High density rewritable media for near-field optical recording

High density rewritable media for near-field recording are fabricated and their writing and readout characteristics are examined. High density substrates for rewritable media are prepared using a phase transition mastering technique to overcome the limitation of the deep UV laser recorder. A cover-layer with a UV curable material is coated on the rewritable media and its surface properties are discussed to apply for cover-layer incident near-field recording configuration. The effective numerical aperture of a pick up with a solid immersion lens is 1.46, which could cope with the recording density of about 70 GB per disc. The performance of readout signals were investigated, and compared the properties between 320 nm and 200 nm of the track pitch in the substrate.