Referring to FIG. 7, a structure 110 including a plurality of openings may be prepared on a jig 210. It was described with reference to FIG. 1 that the structure 110 may be an anodic aluminum oxide (AAO) structure. In addition, a first connection 140 may be formed on a first surface of the structure 110 (an upper surface of the structure in FIG. 7). As illustrated in FIG. 7, the first connection layer 140 may not be formed on one region of the first surface of the structure 110. The first connection layer 140 may be formed by a metal paste screen printing process, or may be formed by a photo-etching process after a metal sputtering process.

Next, as illustrated in FIG. 8, the structure 110 on which the first connection layer 140 is disposed may be turned over and then disposed on the jig 210. Thereafter, a wire 211 may be connected to the first connection layer 140, and an electroplating process may be performed by using the first connection layer 140 as a seed layer. By such an electroplating process, a metal layer 145 contacted to the first connection layer 140 may be formed. The metal layer 145 formed in a lower portion of the opening of the structure 110 may have a thickness in the range of 0.5 to 2 μm.