Measurement sensitivity of DUV scatterfield microscopy parameterized with partial coherence for duty ratio-varied periodic nanofeatures

Published

February 1, 2022

Author(s)

Taekyung Kim, Eikhyun Cho, Yoon Sung Bae, Sang-Soo Choi, Bryan Barnes, Richard M. Silver, Martin Sohn

Abstract

The deep ultraviolet (DUV) scatterfield imaging microscopy technique enables accurate dimensional measurements of periodic nanostructures with sub-nanometer sensitivity to support semiconductor device manufacturing. A parametric sensitivity analysis for targets with uneven duty ratios is essential as the duty ratios of many periodic nanostructures vary practically. This paper presents an experimental implementation to optimize illumination condition for nanoscale multiline targets on a Molybdenum Silicide (MoSi) photomask with duty ratios of 0.43 – 0.68 using a scatterfield imaging microscope with 193 nm wavelength laser designed for resolved illumination at the sample. Measurement sensitivities are analyzed using sensitivity coefficient maps parameterized with partial coherence factor, the duty ratio of the target, and the incident polarization.

Citation

Optics and Lasers in Engineering

Volume

152

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.optlaseng.2022.106953

Local Download

Keywords

Scatterfield microscopy, measurement sensitivity, partial coherence, critical dimension, duty ratio

Citation

Kim, T. , Cho, E. , Bae, Y. , Choi, S. , Barnes, B. , Silver, R. and Sohn, M. (2022), Measurement sensitivity of DUV scatterfield microscopy parameterized with partial coherence for duty ratio-varied periodic nanofeatures, Optics and Lasers in Engineering, [online], https://doi.org/10.1016/j.optlaseng.2022.106953, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932950 (Accessed April 19, 2024)