Roughness control is a key technical issue in extreme ultraviolet (EUV) lithography. It applies to both line and space (L/S) and contact hole (C/H) structures. Recently, SEMATECH and Tokyo Electron Limited (TEL) developed several track-based techniques, including developer optimization, FIRM™ (Finishing up by Improved Rinse Material), and smoothing to reduce structural roughness. The combination of these techniques improved line width roughness (LWR) about 25% from the 2011 baseline of 32 nm L/S. C/H structures were also tested with the combination process. This paper describes our latest L/S and C/H roughness performance post-lithography and postetch. A feasibility study of negative tone develop (NTD) resists for EUV is also included.

Date Published: 1 April 2013
PDF: 12 pages
Proc. SPIE 8679, Extreme Ultraviolet (EUV) Lithography IV, 867911 (1 April 2013); doi: 10.1117/12.2011566

Published in SPIE Proceedings Vol. 8679:
Extreme Ultraviolet (EUV) Lithography IV
Patrick P. Naulleau, Editor(s)