Mapping the Edge-Roughness of Test Structure Features for Nanometer-Level CD Reference-Materials

Published

April 2, 2009

Author(s)

Michael W. Cresswell, M Davidson, Geraldine I. Mijares, Richard A. Allen, Jon C. Geist, M R. Bishop

Abstract

The near-term objective of the work reported here is developing a protocol for rapidly mapping CD and edge roughness from high-resolution SEM images of reference-material features patterned on SCCDRM chips. The longer term mission is to formulate a metric to enable automated characterization of as-fabricated reference-feature segments for rapid identification of fabrication-process enhancements and, ultimately, to select feature segments for further characterization as standard reference-materials. The selection of results presented here provides a new level of SCCDRM characterization which shows that segments of some SCCDRM features appear to have very useful extended lengths of up to 200 nm of superior CD uniformity. In general, however, these segments have no predictable spatial distribution. A major unintended benefit of the results that have been generated is that we may have acquired some useful insight for understanding the etching process that is used to pattern the features. We have observed that a) the most uniform feature segments tend to have the highest local CDs along a feature length and b) such CDs tend to have the same values. As a result, a model for the generation the non-uniformity of the CD, which in principle might be expected to be quasi-atomically uniform, is that the starting material may have nanometer-scale regions, which, for an as-yet unknown reason, destroy local etch anisotropy and accelerate silicon dissolution.

Proceedings Title

Proceedings of the 2009 International Conference on Microelectronic Test Structures

Conference Dates

March 30-April 2, 2009

Conference Location

Oxnard, CA

Conference Title

International Conference on Microelectronic Test Structures (ICMTS)

Pub Type

Conferences

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Keywords

Linewidth, Metrology, CD, SCCDRM, SRM, SEM, Edge roughness, Uncertainty

Citation

Cresswell, M. , Davidson, M. , Mijares, G. , Allen, R. , Geist, J. and Bishop, M. (2009), Mapping the Edge-Roughness of Test Structure Features for Nanometer-Level CD Reference-Materials, Proceedings of the 2009 International Conference on Microelectronic Test Structures, Oxnard, CA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=901520 (Accessed May 6, 2024)