With reference to FIG. 5, the second member 36 may include a first area as an inner area of the second member 36, and a second area C extending along and at an outer edge of each of at least three sides of the second member 36. A vertical dimension, a thickness, or a shape of the first area may be different from that of the second area C.

The second area C may extend along and at a left outer edge, an upper outer edge and a right outer edge of the second member 36. One side (or one end) of the target size A to be achieved by irradiating the laser beam, for example, the cutting line CL may be disposed in the second area C of the second member 36. A width of the second area C may be determined based on a process tolerance of an area to which the laser beam of the laser apparatus L is irradiated.

In the second area C, the second member 36 may be formed to be recessed inwardly from the bottom (or lower) surface of the second member 36. For example, the second area C may include a step area ST.

With reference to FIG. 6, a thickness of the second member 36 may have a value of T1 in the first area, and a value of T2 in the second area C. The value of T1 may be greater than the value of T2. A depth or a vertical dimension of the step may be equal to a d1 value which is a difference between the T1 value and the T2 value.