A semiconductor device includes an alignment mark. A probe beam is scanned on the alignment mark so as to detect a position coordinate of the alignment mark, and the alignment mark comprises a plurality of bar marks which are arranged in a first predetermined interval along a first direction of scanning the detection beam. Each of the plurality of bar marks comprises a plurality of interconnection marks which are arranged along a second direction orthogonal to the first direction, and a first space between adjacent two of the plurality of interconnection marks is shorter than a wavelength of the detection beam within a range of a design constraint.