Dry ArF lithography

At the heart of dry ArF lithography lies an exposure tool equipped with ArF exciplex laser source (emitting 193-nm wavelength photons). The insertion of ArF (193-nm) lithography into production was originally expected to take place in... 

Figure 13.51 Schematic showing the main physical and optical differences of water immersion and dry ArF lithographies.

Phenyls strongly absorb UV light less than 200 nm because of aromatics. Then alkanes are applied to main chain polymers for ArF lithography (198 nm). Phenyls are superior in dry etching. It is necessary to improve characteristics of dry etching for polymers not containing phenols. The Ohnishi parameter is helpful to indicate characteristics of dry etching it is shown in Equation (2.1). 

---