Abstract. Background: Reliable photomask metrology is required to reduce the risk of yield loss in the semiconductor manufacturing process as well as for the research on absorber materials. Actinic pattern inspection (API) of EUV reticles is a challenging problem to tackle with a conventional approach. For this reason, we developed RESCAN, an API platform based on coherent diffraction imaging. Aim: We want to verify the sensitivity of our platform to absorber and phase defects. Approach: We designed and manufactured two EUV mask samples with absorber and phase defects, and we inspected them with RESCAN in die-to-database mode. Results: We reconstructed an image of an array of programmed absorber defects, and we created a defect map of our sample. We inspected two programmed phase defect samples with buried structures of 3.5 and 7.8 nm height. Conclusions: We verified that RESCAN, in its current configuration, can detect absorber defects in random patterns and buried (phase) defects down to 50  ×  50  nm2.

中文翻译：

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使用相干衍射成像定量表征 EUV 掩模版上的吸收体和相位缺陷

摘要。背景：需要可靠的光掩模计量来降低半导体制造过程中的产量损失风险以及对吸收材料的研究。EUV 光罩的光化图案检测 (API) 是一个用传统方法解决的具有挑战性的问题。为此，我们开发了 RESCAN，一个基于相干衍射成像的 API 平台。目的：我们想要验证我们的平台对吸收体和相位缺陷的敏感性。方法：我们设计并制造了两个具有吸收体和相位缺陷的 EUV 掩模样品，并在 die-to-database 模式下使用 RESCAN 对其进行检查。结果：我们重建了一系列程序化吸收器缺陷的图像，并创建了样本的缺陷图。我们检查了两个具有 3.5 和 7.8 nm 高度的掩埋结构的编程相位缺陷样品。