OVERLAY MARK OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: An overlay mark of a semiconductor device is provided to measure easily an overlay mark by preventing an asymmetric shape of a vernier due to a variation of surrounding pattern density. CONSTITUTION: An amin scale of a regular quadrilateral shape is formed on a semiconductor substrate(10). A vernier of a regular quadrilateral shape is formed on an inner side of the amin scale. A blank pattern(20) is formed on an outer side of the amin scale. The blank pattern(20) has the same layer as the amin scale and the vernier. The blank pattern(20) is formed by removing a pattern of a predetermined width of the outer side of the amin scale. An overlay mark(16) is surrounded by the blank pattern(20). The blank pattern(20) is used for preventing the asymmetric vernier formed by a variation of surrounding pattern density.