The MEEF NILS divergence for low k1 lithography

Richard Schenker; Wen-hao Cheng; Gary Allen

doi:10.1117/12.742273

30 October 2007 The MEEF NILS divergence for low k1 lithography

Richard Schenker, Wen-hao Cheng, Gary Allen

Proceedings Volume 6730, Photomask Technology 2007; 67301M (2007) https://doi.org/10.1117/12.742273
Event: SPIE Photomask Technology, 2007, Monterey, California, United States

Abstract

For tight pitch patterning with sub-wavelength mask features, simulations and wafer data show that many mask stacks that provide superior image contrast, can provide inferior MEEF performance. For example, 6% MoSi EPSM is found to have higher MEEF than binary masks despite having better contrast and exposure latitude when equal lines and spaces on the mask are used to pattern equal lines and spaces on the wafer. Likewise, the deposition of SiO₂ on-top of the chrome surface of a binary mask improves contrast but degrades MEEF compared to a binary mask. When contrast is varied by mask stack or by print bias, MEEF is poorly correlated with contrast and often increases with increasing contrast. The optimal print bias for exposure latitude is significantly different than the optimum print bias for MEEF. MEEF, on the other hand, is highly correlated with the difference between maximum and minimum intensity when one varies mask stack, print bias and illumination. Analytical MEEF equations are derived that support this strong relationship between MEEF and the difference between maximum and minimum intensity.

Citation Download Citation

Richard Schenker, Wen-hao Cheng, and Gary Allen "The MEEF NILS divergence for low k1 lithography", Proc. SPIE 6730, Photomask Technology 2007, 67301M (30 October 2007); https://doi.org/10.1117/12.742273

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