摘要 |
An immersion liquid confinement apparatus confines an immersion liquid in an immersion area that includes a gap between a projection system and an object of exposure in an immersion lithography system. The apparatus also recovers the immersion liquid from the immersion area. The apparatus includes an aperture through which a patterned image is projected, an outlet, a first chamber into which the immersion liquid is recovered through the outlet, and a second chamber into which the immersion liquid is recovered through a porous member from the first chamber. The porous member has a first surface contacting the first chamber and a second surface contacting the second chamber. A vertical position of a first portion of the first surface is different from a vertical position of a second portion of the first surface. |