An optimum design of replication process to improve optical and geometrical properties in DVD-RAM substrates

The purpose of the experiment was to find the optimum replication process f or making submicron structured DVD-RAM substrates with superb optical and g eometrical properties. The optimum processing conditions were presented. It was found that the birefrigence, which is regarded as one of the most impo rtant optical properties for an optical disk, was very sensitive to the mol d wall temperature history. Also, the integrity of the replication, represe nted by the land-groove structure, and the radial tilt were influenced most by the mold temperature and the compression pressure.