Patent ID: 6975382
Filing Date: 2005-12-13
Classification: G03B,G03F

Abstract:
1. A projection imaging tool comprising: a reticle that includes a pattern of at least two arrays of alignment attributes, the arrays of alignment attributes having features complementary to each other and the arrays have the same pitch and are offset from each other; a wafer stage that supports a substrate with a recording media; a wafer stage controller that controls the wafer state such that the substrate is located in a first position and the reticle pattern is exposed onto the substrate recording media, the controller then commands the wafer stage so as to shift the substrate to a second position and the reticle pattern is exposed such that it overlaps the reticle pattern in the first position and is shifted in a direction perpendicular to a scanning direction by an amount that corresponds to the array offset, the controller then commands the wafer stage to rotate the substrate a desired angular amount and the reticle pattern is exposed onto the substrate in a third position, wherein the reticle pattern in the third position overlaps the reticle pattern in the first position; a processor that determines a scanning lens distortion map from positional offsets of the alignment attributes of the overlapped exposed patterns on the substrate.