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. The exposing and developing of a specified thickness of 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 made from a replication process that includes creation of a master disk, creation of a first-generation stamper from the master disk and creation of a second-generation stamper from the first-generation stamper, the replica disk comprising:
a replica substrate having a first major surface and a second major surface, the first major surface including a surface relief pattern defined by adjacent lands and grooves, the surface relief pattern having a track pitch less than 425 nanometers, wherein the grooves extend down into the replica substrate, the grooves including groove bottoms and the lands including land tops, wherein the land tops are wider than the groove bottoms.
2. The replica disk of claim 1 , wherein the land tops are generally flat and coplanar.
3. The replica disk of claim 1 , wherein the grooves define a groove depth that is greater than 20 nanometers.
4. The replica disk of claim 1 , wherein widths of the land tops are greater than 80 nanometers.
5. The replica disk of claim 1 , wherein widths of the land tops are greater than 250 nanometers.
6. The replica disk of claim 1 , wherein the replica disk is created from the second-generation stamper.
7. A replica disk made from a replication process that includes creation of a master disk, creation of a first-generation stamper from the master disk and creation of a second-generation stamper from the first-generation stamper, the replica disk comprising:
a replica substrate having a first niajor surface and a second major surface, the first major surface including a surface relief pattern defined by adjacent lands and grooves, the surface relief pattern having a track pitch less than 425 nanometers, wherein the grooves extend down into the replica substrate, the grooves including groove bottoms and the lands including land tops, wherein a width of the land tops is greater than 25 percent of the track pitch.
8. The replica disk of claim 7 , wherein the land tops are flat and coplanar and wherein the land tops include sharp corners.
9. The replica disk of claim 7 , wherein the grooves define a groove depth between 20 and 120 nanometers.
10. The replica disk of claim 7 , wherein the width of the land tops is greater than 35 percent of the track pitch.
11. The replica disk of claim 10 , wherein the width of the land tops is greater than 50 percent of the track pitch.
12. The replica disk of claim 7 , wherein the replica disk is created from the second-generation stamper.
13. A replica disk made from a replication process that includes creation of a laser etched master disk, creation of a first-generation stamper from the laser etched master disk and creation of a second-generation stamper from the first-generation stamper, the replica disk comprising:
a replica substrate having a first major surface and a second major surface, the first major surface including a surface relief pattern defined by adjacent lands and grooves, the surface relief pattern defining a track pitch less than 2 multiplied by a laser spot size associated with a laser used to perform laser etching of the laser etched master disk, wherein the track pitch is less than 700 nanometers.
14. The replica disk of claim 13 , wherein the track pitch of the surface relief pattern is less than 425 nanometers and a width of tops of the lands is greater than 25 percent of the track pitch.
15. The replica disk of claim 14 , wherein the width of the tops of the lands is greater than 35 percent of the track pitch.
16. The replica disk of claim 13 , wherein tops of the lands are flat and coplanar and include sharp corners.
17. The replica disk of claim 13 , wherein the track pitch is less than 1.6 multiplied by the laser spot size.
18. The replica disk of claim 13 , wherein the replica disk is created from the second-generation stamper.
19. A replica disk comprising:
a replica substrate having a first major surface and a second major surface, the first major surface including a surface pattern defined by lands and grooves, the surface relief pattern defining a track pitch less than approximately 700 nanometers,
wherein groove depths of the grooves are less than approximately 120 nanometers deep, and
wherein land tops of the lands are less than approximately 200 nanometers wide.
20. The replica disk of claim 19 , wherein the track pitch is less than approximately 425 nanometers.
21. The replica disk of claim 19 , wherein the groove depths of the grooves are less than approximately 100 nanometers deep.
22. The replica disk of claim 21 , wherein the groove depths of the grooves are less than approximately 80 nanometers deep.
23. The replica disk of claim 22 , wherein the groove depths of the grooves are less than approximately 60 nanometers deep.
24. The replica disk of claim 19 , wherein land tops of the lands are less than approximately 180 nanometers wide.
25. The replica disk of claim 24 , wherein land tops of the lands are less than approximately 160 nanometers wide.
26. The replica disk of claim 25 , wherein land tops of the lands are less than approximately 140 nanometers wide.
27. The replica disk of claim 26 , wherein land tops of the lands are less than approximately 120 nanometers wide.
28. The replica disk of claim 27 , wherein land tops of the lands are less than approximately 100 nanometers wide.
29. A replica disk made from a replication process that includes creation of a master disk, creation of a first-generation stamper from the master disk and creation of a second-generation stamper from the first-generation stamper, the replica disk comprising:
a replica substrate having a first major surface and a second major surface, the first major surface including a surface relief pattern defined by lands that correspond to interrupted grooves formed in the master disk, wherein land tops of the lands are less than approximately 200 nanometers wide.
30. The replica disk of claim 29 , wherein a track pitch of the replica disk defined by radially adjacent lands is less than approximately 425 nanometers.
31. The replica disk of claim 29 , wherein land tops of the lands are less than approximately 180 nanometers wide.
32. The replica disk of claim 31 , wherein land tops of the lands are less than approximately 160 nanometers wide.
33. The replica disk of claim 32 , wherein land tops of the lands are less than approximately 140 nanometers wide.
34. The replica disk of claim 33 , wherein land tops of the lands are less than approximately 120 nanometers wide.
35. The replica disk of claim 34 , wherein land tops of the lands are less than approximately 100 nanometers wide.