Nanoimprint lithography steppers for volume fabrication of leading-edge semiconductor integrated circuits

• Published in: Microsystems & nanoengineering Vol. 3; no. 1; p. 17075
• Main Author: Sreenivasan, S.V.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 25.09.2017; Springer Nature B.V; Nature Publishing Group
• Subjects: 639/925; 639/925/927/1007; Contamination; Disruption; Engineering; Infrastructure; Integrated circuits; Lithography; Nanopatterning; Nanotechnology; Photolithography; Process engineering; Reinforcement; Review; review-article; Risk; Scaling; steppers; nanoscale overlay; precision systems; semiconductor fabrication; UV nanoimprint; jet and flash imprint; nanoimprint defectivity
• ISSN: 2055-7434; 2096-1030; 2055-7434
• DOI: 10.1038/micronano.2017.75

This article discusses the transition of a form of nanoimprint lithography technology, known as Jet and Flash Imprint Lithography (J-FIL), from research to a commercial fabrication infrastructure for leading-edge semiconductor integrated circuits (ICs). Leading-edge semiconductor lithography has some of the most aggressive technology requirements, and has been a key driver in the 50-year history of semiconductor scaling. Introducing a new, disruptive capability into this arena is therefore a case study in a “high-risk-high-reward” opportunity. This article first discusses relevant literature in nanopatterning including advanced lithography options that have been explored by the IC fabrication industry, novel research ideas being explored, and literature in nanoimprint lithography. The article then focuses on the J-FIL process, and the interdisciplinary nature of risk, involving nanoscale precision systems, mechanics, materials, material delivery systems, contamination control, and process engineering. Next, the article discusses the strategic decisions that were made in the early phases of the project including: (i) choosing a step and repeat process approach; (ii) identifying the first target IC market for J-FIL; (iii) defining the product scope and the appropriate collaborations to share the risk-reward landscape; and (iv) properly leveraging existing infrastructure, including minimizing disruption to the widely accepted practices in photolithography. Finally, the paper discusses the commercial J-FIL stepper system and associated infrastructure, and the resulting advances in the key lithographic process metrics such as critical dimension control, overlay, throughput, process defects, and electrical yield over the past 5 years. This article concludes with the current state of the art in J-FIL technology for IC fabrication, including description of the high volume manufacturing stepper tools created for advanced memory manufacturing. Nanomanufacturing: A step closer to nanoimprint based integrated–circuit fabrication An appraisal of sub-40nm half-pitch lithography technologies for high-volume manufacture of semiconductor integrated circuits is provided. Although cutting-edge semiconductor lithography has been an important driver for the electronics industry, only a small subset of researched nanolithography techniques have been explored for mass production in semiconductor integrated circuits fabrication facilities. By assessing the evolution of a nanoimprint technique known as jet and flash imprint lithography (J-FIL) stepper technology, S. V. Sreenivasan at the University of Texas at Austin, United States, has identified the main characteristics for insertion of J-FIL for fabrication of semiconductor memory with sub-20nm half-pitch structures. The demonstrated ability of nanoimprint to pattern resist structures of less than 5 nanometers makes it an attractive choice for potentially extending the scaling roadmap for high volume semiconductor manufacturing.