Modeling the EUV multilayer deposition process on EUV blanks

Abstract

Extreme ultraviolet lithography (EUVL) is the leading next generation lithography (NGL) technology to succeed optical lithography at the 22 nm node and beyond. EUVL requires a low defect density reflective mask blank, which is considered to be the most critical technology gap for commercialization of the technology. At the SEMATECH Mask Blank Development Center (MBDC), research on defect reduction of EUV mask blanks is being pursued using the Veeco Nexus deposition tool. Its defect performance is one of the factors limiting the availability of defect-free EUVL mask blanks. SEMATECH has identified better understanding of the physics of the deposition process as one of the keys to improving the defect performance of Nexus tools. SEMATECH is therefore undertaking an effort to model the physics of the tool backed with an experimental program to characterize the process. The goal is to be able to predict defect performance and defect improvement to direct new tool design. In this paper, we present the results of simulating the deposition rate and uniformity of deposited multilayers and growth of the multilayer on a given defect profile.