Patent ID: 7151981

Claim:
A substrate positioning system adapted to adjust a position of an edge of a substrate relative to a stage that supports the substrate, comprising: a plurality of pushing devices and stops arranged in a spaced relation around a stage that is adapted to support a substrate, wherein each stop occupies a fixed position relative to the stage and each pushing device comprises a movable pusher that is adapted to: extend toward an edge of the substrate that is supported by the stage; contact the edge of the substrate while the substrate is supported by the stage; and continue extending so as to cause the substrate to translate relative to the stage toward one or more of the stops until the substrate contacts the one or more stops; wherein each pushing device further comprises a biasing device coupled to the pusher of the pushing device and adapted to move the pusher toward the edge of the substrate; and wherein each pushing device further comprises a retracting device coupled to the pusher of the pushing device and adapted to counteract the biasing device so as to move the pusher away from the edge of the substrate.