摘要 |
A semiconductor structure and a method of determining an overlay error produced during formation of the semiconductor structure are disclosed. The semiconductor structure comprises a first two-dimensional periodic pattern and a second two-dimensional periodic pattern, which overlap with each other, wherein a relative position between the overlapping first and second two-dimensional periodic patterns indicates the magnitude and direction of an overlay error caused during the formation of the first and second two-dimensional periodic patterns. The semiconductor allows one to independently determine the overlay errors in linearly independent directions by directing a light beam of known optical properties onto the first and second two-dimensional periodic patterns and by analyzing the diffracted beam by comparison with reference data.
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