Reverse optical mastering for data storage disk replicas
View Patent ↗A data storage master disk and method of making a data storage master disk. The data storage disk master is for use in a data storage disk replication process. The data storage disk molding processes produces replica disks having a surface relief pattern with replica lands and replica grooves. The method includes providing a master substrate. The master substrate is at least partially covered with a layer of photosensitive material. A surface relief pattern having master lands and master grooves is recorded in the data storage disk master, including the steps of exposing and developing the photosensitive material is controlled to form master grooves extending down to a substrate interface between the master substrate and the layer of photosensitive material, such that the width of the master grooves at the substrate interface corresponds to a desired width of the replica lands.
1. A replica disk comprising:
a replica substrate having a first surface that includes a surface pattern defined by lands and grooves,
wherein the surface pattern has a track pitch that is less than 425 nanometers,
wherein the grooves have depths less than 120 nanometers, and
wherein the lands and grooves are inverse of corresponding features on a master disk used in a process of creating the replica disk.
2. The replica disk of claim 1 , wherein the depths of the grooves are less than 40 nanometers.
3. The replica disk of claim 1 , wherein the lands have tops with widths between 100 nanometers and 200 nanometers.
4. The replica disk of claim 3 , wherein the tops of the lands have widths that are greater than 25 percent of the track pitch.
5. The replica disk of claim 4 , wherein the tops of the lands have widths that are greater than 35 percent of the track pitch.
6. The replica disk of claim 1 , wherein the lands have tops that are substantially flat and coplanar.
7. The replica disk of claim 1 , wherein the depths of the grooves are less than 80 nanometers.
8. The replica disk of claim 3 , wherein the tops of the lands have widths between 140 nanometers and 180 nanometers.
9. The replica disk of claim 1 , wherein the depths of the grooves are less than 60 nanometers.
10. The replica disk of claim 1 , wherein the depths of the grooves are greater than 20 nanometers.
11. A replica disk comprising:
a replica substrate having a first surface that includes a surface pattern defined by lands and grooves,
wherein the surface pattern has a track pitch that is less than 425 nanometers,
wherein tops of the lands define widths that are less than 200 nanometers,
wherein the widths of the tops of the lands are greater than 25 percent of the track pitch, and
wherein the lands and grooves are inverse of corresponding features on a master disk used in a process of creating the replica disk.
12. The replica disk of claim 11 , wherein the widths of the tops of the lands are greater than 35 percent of the track pitch.
13. The replica disk of claim 11 , wherein the tops of the lands are substantially flat and coplanar.
14. The replica disk of claim 11 , wherein the tops the lands have widths that are greater than 100 nanometers.