Directed Self Assembly (DSA) has gained increased momentum in recent years as a cost-effective means for extending lithography to sub-30nm pitch, primarily presenting itself as an alternative to mainstream 193i pitch division approaches such as SADP and SAQP. Towards these goals, IMEC has excelled at understanding and implementing directed self-assembly based on PS-b-PMMA block co-polymers (BCPs) using LiNe flow [1]. These efforts increase the understanding of how block copolymers might be implemented as part of HVM compatible DSA integration schemes. In recent contributions, we have proposed and successfully demonstrated two state-of-the-art CMOS process flows which employed DSA based on the PS-b-PMMA, LiNe flow at IMEC (pitch = 28 nm) to form FinFET arrays via both a ‘cut-last’ and ‘cut-first’ approach [2-4]. Therein, we described the relevant film stacks (hard mask and STI stacks) to achieve robust patterning and pattern transfer into IMEC’s FEOL device film stacks. We also described some of the pattern placement and overlay challenges associated with these two strategies. In this contribution, we will present materials and processes for FinFET patterning and integration towards sub-20 nm pitch technology nodes. This presents a noteworthy challenge for DSA using BCPs as the ultimate resolution for PS-b-PMMA may not achieve such dimensions. The emphasis will continue to be towards patterning approaches, wafer alignment strategies, the effects of DSA processing on wafer alignment and overlay.
Directed Self Assembly (DSA) processes offer the promise of providing alternative ways to extend optical lithography cost-effectively for sub-10nm nodes and present itself as an alternative pitch division approach. As a result, DSA has gained increased momentum in recent years, as a means for extending optical lithography past its current limits. The availability of a DSA processing line can enable to further push the limits of 193nm immersion lithography and overcome some of the critical concerns for EUV lithography.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
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.