LITHOGRAPHIC EXPOSURE SYSTEM AND ITS METHOD

摘要

PURPOSE: To compensate for errors caused by a change in height of a target. CONSTITUTION: A pattern is exposed by aligning the position by a lithography system, so that a chip larger than a deflection field is formed by exposing a M×N field of a mosaic pattern. This method corrects the deflection field, compensates the direction of the preprocessing pattern on a substrate, and compensates the error based on the height generated by a beam, which lands on a target from the non-vertical direction. The aboved-described two basic procedures are a method called the 'three marks'. This method can be applied only on the field array of 2×2. The 'M×N' method is slightly lacks accurately but includes general situations.