OCD metrology by floating n/k

Shinn-Sheng Yu; Jacky Huang; Chih-Ming Ke; Tsai-Sheng Gau; Burn J. Lin; Anthony Yen; Lawrence Lane; Vi Vuong; Yan Chen

doi:10.1117/12.713341

5 April 2007 OCD metrology by floating n/k

Shinn-Sheng Yu, Jacky Huang, Chih-Ming Ke, Tsai-Sheng Gau, Burn J. Lin, Anthony Yen, Lawrence Lane, Vi Vuong, Yan Chen

Proceedings Volume 6518, Metrology, Inspection, and Process Control for Microlithography XXI; 65183C (2007) https://doi.org/10.1117/12.713341
Event: SPIE Advanced Lithography, 2007, San Jose, California, United States

Abstract

In this paper, one of the major contributions to the OCD metrology error, resulting from within-wafer variation of the refractive index/extinction coefficient (n/k) of the substrate, is identified and quantified. To meet the required metrology accuracy for the 65-nm node and beyond, it is suggested that n/k should be floating when performing the regression for OCD modeling. A feasible way of performing such regression is proposed and verified. As shown in the presented example, the measured CDU (3σ) with n/k fixed and n/k floating is 1.94 nm and 1.42 nm, respectively. That is, the metrology error of CDU committed by assuming n/k fixed is more than 35% of the total CDU.

Citation Download Citation

Shinn-Sheng Yu, Jacky Huang, Chih-Ming Ke, Tsai-Sheng Gau, Burn J. Lin, Anthony Yen, Lawrence Lane, Vi Vuong, and Yan Chen "OCD metrology by floating n/k", Proc. SPIE 6518, Metrology, Inspection, and Process Control for Microlithography XXI, 65183C (5 April 2007); https://doi.org/10.1117/12.713341

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