Patent ID: 7782445
Filing Date: 2010-08-24
Classification: G03D,G03F,H01L

Abstract:
1. A wafer chuck assembly, comprising: a first chuck section configured to hold a semiconductor wafer on a support surface thereof; a second chuck section removably attached to the first chuck section; the first chuck section having a gap therein, the gap located adjacent an outer edge of the wafer, and the gap containing a volume of immersion lithography fluid therein; a fluid circulation path configured within the first chuck section so as to facilitate the radial outward movement of the immersion lithography fluid in the gap, thereby maintaining a meniscus of the immersion lithography fluid at a selected height with respect to a top surface of the semiconductor wafer; wherein the fluid circulation path further comprises an inlet path through which pressurized fluid is introduced, and in communication with the immersion lithography fluid in the gap, and a return path through which excess immersion lithography fluid from the gap is removed therefrom; a first fluid column, defined by the gap; a second fluid column formed within the first chuck section, disposed radially outward with respect to the first fluid column; the second fluid column including the inlet path and the return path passing therethrough; and a passage configured within the second chuck section, the passage fluidly connecting the first and the second fluid columns; wherein the meniscus of the immersion lithography fluid is passively controlled through fluid level control within the second fluid column.