We confirmed the feasibility of a 16-layer write once disc based on Blu-ray Disc optics that was fabricated with
inorganic recording material Bi-Ge-O. The total capacity of the disc achieved 400 GB and 512 GB per single disc side
with BD 1x recording speed utilizing conventional BD technique.
We have succeeded in developing 6-layer write once disc for Blu-ray Disc system with 150 GB capacity per single side disc by use of a novel recording material: germanium oxide doped bismuth peroxide. By optimizing the compositions of the recording films and the layer structure, the jitters of less than 8.0% at the user data recording rate of 72 Mbit/sec were obtained by the application of the write power of less than 16 mW. The write power is low enough to use the commercially available blue laser diodes.
The optical disc with larger capacity and higher speed data recording rate will be required in coming broadband network society. We have developed the inorganic write-once disc with quadruple recording layers for the blu-ray system. We obtained the reflectivity of more than 5% and a jitter value of less than 10% for each recording layer. As a result, we proved the possibility of 100 GB user capacity of 120 mm diameter size.