CD bias reduction in CD-SEM linewidth measurements for advanced lithography

Maki Tanaka; Jeroen Meessen; Chie Shishido; Kenji Watanabe; Ingrid Minnaert-Janssen; Peter Vanoppen

doi:10.1117/12.772088

24 March 2008 CD bias reduction in CD-SEM linewidth measurements for advanced lithography

Maki Tanaka, Jeroen Meessen, Chie Shishido, Kenji Watanabe, Ingrid Minnaert-Janssen, Peter Vanoppen

Proceedings Volume 6922, Metrology, Inspection, and Process Control for Microlithography XXII; 69221T (2008) https://doi.org/10.1117/12.772088
Event: SPIE Advanced Lithography, 2008, San Jose, California, United States

Abstract

The linewidth measurement capability of the model-based library (MBL) matching technique was evaluated experimentally. This technique estimates the dimensions and shape of a target pattern by comparing a measured SEM image profile to a library of simulated line scans. The simulation model uses a non-linear least squares method to estimate pattern geometry parameters. To examine the application of MBL matching in an advanced lithography process, a focus-exposure matrix wafer was prepared with a leading-edge immersion lithography tool. The evaluation used 36 sites with target structures having various linewidths from 45 to 200 nm. The measurement accuracy was evaluated by using an atomic force microscope (AFM) as a reference measurement system. The results of a first trial indicated that two or more solutions could exist in the parameter space in MBL matching. To solve this problem, we obtained a rough estimation of the scale parameter in SEM imaging, based on experimental results, in order to add a constraint in the matching process. As a result, the sensitivity to sidewall variation in MBL matching was improved, and the measurement bias was reduced from 22.1 to 16 nm. These results indicate the possibility of improving the CD measurement capability by applying this tool parameter appropriately.

Citation Download Citation

Maki Tanaka, Jeroen Meessen, Chie Shishido, Kenji Watanabe, Ingrid Minnaert-Janssen, and Peter Vanoppen "CD bias reduction in CD-SEM linewidth measurements for advanced lithography", Proc. SPIE 6922, Metrology, Inspection, and Process Control for Microlithography XXII, 69221T (24 March 2008); https://doi.org/10.1117/12.772088

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