10 April 2013 Evaluating scatterometry 3D capabilities for EUV
Author Affiliations +
Optical critical dimension (OCD) metrology using scatterometry has been demonstrated to be a viable solution for fast and non-destructive in-line process control and monitoring. As extreme ultraviolet lithography (EUVL) is more widely adopted to fabricate smaller and smaller patterns for electronic devices, scatterometry faces new challenges due to several reasons. For 14nm node and beyond, the feature size is nearly an order of magnitude smaller than the shortest wavelength used in scatterometry. In addition, thinner resist layer is used in EUVL compared with conventional lithography, which leads to reduced measurement sensitivity. Despite these difficulties, tolerance has reduced for smaller feature size. In this work we evaluate 3D capability of scatterometry for EUV process using spectroscopic ellipsometry (SE). Three types of structures, contact holes, tip-to-tip, and tip-to-edge, are studied to test CD and end-gap metrology capabilities. The wafer is processed with focus and exposure matrix. Good correlations to CD-SEM results are achieved and good dynamic precision is obtained for all the key parameters. In addition, the fit to process provides an independent method to evaluate data quality from different metrology tools such as OCD and CDSEM. We demonstrate 3D capabilities of scatterometry OCD metrology for EUVL using spectroscopic ellipsometry, which provides valuable in-line metrology for CD and end-gap control in electronic circuit fabrications.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jie Li, Jie Li, Oleg Kritsun, Oleg Kritsun, Prasad Dasari, Prasad Dasari, Catherine Volkman, Catherine Volkman, Tom Wallow, Tom Wallow, Jiangtao Hu, Jiangtao Hu, "Evaluating scatterometry 3D capabilities for EUV", Proc. SPIE 8681, Metrology, Inspection, and Process Control for Microlithography XXVII, 86810S (10 April 2013); doi: 10.1117/12.2011675; https://doi.org/10.1117/12.2011675


Scatterometry metrology challenges of EUV
Proceedings of SPIE (April 04 2012)
Scatterometry for EUV lithography at the 22-nm node
Proceedings of SPIE (April 20 2011)
Scatterometry for contact hole lithography
Proceedings of SPIE (May 23 2004)
Reaching a CD uniformity of below 3 nm for 300...
Proceedings of SPIE (May 09 2005)
Metrology requirements for lithography's next wave
Proceedings of SPIE (May 23 2004)
Metrology qualification of EUV resists
Proceedings of SPIE (April 15 2010)

Back to Top