Enhancing 9 nm Node Dense Patterned Defect Optical Inspection using Polarization, Angle, and Focus

Published

April 10, 2013

Author(s)

Bryan M. Barnes, Francois R. Goasmat, Martin Y. Sohn, Hui Zhou, Abraham Arceo

Abstract

To measure the new SEMATECH 9 nm node Intentional Defect Array (IDA) and subsequent small, complex defects, a methodology has been used to exploit the rich information content generated when simulating or acquiring several images of sub-wavelength-sized defects through best focus. These images, which are xy planes, collected using polarized illumination are stacked according to focus position, z, and through interpolation, volumetric pixels (“voxels”) are formed sized approximately 40 nm per side. From the image data, an intensity can be assigned to each (x,y,z) position. These four-dimensional matrices are extensively filtered for defect detection using multi-dimensional intensity thresholding, nearest-neighbor criteria, continuity requirements, and other techniques standard to optical defect inspection. A simulation example with oblique angles of illumination is presented. Experimental results are shown from the NIST 193 nm Microscope using full-field illumination. Volumetric data analysis is compared against the processing of single 2-D images. Defect metrics for comparing planar and volumetric data are developed with the potential shown for a five-fold increase in defect sensitivity using volumetric data versus conventional imaging.

Proceedings Title

Proceedings of the SPIE

Volume

8681

Conference Dates

February 24-28, 2013

Conference Location

San Jose, CA

Conference Title

Metrology, Inspection, and Process Control for Microlithography XXVII

Pub Type

Conferences

Download Paper

https://doi.org/10.1117/12.2012250

Keywords

Defect detection, Scatterfield optical microscopy, bright-field microscopy, dark-field microscopy, volumetric imaging

Citation

Barnes, B. , Goasmat, F. , Sohn, M. , Zhou, H. and Arceo, A. (2013), Enhancing 9 nm Node Dense Patterned Defect Optical Inspection using Polarization, Angle, and Focus, Proceedings of the SPIE, San Jose, CA, [online], https://doi.org/10.1117/12.2012250 (Accessed April 26, 2026)

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