Improvement of inter-field CDU by using on-product focus control

Kyeong Dong Park; Tony Park; Jong Hyun Hwang; Jin Phil Choi; Young Seog Kang

doi:10.1117/12.2046224

2 April 2014 Improvement of inter-field CDU by using on-product focus control

Kyeong Dong Park, Tony Park, Jong Hyun Hwang, Jin Phil Choi, Young Seog Kang

Proceedings Volume 9050, Metrology, Inspection, and Process Control for Microlithography XXVIII; 90500R (2014) https://doi.org/10.1117/12.2046224
Event: SPIE Advanced Lithography, 2014, San Jose, California, United States

Abstract

This paper introduces to improve inter-field CDU with on-product focus control by diffraction based focus (DBF) method. For DBF target selection, a robust focus metrology for focus control was obtained, and the selected DBF target was integrated on each seven spot of a product reticle. For on-product focus control, previously on-product focus monitoring was performed, and the monitored lots showed a stable focus fingerprint. Based on the result, Z and Z/ Rx/Ry corrections per field on wafers were applied. Focus uniformity of controlled wafers was improved up to 29% in comparison with non-corrected ones. To demonstrate the improvement of inter-field CDU, Full CDs on wafers were measured by SEM. As a result, inter-field CDU for controlled wafers was improved by 16% (3σ) compared with noncontrolled wafers.

Citation Download Citation

Kyeong Dong Park, Tony Park, Jong Hyun Hwang, Jin Phil Choi, and Young Seog Kang "Improvement of inter-field CDU by using on-product focus control", Proc. SPIE 9050, Metrology, Inspection, and Process Control for Microlithography XXVIII, 90500R (2 April 2014); https://doi.org/10.1117/12.2046224

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