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Publication Citation: High-Accuracy Critical-Dimension Metrology Using a Scanning Electron Microscope

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Author(s): J R. Lowney; Andras Vladar; Michael T. Postek;
Title: High-Accuracy Critical-Dimension Metrology Using a Scanning Electron Microscope
Published: May 01, 1996
Abstract: Two Monte Carlo computer codes have been written to simulate the transmitted-, backscattered-, and secondary-electron signals from targets in a scanning electron microscope. The first discussed, MONSEL-II, is applied to semi-infinite lines produced lithographically on multi-layer substrates. The second discussed, MONSEL-III, is an extension to fully three-dimensional targets. Results are given for a 1 micrometer step etched in a silicon substrate and compared with experimental data. The comparisons show that it is possible to obtain edge locations to an uncertainty of less than 10 nm. Simulations are also given for photoresist lines on a silicon substrate coated with a layer of photoresist. Techniques are developed for simulating signals for finite beam diameter from those for zero beam diameter, and for extracting signals approximating zero beam diameter from those with finite beam diameter.
Proceedings: Proceedings of SPIE, Metrology, Inspection, and Process Control for Microlithography X, Susan K. Jones, Editor
Volume: 2725
Pages: pp. 515 - 526
Location: Santa Clara, CA
Research Areas: Metrology, Manufacturing