One Paper Will Recount Leti’s Success Reducing Defectivity in Directed Self-Assembly Lithography Technique
In keeping with its mission to develop photolithography alternatives for advanced technology nodes and offer competitive solutions adapted to specific applications, Leti is developing technologies for directed self-assembly lithography (DSA), massively parallel electron beam lithography and nanoimprint lithography.
Leti, a research institute at CEA Tech, will present its latest results in these approaches for fabricating advanced CMOS and silicon photonics devices and sensors in several papers at the SPIE Advanced Lithography conference in San Jose, Calif., Feb. 26-March 2.
The ongoing collaborations with leading industry-equipment companies are designed to offer integrated circuit manufacturers complementary and/or alternative patterning solutions to 193nm immersion lithography and extreme-UV (EUV) technologies. While 193nm immersion technology supports the industry preference for advanced-node developments, it requires a very demanding effort to ensure reliable process controls. EUV’s widespread adoption remains uncertain because its infrastructure still requires significant development and because of questions about its associated cost of ownership.
Leti’s lithography collaborative R&D programs cover three domains:
- IDEAL: directed self-assembly (DSA) lithography
- IMAGINE: massively parallel electron beam lithography
- INSPIRE: nanoimprint lithography
Lithography alternatives hold promise for continued R&D because they may present competitive compromises for the industry. Nanoimprint, DSA and Multi-Beam Lithography: Patterning Technologies with New Integration Challenges.
Stéfan Landis, lead author of the paper
“Massively parallel electron-beam and nano-imprint lithography techniques remain highly attractive because they can provide noteworthy cost-of-ownership benefits. In addition, directed self-assembly lithography shows promising resolution capabilities and appears to be an option to reduce multi-patterning strategies, and the associated high costs for mask-sets.”
A paper with STMicroelectronics and Arkema, “Advanced Surface Affinity Control for DSA Contact Hole Shrink”, focuses on efforts to resolve defectivity, a major challenge for DSA integration. State-of-the-art DSA-related defectivity values remain at least one to two orders of magnitude higher than industrial specifications. The paper recounts Leti’s success at reducing defect density using a DSA graphoepitaxy process flow dedicated to contact hole applications with polystyrene-b-poly(methyl methacrylate) block copolymers.
In addition to its joint papers with partners, Leti will present one invited paper, four oral talks and four posters. It also has been invited to present a poster at LithoVision 2017, which is organized by Nikon. LithoVision is a technical event that precedes the SPIE conference and brings industry experts together to share a global view of lithography trends, challenges, and innovations.