Abstract. Background: An extreme ultraviolet (EUV) pellicle is necessary to increase the process yield even though the declining throughput is a big concern. However, an EUV metrology/inspection tool for this pellicle has not been commercialized yet. Aim: The goal of this study is to verify the pellicle/mask inspection feasibility of EUV scanning lensless imaging (ESLI) and verify the impact of contaminants on pellicles depending on their size. Approach: Through-pellicle imaging was implemented by using ESLI, which uses a high-order harmonic generation EUV source and ptychography. Optical characteristics of various sizes of Fe-contaminated EUV pellicles were evaluated to verify their impact on wafer images. Results: Large size (∼10  μm) contaminants on the pellicle were found to contribute to the final wafer pattern loss. However, small size (2 to 3  μm) contaminants on the pellicle do not have substantial impact on the wafer image. Conclusions: The defect detection capability of ESLI for pellicle and mask was confirmed. Therefore, ESLI is useful in applications like pellicle qualification and EUV mask inspection metrology.

中文翻译：

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极紫外光罩的透膜成像与极紫外ptychography显微镜

摘要。背景：极紫外 (EUV) 薄膜对于提高工艺良率是必要的，尽管产量下降是一个大问题。然而，这种薄膜的 EUV 计量/检查工具尚未商业化。目的：本研究的目的是验证 EUV 扫描无透镜成像 (ESLI) 的防护膜/掩模检测可行性，并验证污染物对防护膜尺寸的影响。方法：通过使用 ESLI 实现透膜成像，ESLI 使用高次谐波产生 EUV 源和 ptychography。评估了各种尺寸的受 Fe 污染的 EUV 薄膜的光学特性，以验证它们对晶片图像的影响。结果：发现薄膜上的大尺寸（~10 μm）污染物会导致最终的晶圆图案损失。然而，薄膜上的小尺寸（2 到 3 μm）污染物对晶片图像没有实质性影响。结论：ESLI对防护膜和口罩的缺陷检测能力得到了证实。因此，ESLI 在防护膜鉴定和 EUV 掩模检测计量等应用中非常有用。