Translator Disclaimer
3 March 2010 Comparative study of resolution limits for double patterning and EUV processes for the 32nm contact hole case
Author Affiliations +
Currently, EUV and double patterning (DP) are competing technologies for the 22nm hp node. The goal of this paper is to perform a case study and explore resolution limits on a 32nm contact hole array. In order to investigate the resolution limit for a DP process quantitatively, considering the substrate topography structure is crucial. We applied wafertopography/ lithography simulation to study the relevant effects in detail. To perform a comparative study between ArF DP and EUV lithography we first analyzed the resolution limit for DP process. We investigated the performance of a LDLD and a LFLE (litho-freeze-litho-etch) process by decreasing pitch until the resolution limit was reached. The possible minimum x- pitch (with y-parallel line, first mask) is 85nm, the minimum y-pitch generated for the second litho step with x-parallel lines is 90nm. This x-y anisotropic phenomenon is caused by the second litho step, where oblique incident light propagating through space regions contributes to total image. The bulk image distribution is sensitive to the material in the spacer region, therefore further process optimization is possible by tuning material properties. Alternatively the fabrication of 32nm size contact holes with EUV lithography was simulated. Pattern shift due to shadowing, aberrations and flare effects have been considered. A pitch of 64nm (1:1) can be realized at low flare levels, but corrections for shadowing and flare are essential. Based on this quantification the gap of possible minimum pitch between DP and EUV are discussed. Furthermore relation between DP topography effect and SMO are discussed.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Itaru Kamohara, Keiichi Tajima, and Thomas Schmoeller "Comparative study of resolution limits for double patterning and EUV processes for the 32nm contact hole case", Proc. SPIE 7640, Optical Microlithography XXIII, 76400D (3 March 2010);

Back to Top