Differential signal scatterometry overlay metrology: an accuracy investigation

Daniel Kandel; Mike Adel; Berta Dinu; Boris Golovanevsky; Pavel Izikson; Vladimir Levinski; Irina Vakshtein; Philippe Leray; Mauro Vasconi; Bartlomiej Salski

doi:10.1117/12.725929

18 June 2007 Differential signal scatterometry overlay metrology: an accuracy investigation

Daniel Kandel, Mike Adel, Berta Dinu, Boris Golovanevsky, Pavel Izikson, Vladimir Levinski, Irina Vakshtein, Philippe Leray, Mauro Vasconi, Bartlomiej Salski

Author Affiliations +

Proceedings Volume 6616, Optical Measurement Systems for Industrial Inspection V; 66160H (2007) https://doi.org/10.1117/12.725929
Event: Optical Metrology, 2007, Munich, Germany

Abstract

The overlay control budget for the 32nm technology node will be 5.7nm according to the ITRS. The overlay metrology budget is typically 1/10 of the overlay control budget resulting in overlay metrology total measurement uncertainty (TMU) requirements of 0.57nm for the most challenging use cases of the 32nm node. The current state of the art imaging overlay metrology technology does not meet this strict requirement, and further technology development is required to bring it to this level. In this work we present results of a study of an alternative technology for overlay metrology - Differential signal scatterometry overlay (SCOL). Theoretical considerations show that overlay technology based on differential signal scatterometry has inherent advantages, which will allow it to achieve the 32nm technology node requirements and go beyond it. We present results of simulations of the expected accuracy associated with a variety of scatterometry overlay target designs. We also present our first experimental results of scatterometry overlay measurements, comparing this technology with the standard imaging overlay metrology technology. In particular, we present performance results (precision and tool induced shift) and address the issue of accuracy of scatterometry overlay. We show that with the appropriate target design and algorithms scatterometry overlay achieves the accuracy required for future technology nodes.

Citation Download Citation

Daniel Kandel, Mike Adel, Berta Dinu, Boris Golovanevsky, Pavel Izikson, Vladimir Levinski, Irina Vakshtein, Philippe Leray, Mauro Vasconi, and Bartlomiej Salski "Differential signal scatterometry overlay metrology: an accuracy investigation", Proc. SPIE 6616, Optical Measurement Systems for Industrial Inspection V, 66160H (18 June 2007); https://doi.org/10.1117/12.725929

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available