Feasibility study of manufacturing process and quality control for the new alternating PSM structure

Abstract

Alternating phase-shifting mask (Alt.PSM) technology is the most effective approach to expand resolution limitation and expand the process window of lithography. Currently, etched quartz Alt.PSMs have been introduced not only for device development but also for production use. We have been supplying Alt.PSMs with Single trench + Undercut structures for the mass-production of KrF lithography and reported this structure is applicable for ArF lithography. On the other hand, we have introduced preliminary manufacturing results of the new Alt.PSM structure. This structure has the advantages, which are exempted from biasing issues and narrow chrome width limitations. In order to make sure the adaptability of this new Alt.PSM structure in mass-manufacturing, we started to investigate productivity for this structure. In this paper, we will discuss about the feasibility study of manufacturing process and quality control which include CD performance results, alignment error tolerance evaluations and defect assurance evaluations.