Write-once optical data storage media with large reflectance change with metal-island films

Gold (Au), silver (Ag), copper (Cu), and aluminum (Al) island films have been investigated for write-once optical data storage media with the high reflectance and the large reflectance changes induced by laser irradiation. We show that, of the four, the Ag and the Cu island films are the most useful as WO media at 800 nm. The Al island films are useful for a shorter wavelength region. The optical and structural changes in laser-written regions on the island films have also been investigated experimentally. It appears that the metal-island films show great potential as optical data storage media for compact-disk-compatible write-once optical disks.