14 March 2018 Photoresist and stochastic modeling
Author Affiliations +
J. of Micro/Nanolithography, MEMS, and MOEMS, 17(1), 013506 (2018). doi:10.1117/1.JMM.17.1.013506
Analysis of physical modeling results can provide unique insights into extreme ultraviolet stochastic variation, which augment, and sometimes refute, conclusions based on physical intuition and even wafer experiments. Simulations verify the primacy of “imaging critical” counting statistics (photons, electrons, and net acids) and the image/blur-dependent dose sensitivity in describing the local edge or critical dimension variation. But the failure of simple counting when resist thickness is varied highlights a limitation of this exact analytical approach, so a calibratable empirical model offers useful simplicity and convenience. Results presented here show that a wide range of physical simulation results can be well matched by an empirical two-parameter model based on blurred image log-slope (ILS) for lines/spaces and normalized ILS for holes. These results are largely consistent with a wide range of published experimental results; however, there is some disagreement with the recently published dataset of De Bisschop. The present analysis suggests that the origin of this model failure is an unexpected blurred ILS:dose-sensitivity relationship failure in that resist process. It is shown that a photoresist mechanism based on high photodecomposable quencher loading and high quencher diffusivity can give rise to pitch-dependent blur, which may explain the discrepancy.
© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
Steven G. Hansen, "Photoresist and stochastic modeling," Journal of Micro/Nanolithography, MEMS, and MOEMS 17(1), 013506 (14 March 2018). https://doi.org/10.1117/1.JMM.17.1.013506 Submission: Received 6 October 2017; Accepted 16 February 2018
Submission: Received 6 October 2017; Accepted 16 February 2018

Stochastic processes


Photoresist processing

Data modeling

Line edge roughness

Critical dimension metrology

Photoresist materials

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