Phase-shifting and other challenges in optical mask technology

Burn Jeng Lin

doi:10.1117/12.29751

1 March 1991 Phase-shifting and other challenges in optical mask technology

Burn Jeng Lin

Proceedings Volume 1496, 10th Annual Symp on Microlithography; (1991) https://doi.org/10.1117/12.29751
Event: 10th Annual Symposium on Microlithography, 1990, Sunnyvale, CA, United States

Abstract

Optical lithography has benefitted from progresses in wavelength reduction, lenses, resist systems, alignment, focussing, table accuracy, and insute metrology. As a result, the minimum feature size of integrated circuits has been reduced through many generations from 2 micrometers to 0.5 micrometers in manufacturing. There are many opportunities in improving the mask to help continue the progress. The image contrast can be restored by reducing stray light with mask anti-reflection coating at the absorber-air interface. Pre-distorting the mask against the distortion of the imaging lens can drastically improve the overlay performance. Adjusting the gray level or the feature size individually according to the pattern proximity environment can create a larger common exposure-defocus window for different feature shapes. Introducing phase shifts in the mask can simultaneously improve resolution and depth of focus, with the potential of a two-generation improvement with any given projection imaging equipment, provided the overlay capability is upgraded accordingly. In addition to describing and comparing these opportunities, the phase-shifting technology is given a special focus on the working principle, the different approaches to phase shifting, their imaging characteristics in terms of exposure-defocus diagrams, a systems view, and the scope of its development.

Citation Download Citation

Burn Jeng Lin "Phase-shifting and other challenges in optical mask technology", Proc. SPIE 1496, 10th Annual Symp on Microlithography, (1 March 1991); https://doi.org/10.1117/12.29751

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