High-resolution profilometry for improved overlay measurements of CMP-processed layers

Anna Mathai; Jason Schneir

doi:10.1117/12.308725

8 June 1998 High-resolution profilometry for improved overlay measurements of CMP-processed layers

Anna Mathai, Jason Schneir

Proceedings Volume 3332, Metrology, Inspection, and Process Control for Microlithography XII; (1998) https://doi.org/10.1117/12.308725
Event: 23rd Annual International Symposium on Microlithography, 1998, Santa Clara, CA, United States

Abstract

Chemical-mechanical polishing (CMP) processes are widely used in the semiconductor industry to enable multilevel device processing and smaller device features with smaller stepper lens depth of focus. However, CMP planarization of the wafers can lead to failure modes in stepper alignment and overlay measurements that rely on some topography for contrast. It is also been speculated that the CMP process, with its rotating pads that are wetted with polishing slurry, has a spreading or smearing effect on the overlay targets. Both these effects can lead to inaccurate and imprecise overlay measurements. In this paper, we present the results of measuring the depth and asymmetry of overlay targets post-CMP using a High Resolution Profiler. We find clear evidence of smearing in post-CMP overlay targets and discuss its impact on stepper registration error.

Citation Download Citation

Anna Mathai and Jason Schneir "High-resolution profilometry for improved overlay measurements of CMP-processed layers", Proc. SPIE 3332, Metrology, Inspection, and Process Control for Microlithography XII, (8 June 1998); https://doi.org/10.1117/12.308725

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