摘要 |
Shot regions on a wafer are exposed and a first reticle pattern image is transferred thereon, and an LSA mark is formed in the center of each shot region of a chip positioned centrosymmetrically with respect to the center of the wafer. The wafer is prealigned, a rotation is corrected, and the position of the LSA mark is measured. The error parameter is produced by means of least squares method based on designed values and measured values to produce a new chip arrangement map, based on which the second and on reticle patterns are transferred by exposure. Thus, an offset correction fault with the rotation component of the reticle pattern is eliminated, thereby increasing throughput.
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