Actinic critical dimension measurement of contaminated extreme ultraviolet mask using coherent scattering microscopy

Jae Uk Lee, Seongchul Hong, Jinho Ahn, Jonggul Doh, Seejun Jeong

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The authors evaluated the feasibility of using coherent scattering microscopy (CSM) as an actinic metrology tool by employing it to determine the critical dimension (CD) and normalized image log-slope (NILS) values of contaminated extreme ultraviolet (EUV) masks. CSM was as effective as CD scanning electron microscopy (CD-SEM) in measuring the CD values of clean EUV masks in the case of vertical patterns (nonshadowing effect); however, only the CSM could detect shadowing effect for horizontal patterns resulting in smaller clear mask CD values. Owing to weak interaction between the low-density contaminant layer and EUV radiation, the CSM-based CD measurements were not as affected by contamination as were those made using CD-SEM. Furthermore, CSM could be used to determine the NILS values under illumination conditions corresponding to a high-volume manufacturing tool.

Original languageEnglish
Article number031601
JournalJournal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
Volume32
Issue number3
DOIs
StatePublished - 2014 Jan 1

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Coherent scattering
coherent scattering
Masks
Microscopic examination
masks
microscopy
Scanning electron microscopy
slopes
extreme ultraviolet radiation
scanning electron microscopy
Ultraviolet radiation
Contamination
metrology
Lighting
contaminants
Impurities
contamination
manufacturing
illumination

Cite this

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Actinic critical dimension measurement of contaminated extreme ultraviolet mask using coherent scattering microscopy. / Uk Lee, Jae; Hong, Seongchul; Ahn, Jinho; Doh, Jonggul; Jeong, Seejun.

In: Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures, Vol. 32, No. 3, 031601, 01.01.2014.

Research output: Contribution to journalArticle

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