Apparatus and method for containing immersion liquid in immersion lithography

摘要

Immersion liquid is contained in the immersion area located between the last optical member of a projection system and a surface that is the subject of exposure by providing a liquid seal located adjacent to the immersion area. The liquid seal extends between the surface to be exposed and a seal-holding-surface located adjacent to the immersion area. The liquid seal is a seal-forming-liquid that is different from the immersion liquid and that is maintained in place between the surface to be exposed and the seal-holding-surface only by surface tension.