Abstract: A photomask structure includes a plurality of first layout patterns, a plurality of second layout patterns, and a ring-shaped layout pattern. The first layout patterns and the second layout patterns are alternately arranged. Each of the first layout patterns has a first end and a second end. Each of the second layout patterns has a third end and a fourth end. The first end is adjacent to the third end. The second end is adjacent to the fourth end. The ring-shaped layout pattern surrounds the first layout patterns and the second layout patterns. The first end is connected to the ring-shaped layout pattern. The second end is not connected to the ring-shaped layout pattern. The third end is not connected to the ring-shaped layout pattern. The fourth end is connected to the ring-shaped layout pattern.

Abstract: A self-aligned multiple patterning mark is provided. The mark includes a group of patterns disposed on the substrate and a cover layer. The group of patterns includes a plurality of strip patterns extending in a first direction and arranged parallel to each other, and the ends of two adjacent strip patterns are connected to each other to form an independent ring. The cover layer is disposed on the substrate and covers the group of patterns. The cover layer has an opening extending in a second direction across the first direction, and the cover layer covers two opposite ends of each strip pattern.

Abstract: A monitoring structure for a critical dimension of a lithography process including a dummy pattern layer and a patterned photoresist layer is provided. The dummy pattern layer includes a dummy pattern. The patterned photoresist layer includes at least one monitoring mark located above the dummy pattern. The monitoring mark includes a first portion and a second portion that intersect each other. The first portion extends in a first direction, the second portion extends in a second direction, and the first direction intersects the second direction.

Abstract: A monitoring structure for a critical dimension of a lithography process including a dummy pattern layer and a patterned photoresist layer is provided. The dummy pattern layer includes a dummy pattern. The patterned photoresist layer includes at least one monitoring mark located above the dummy pattern. The monitoring mark includes a first portion and a second portion that intersect each other. The first portion extends in a first direction, the second portion extends in a second direction, and the first direction intersects the second direction.