评估了多光束 SEM 的性能。结果：第一块晶圆具有不同对比度的线和空间 (LS) 图案和 PD。第二个晶圆具有各种形状的小 PD，尺寸约为 5 nm，采用 16 至 12 nm 半间距 LS 图案。第三个具有约 1 nm 的极小 PD 的晶圆以 LS 图案制造，具有小于 1 nm 的超低线边缘粗糙度 (LER)。第一个晶片对电荷控制有效，而第二个和第三个晶片证实了分辨率和缺陷检测能力。结论：一组最少三个标准晶圆样品可以有效地确认多光束 SEM 对 7 纳米以下节点的性能。此外，我们提出了一种方法来验证由临界尺寸 SEM 测量的 LER 值。