Line-profile and critical-dimension correlation between a normal-incidence optical CD metrology system and SEM

Weidong Yang; Roger Lowe-Webb; Rahul Korlahalli; Vera Guorong Zhuang; Hiroki Sasano; Wei Liu; David Mui

doi:10.1117/12.473425

16 July 2002 Line-profile and critical-dimension correlation between a normal-incidence optical CD metrology system and SEM

Weidong Yang, Roger Lowe-Webb, Rahul Korlahalli, Vera Guorong Zhuang, Hiroki Sasano, Wei Liu, David Mui

Author Affiliations +

Proceedings Volume 4689, Metrology, Inspection, and Process Control for Microlithography XVI; (2002) https://doi.org/10.1117/12.473425
Event: SPIE's 27th Annual International Symposium on Microlithography, 2002, Santa Clara, California, United States

Abstract

Process tolerances for critical dimensions are becoming increasingly severe as lithographic technology drives the minimum integrated-circuit feature size toward 0.1 micrometers and below. In response, Optical Critical Dimension metrology (OCD), an optical-wavelength light-diffraction technique, is currently undergoing an industry-wide evaluation as a fast, accurate, and non-destructive sub-100nm line-width monitor. As such, effective process monitoring requires detailed understanding of the correlation between CD-SEM and the OCD measurements. Correlation in CD measurements between the OCD technique and SEM techniques is investigated in this paper by measuring photo-resist gratings on a polysilicon gate film stack. Intra-grating CD variation is shown to account for scatter in the correlation plot. A positive offset in the correlation is also observed and a mechanism is proposed to account for the discrepancy. Correlation between CD-SEM and OCD is also demonstrated for samples with three different pitch sizes. A qualitative line-profile correlation between cross-section SEM (X-SEM) and OCD is presented for photoresist gratings in a Focus Exposure Matrix (FEM).

Citation Download Citation

Weidong Yang, Roger Lowe-Webb, Rahul Korlahalli, Vera Guorong Zhuang, Hiroki Sasano, Wei Liu, and David Mui "Line-profile and critical-dimension correlation between a normal-incidence optical CD metrology system and SEM", Proc. SPIE 4689, Metrology, Inspection, and Process Control for Microlithography XVI, (16 July 2002); https://doi.org/10.1117/12.473425

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