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Optical volumetric inspection of sub-20 nm patterned defects with wafer noise



Bryan M. Barnes, Francois R. Goasmat, Martin Y. Sohn, Hui Zhou, Richard M. Silver, Andras Vladar, Abraham Arceo


We have previously introduced a new data analysis method that more thoroughly utilizes scattered optical intensity data collected during defect inspection using bright-field microscopy. This volumetric approach allows conversion of focus resolved 2-D collected images into 3-D volumes of intensity information and also permits the use of multi-dimensional processing and thresholding techniques to enhance defect detectability. In this paper, the effects of wafer noise upon detectability using volumetric processing are assessed with both simulations and experiments using the SEMATECH 9 nm node intentional defect array. The potential extensibility and industrial application of this technique are evaluated.
Proceedings Title
Proceedings of the SPIE
Conference Dates
February 23-27, 2014
Conference Location
San Jose, CA
Conference Title
Metrology, Inspection, and Process Control for Microlithography


wafer noise, defect inspection, volumetric processing, defect metrology, three-dimensional image processing


Barnes, B. , Goasmat, F. , Sohn, M. , Zhou, H. , Silver, R. , Vladar, A. and Arceo, A. (2014), Optical volumetric inspection of sub-20 nm patterned defects with wafer noise, Proceedings of the SPIE, San Jose, CA, [online], (Accessed June 12, 2024)


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Created April 2, 2014, Updated November 10, 2018