Special Section on Dimensional Metrology with Atomic Force Microscopy: Instruments and Applications

Sidewall slope sensitivity of critical dimension atomic force microscopy

[+] Author Affiliations
Aaron Cordes, Benjamin Bunday

SEMATECH, 257 Fuller Road, Suite 2200, Albany, New York, 12203

Eric Cotrell

Bruker AFM Metrology Group, 112 Robin Hill Road, Santa Barbara, California, 93117

J. Micro/Nanolith. MEMS MOEMS. 11(1), 011011 (Feb 24, 2012). doi:10.1117/1.JMM.11.1.011011
History: Received August 18, 2011; Revised October 24, 2011; Accepted November 1, 2011
Text Size: A A A

Abstract.  Critical dimension atomic force microscopy is employed in semiconductor manufacturing as a reference system, used to provide accurate information to calibrate other tools. However, faced with increasingly challenging features, operators of these systems have needed to use multiple specialized tip types and scan modes on a sample in order to acquire a complete data set. To overcome this need, we measure the potential biases introduced within such a hybrid data set with respect to sidewall slope angle. Measurement results are presented for features with varying sidewall slope across a range of angles just above and below 90 deg. This sample was scanned with a variety tips and two different scan modes: critical dimension (CD) mode, an adaptive sidewall scanning mode able to detect limited undercut; and deep trench (DT) mode, a dynamic top-down-only mode commonly employed on small, challenging measurement features. In DT mode, we detected a cutoff point at 89 deg, below which all tips track the surface with a size-dependent bias. In contrast, CD mode produced results that were much more invariant to tip size except for the smallest tips. The smallest tips in CD mode exhibited divergent behavior, compared to both the mid-range CD tips and one another.

Figures in this Article
© 2012 Society of Photo-Optical Instrumentation Engineers

Citation

Aaron Cordes ; Benjamin Bunday and Eric Cotrell
"Sidewall slope sensitivity of critical dimension atomic force microscopy", J. Micro/Nanolith. MEMS MOEMS. 11(1), 011011 (Feb 24, 2012). ; http://dx.doi.org/10.1117/1.JMM.11.1.011011


Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).

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

PubMed Articles
Advertisement
  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.