Multi-level stamper for improved thermal imprint lithography
View Patent ↗A stamper/imprinter for use in performing thermal imprint lithography of a substrate/workpiece surface to form a pattern of features in first portions of the surface intended to receive the pattern, without incurring random formation of undesired, disordered features in second portions of the substrate/workpiece surface not intended to receive the pattern, comprising an imprinting surface configured to substantially prevent formation of gaps between the imprinting surface and the second portions of the surface during stamping/imprinting. Embodiments include stampers/imprinters with a multilevel imprinting surface comprises a first portion having a first level for forming the pattern of features in the first portions of the surface and a second portion having a second level for substantially preventing formation of gaps between the imprinting surface and the second portions of the surface during stamping/imprinting.
1. A method of performing thermal imprint lithography of a substrate/workpiece surface to form a pattern of features in first portions of said surface intended to receive said pattern, without incurring random formation of undesired, disordered features in second portions of said substrate/workpiece surface not intended to receive said pattern, which method comprises utilizing a stamper/imprinter having an imprinting surface which is configured to substantially prevent formation of gaps between said imprinting surface of said stamper/imprinter and said second portions of said substrate/workpiece surface during stamping/imprinting, wherein said stamper/imprinter comprises:
a main body; and
a multilevel imprinting surface including a negative image of said pattern of features to be formed in said first portions of said substrate/workpiece surface.
2. The method according to claim 1 , wherein:
said multilevel imprinting surface comprises a first portion having a first level for forming said pattern of features in said first portions of said substrate/workpiece surface and a second portion having a second level for substantially preventing formation of gaps between said imprinting surface of said stamper/imprinter and said second portions of said substrate/workpiece surface during stamping/imprinting.
3. The method according to claim 2 , wherein:
said first level is below said second level.
4. The method according to claim 3 , wherein:
said second portion of said multilevel imprinting surface further comprises grooves formed to a shallow depth therein, for substantially preventing occurrence of shear forces between said stamper/imprinter and said substrate/workpiece surface arising from relative movement therebetween during thermal cycling between lower and higher temperatures during said thermal imprint lithography.
5. The method according to claim 4 , wherein:
said substrate/workpiece surface comprises a layer of a thermoplastic polymer resist material thereon, said shallow depth grooves formed in said second portion of said multilevel imprinting surface being replicated in said layer of thermoplastic polymer resist material, wherein said layer of thermoplastic polymer resist material is sufficiently thick as to prevent removal of portions of said substrate/workpiece surface beneath said shallow depth grooves during subsequent processing for pattern formation.
6. The method according to claim 5 , wherein:
said subsequent processing for pattern formation comprises a material removal process.
7. The method according to claim 6 , wherein:
said material removal process is selected from a group consisting of sputter etching, reactive ion etching, ion-beam etching, and wet chemical etching.
8. The method according to claim 5 , wherein:
said substrate/workpiece is a disk-shaped substrate for a hard disk data/information storage and retrieval medium; and
said pattern of features in said first portions of said surface of said disk-shaped substrate comprises a servo pattern.
9. The method according to claim 8 , wherein:
said disk-shaped substrate comprises a material selected from the group consisting of Al, Al/NiP, Al-based alloys, other metals, other metal alloys, polymers, polymer-based materials, glass, ceramics, and composites and laminates thereof;
said thermoplastic polymer resist material comprises a poly(methylmethacrylate); and
said imprinting surface of said stamper/imprinter comprises a material selected from the group consisting of Ni, Ni-based alloys, other metals, other metal alloys, dielectrics, semiconductors, ceramics, and composites and laminates thereof.
10. A stamper/imprinter for use in performing thermal imprint lithography of a substrate/workpiece surface to form a pattern of features in first portions of said surface intended to receive said pattern, without incurring random formation of undesired, disordered features in second portions of said substrate/workpiece surface not intended to receive said pattern, comprising:
an imprinting surface which is configured to substantially prevent formation of gaps between said imprinting surface of said stamper/imprinter and said second portions of said substrate/workpiece surface during stamping/imprinting.
11. The stamper as in claim 10 , comprising:
a main body; and
a multilevel imprinting surface including a negative image of said pattern of features to be formed in said first portions of said substrate/workpiece surface.
12. The stamper as in claim 11 , wherein:
said multilevel imprinting surface comprises a first portion having a first level for forming said pattern of features in said first portions of said substrate/workpiece surface and a second portion having a second level for substantially preventing formation of gaps between said imprinting surface of said stamper/imprinter and said second portions of said substrate/workpiece surface during stamping/imprinting.
13. The stamper/imprinter as in claim 12 , wherein:
said first level is below said second level.
14. The stamper/imprinter as in claim 13 , wherein:
said second portion of said multilevel imprinting surface further comprises grooves formed to a shallow depth therein, for substantially preventing occurrence of shear forces between said stamper/imprinter and said substrate/workpiece surface arising from relative movement therebetween during thermal cycling between lower and higher temperatures during said thermal imprint lithography.
15. The stamper/imprinter as in claim 11 , wherein:
said pattern of features in said first portions of said imprinting surface comprises a servo pattern for a disk-shaped data/information storage and retrieval medium.
16. The stamper/imprinter as in claim 11 , wherein:
said imprinting surface of said stamper/imprinter comprises a material selected from the group consisting of Ni, Ni-based alloys, other metals, other metal alloys, dielectrics, semiconductors, ceramics, and composites and laminates thereof.
17. A stamper/imprinter for performing thermal imprint lithography, comprising:
a main body; and
means for forming a pattern of features in first portions of a substrate/workpiece surface intended to receive said pattern, without incurring random formation of undesired, disordered features in second portions of said substrate/workpiece surface not intended to receive said pattern.
18. The stamper/imprinter as in claim 17 , wherein:
said means comprises means for forming a servo pattern of a disk-shaped data/information storage and retrieval medium.
19. The stamper/imprinter as in claim 17 , wherein:
said means further comprises means for substantially preventing occurrence of shear forces between said stamper/imprinter and said substrate/workpiece surface arising from relative movement therebetween during thermal cycling between lower and higher temperatures during said thermal imprint lithography.