New method of tilted illumination using grating mask: advanced tilted illumination on mask

Hoyoung Kang; Chul Hong Kim; Woo-Sung Han; Young-Bum Koh; Moon-Yong Lee

doi:10.1117/12.150427

8 August 1993 New method of tilted illumination using grating mask: advanced tilted illumination on mask

Hoyoung Kang, Chul Hong Kim, Woo-Sung Han, Young-Bum Koh, Moon-Yong Lee

Proceedings Volume 1927, Optical/Laser Microlithography; (1993) https://doi.org/10.1117/12.150427
Event: SPIE'S 1993 Symposium on Microlithography, 1993, San Jose, CA, United States

Abstract

A modified illumination method recently developed is known to improve resolution and depth of focus (DOF) dramatically. But, it requires substantial modification in the optical projection system and has some problems such as low throughput caused by low intensity and poor uniformity. To solve these problems, we developed a new illumination technique, named advanced tilted illumination on mask (ATOM) using phase grating which is the same, in principle, as quadrupole illumination but a very simple approach with little loss of intensity. In our experiments, we obtained the best resolution of 0.28 micrometers and 2.0 micrometers DOF for 0.36 micrometers feature size with an i-line stepper, which is two times as wide as that of a conventional illumination method. We also obtained 0.22 micrometers resolution and 2.0 micrometers DOF for 0.28 micrometers with an 0.45 NA KrF excimer laser stepper. For complex device patterns, a more than 1.5 times wider DOF could be obtained compared to the conventional illumination method. From these results, we conclude that second generation of 64 M DRAM with 0.30 micrometers design rule could be printed well with this technology combined with high NA (> 0.5) i-line steppers. With a KrF excimer laser stepper, a 256 M DRAM with a 0.25 micrometers design rule can be printed with the wide DOF.

Citation Download Citation

Hoyoung Kang, Chul Hong Kim, Woo-Sung Han, Young-Bum Koh, and Moon-Yong Lee "New method of tilted illumination using grating mask: advanced tilted illumination on mask", Proc. SPIE 1927, Optical/Laser Microlithography, (8 August 1993); https://doi.org/10.1117/12.150427

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