1 January 2009 Combinatorial overlay control for double patterning
Author Affiliations +
Abstract
The extension of optical lithography to 32 nm and beyond is dependent on double-patterning at critical levels. Double patterning adds degrees of freedom for overlay variation while reducing the allowed overlay tolerance. Overlay control requires the assessment and minimization of error among various mask/layer combinations. The possible overlay control combinations scale as Cn=(2n−1)2 with the number of reference layers n containing (x,y) alignment and overlay targets. Finding the optimum overlay control pathway requires that we employ the on-product means to examine multiple options compatible with the product overlay tolerances. The Blossom overlay target enables simultaneous determination of all combinations of patterns represented within the measurement tool field of view. We examine Blossom enabled use cases in double patterning overlay control as demonstrated at contact-to-gate registration on a 32 nm product.
© (2009) Society of Photo-Optical Instrumentation Engineers (SPIE)
Christopher P. Ausschnitt, Christopher P. Ausschnitt, Scott D. Halle, Scott D. Halle, } "Combinatorial overlay control for double patterning," Journal of Micro/Nanolithography, MEMS, and MOEMS 8(1), 011008 (1 January 2009). https://doi.org/10.1117/1.3023079 . Submission:
JOURNAL ARTICLE
8 PAGES


SHARE
RELATED CONTENT

Multilayer overlay metrology
Proceedings of SPIE (March 23 2006)
Multi-patterning overlay control
Proceedings of SPIE (March 16 2008)

Back to Top