Research on microstructure of optical disc and its master disc for long-life holographic storage

In this work, we report the influence of laser intensity, via laser direct writing focus on a photoresist, on the different dimensions of the microstructure. A series of laser intensities (30mW, 30%, 35%, 40%, 45%, 50%, 55%) are conducted and the reaction mechanism between laser and photoresist is also proposed. The microstructure size increased with laser intensity and the optimum laser intensity is found to be 45% for both 2μm and 4μm microstructure. The micropore size remains the same size during the whole process (master disc-nickel disc-son disc) indicating the excellent stability and reliability of the process. Additionally, the demolding process during the production of son disc is smooth due to the controlled angle between Ni base surface and photoresist. This work proves the feasibility and compatibility of the production of a new physical format for long-life holographic storage disc, which significantly increase the storage density, access speed and shelf life compared to traditional disc, by applying traditional processing method (master disc-Ni discson disc).