An apparatus for immersion lithography that includes an imaging lens which has a front surface, a fluid-containing wafer stage for supporting a wafer that has a top surface to be exposed positioned spaced-apart and juxtaposed to the front surface of the imaging lens, and a fluid that has a refractive index between about 1.0 and about 2.0 filling a gap formed in-between the front surface of the imaging lens and the top surface of the wafer. A method for immersion lithography can be carried out by flowing a fluid through a gap formed in-between the front surface of an imaging lens and a top surface of a wafer. The flow rate and temperature of the fluid can be controlled while particulate contaminants are filtered out by a filtering device.