Patent ID: 8634055

Claim:
An immersion liquid confinement apparatus for confining 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 recovering the immersion liquid from the immersion area, the apparatus comprising: a confinement member that includes an outlet and an aperture through which a patterned image is projected onto the object; a first liquid-permeable member covering the outlet and having a first surface that faces the object and a second surface opposite the first surface, the second surface contacting a first chamber, the immersion liquid being recovered from the immersion area into the first chamber through the first liquid-permeable member; a second liquid-permeable member disposed adjacent to and spaced from the second surface of the first liquid-permeable member, the second liquid-permeable member having a first surface that faces the second surface of the first liquid-permeable member and a second surface opposite the first surface of the second liquid-permeable member, the second surface of the second liquid-permeable member contacting a second chamber that is different from the first chamber, the immersion liquid recovered from the immersion area into the first chamber through the first liquid-permeable member being collected into the second chamber through the second liquid-permeable member; and an entrance port of the first chamber through which the first chamber is communicated with a vacuum system, a hydrophobic porous member covering the entrance port.