Reduction of line width and edge roughness by resist reflow process for extreme ultra-violet lithography

In Wook Cho; Joon-Min Park; Hyunsu Kim; Joo-Yoo Hong; Seong-Sue Kim; Han-Ku Cho; Hye-Keun Oh

doi:10.1117/12.814108

1 April 2009 Reduction of line width and edge roughness by resist reflow process for extreme ultra-violet lithography

In Wook Cho, Joon-Min Park, Hyunsu Kim, Joo-Yoo Hong, Seong-Sue Kim, Han-Ku Cho, Hye-Keun Oh

Proceedings Volume 7273, Advances in Resist Materials and Processing Technology XXVI; 72732D (2009) https://doi.org/10.1117/12.814108
Event: SPIE Advanced Lithography, 2009, San Jose, California, United States

Abstract

Extreme ultra-violet lithography (EUVL) has been prepared for next generation lithography for several years. We could get sub-22 nm line and space (L/S) pattern using EUVL, but there are still some problems such as roughness, sensitivity, and resolution. According to 2007 ITRS roadmap, line edge roughness (LER) has to be below 1.9 nm to get a 22 nm node, but it is too difficult to control line width roughness (LWR) because line width is determined by not only the post exposure bake (PEB) time, temperature and acid diffusion length, but also the component and size of the resist. A new method is suggested to reduce the roughness. The surface roughness can be smoothed by applying the resist reflow process (RRP) for the developed resist. We made resist profile which has surface roughness by applying exposure, PEB and development process for line and space pattern. The surface roughness is calculated by changing parameters such as the protected ratio of resin. The PEB time is also varied. We compared difference between 1:1 L/S and 1:3 L/S pattern for 22 nm. Developed resist baked above the glass transition temperature will flow and the surface will be smoothed. As a result, LER and LWR will be much smaller after RRP. The result shows that the decreasing ratio of LER due to RRP is larger when initial LER is large. We believe that current ~ 5 nm LWR can be smoothed to ~ 1 nm by using RRP after develop.

Citation Download Citation

In Wook Cho, Joon-Min Park, Hyunsu Kim, Joo-Yoo Hong, Seong-Sue Kim, Han-Ku Cho, and Hye-Keun Oh "Reduction of line width and edge roughness by resist reflow process for extreme ultra-violet lithography", Proc. SPIE 7273, Advances in Resist Materials and Processing Technology XXVI, 72732D (1 April 2009); https://doi.org/10.1117/12.814108

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