Full Content is available to subscribers

Subscribe/Learn More  >
Proceedings Article

Pupil wavefront manipulation for optical nanolithography

[+] Author Affiliations
Monica Kempsell Sears, Bruce W. Smith

Rochester Institute of Technology (United States)

Joost Bekaert

IMEC (Belgium)

Proc. SPIE 8326, Optical Microlithography XXV, 832611 (February 21, 2012); doi:10.1117/12.917440
Text Size: A A A
From Conference Volume 8326

  • Optical Microlithography XXV
  • Will Conley
  • San Jose, California | February 12, 2012


As semiconductor lithography is pushed to smaller dimensions, process yields tend to suffer due to subwavelength topographical imaging effects. Three dimensional or "thick mask" effects result in such things as a pitch dependent best focus and, for alternating phase shift masks (AltPSMs), an intensity imbalance between etched and un-etched features. Corrective mask structures such as the dual trench AltPSM have been introduced to compensate for such intensity imbalances. In this work, the compensation of thick mask effects is explored using the manipulation of the pupil wavefront through the addition of spherical aberration. The wavefront has been experimentally varied through the manipulation of the lens aberration in a state of the art full field scanner. Results reveal that the influence of spherical aberration on best focus is predictable, allowing focus deviation through pitch to be tuned. Simulations further predict that aberration manipulation can provide compensation for thick mask effects by increasing the useable depth of focus for a particular set of features on both AltPSM and thicker film attenuated PSM masks. Such pupil wavefront correction has the potential to compensate for mask topography by matching thick mask effects to those of thin masks.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Monica Kempsell Sears ; Joost Bekaert and Bruce W. Smith
"Pupil wavefront manipulation for optical nanolithography", Proc. SPIE 8326, Optical Microlithography XXV, 832611 (February 21, 2012); doi:10.1117/12.917440; http://dx.doi.org/10.1117/12.917440

Access This Article
Sign In to Access Full Content
Please Wait... Processing your request... Please Wait.
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).



Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Topic Collections


Buy this article ($18 for members, $25 for non-members).
Sign In