IMMERSION FLOW FIELD MAINTENANCE SYSTEM FOR IMMERSION LITHOGRAPHY MACHINE

摘要

An immersion flow field maintenance system is used in an immersion lithography machine which includes a projection objective lens, at least a wafer stage for supporting a wafer, and an immersion supplying system distributed around the projection objective lens for producing an immersion flow field under the projection objective lens. The immersion flow field maintenance system includes a horizontal guideway, a flat board connected with the horizontal guideway through the cantilever, and plural drivers for driving the flat board to move. When the wafer is unloaded and the wafer stage is moved out of the exposure area under the projection objective lens, the flat board connects to and moves synchronously with the wafer stage to transfer the immersion flow field from above the wafer stage to above the flat board. When the wafer is loaded and the wafer stage is moved into the exposure area, the flat board connects to and moves synchronously with the wafer stage to transfer the immersion flow field from above the flat board to above the wafer stage.