Patent ID: 7903258
Filing Date: 2011-03-08
Classification: G03F

Abstract:
1. A system for positioning a product, comprising a chuck for supporting the product, an intermediate stage supporting said chuck, and a stationary base supporting said intermediate stage, whereby the chuck can move with respect to the intermediate stage in a first direction X, and the intermediate stage can move with respect to said stationary base in a second direction Y, furthermore comprising at least a first and a second laser interferometer for measuring the position of the chuck relative to the stationary base, a first and a second main part of said respective first and second laser interferometers including optical components for receiving and directing a first and a second laser respectively, the first and second main parts being attached to said intermediate stage and being movable therewith for measuring respectively the distance between a first elongated plane mirror reflector on the chuck that is elongated in the first direction X and an elongated plane mirror reflector on the stationary base that is elongated in the second direction Y, and the distance between a second elongated plane mirror reflector on the chuck that is elongated in the first direction X and the elongated plane mirror reflector on the stationary base.