Recently the portable device called MINion for single molecule analysis was developed by Oxford Nanopore Technology. The electrical detection technique for the solid state device was utilized for single molecule detection . However, the large error rates were reported by several journals, even though the significant error reduction was developed after the invention of the portable nanopore device. In this report, we introduce the optical nanopore fabrication by using plasmonic optical enhancement effect. First, the Au thin films were vacuum-deposited on the nanometer thin SiN film, followed by removal of SiN film and by drilling Au apertures by using focused ion beam (FIB) technique. Then, electron beam irradiations on the specimens either by using low energy field emission electron beam microscopy (FESEM) or high energy Transmission electron beam microscopy (TEM). In addition, the periodic grooves, or the periodic Au aperture array were fabricated on the Au sample in order to provide strong plamonic optical enhancements. During the electron irradiation on the fabricated Au surface, we observed the diffused binary Au-C membrane due to Ostwald ripening and also the unstable Au-C mixed phase change via spinodal decomposition. We also found that the Au cluster diffusion would depend upon the electron beam fluence. However, the exact understanding of this phenomenon is still on-going investigation.