High-throughput Screening of Extreme Ultraviolet Photoresists using Molecular Layer Deposition

with Dr. David Bergsman
University of Washington

ABSTRACT: Extreme ultraviolet (EUV) photolithography has seen substantial interest from the semiconductor industry as a tool to create sub-10 nm features, which are necessary to improve device performance. However, EUV lithography will require new photoresist materials that absorb this light efficiently, maintain structural integrity under high-energy exposure, and are sufficiently thin to avoid pattern collapse. In this presentation, I will highlight the Bergsman Group’s work to study the stability and mechanical properties of organic-inorganic hybrid thin films deposited by molecular layer deposition (MLD), for use in EUV photolithography applications. MLD is a vapor-phase layer-by-layer thin film deposition process that can create films with subnanometer thickness and compositional control. Using our previously published high-throughput multi-chamber MLD system, we synthesized and screened 18 different film chemistries using combinations of three inorganic elements—zinc, aluminum, and tin—and six organic precursors. These films were evaluated for stability in air, developer compatibility, and etchant resistance, both before and after UV and e-beam exposure. Selected high-performing materials were patterned using an e-beam source. Our findings reveal that specific combinations of organic and inorganic components yield films with significantly improved properties and stability in potential developers.

BIOGRAPHY: Prof. Bergsman is an assistant professor in the Department of Chemical Engineering at the University of Washington (UW). He received his B.S. in Chemical Engineering from UW in 2012 and his Ph.D. from Stanford University in 2018. His research group uses atomic layer processing to address challenges in nanotechnology and sustainability. Among his many awards, he is the recipient of the ACS PRF New Investigator Award, American Vacuum Society (AVS) Thin Film Division Paul H. Holloway Young Investigator Award, and the Pacific Northwest AVS Emerging Leader Award.

With refreshments from Panera Bread