Method to fabricate a mould for lithography by nano-imprinting
A nano-imprint device including at least: a substrate, having a surface, on the substrate, a plurality of nano-trenches parallel two by two, each nano-trench extending in a longitudinal direction and being delimited laterally by side walls, the nano-trenches and the side walls being directed substantially perpendicular to the surface of the substrate, each nano-trench comprising a bottom surface with at least one first and one second level in a direction perpendicular to the substrate, respectively of depth h 1 and h 2 >h 1 , measured relative to the top of the side walls, and the bottom surfaces of the nano-trenches, of the least deep level (h 1 ) being in a first type of material, the side walls being in a second type of material.
1. A nano-imprint device comprising at least:
a substrate, having a surface,
on the substrate, a plurality of nano-trenches parallel two by two, each nano-trench extending in a longitudinal direction and being delimited in a lateral direction by side walls, the nano-trenches and the side walls being directed substantially perpendicular to said surface of the substrate, each nano-trench comprising a bottom surface,
in a cross-sectional view along the longitudinal direction, the bottom surface of each nano-trench has at least one first and one second level in a direction perpendicular to the substrate, respectively of depth h 1 and h 2 >h 1 , measured relative to the top of the side walls,
in a cross-sectional view along the lateral direction, the bottom surface of each nano-trench has only one level that is at the depth h 1 or h 2 , and
the bottom surfaces of the nano-trenches, of the least deep level h 1 being in a first material, the side walls being in a second material.
2. The device according to claim 1 , wherein said plurality of nano-trenches separated by side walls form an array of patterns and of nano-trenches, each portion of nano-trench of depth h 2 being offset from a portion of an adjacent nano-trench by a period P*, in said longitudinal direction.
3. The device according to claim 1 , wherein deepest parts, of depth h 2 , of the nano-trenches have a length shorter than period P*.
4. The device according to claim 1 , wherein each deep part of depth h 2 lying at one end of a nano-trench is delimited by four faces,
one face in said first material, of height h 2 −h 1 ,
two faces formed by two side walls of said second material, and
one face of said first material, of depth h 2 , and whose top is at a same level, or substantially at a same level, as a top of the side walls surrounding the nano-trench.
5. The device according to claim 1 , wherein a width of the nano-trenches is equal to or less than 10 nm+/−2 nm.
6. The device according to claim 1 , wherein each nano-trench with depth h 1 is disposed in a first region and each nano-trench with depth h 2 is disposed in a second region, different from the first region and adjacent to the first region.
7. The device according to claim 1 , wherein the bottom surface of each nano-trench, in both the longitudinal direction and the lateral direction, only includes said first material.
8. A nano imprint device comprising at least:
a substrate, having a surface,
on this substrate, a plurality of nano-trenches parallel two by two, each nano-trench extending in a longitudinal direction and being delimited laterally by side walls, the nano-trenches and the side walls being directed substantially perpendicular to said surface of the substrate, each nano-trench comprising at least one first and one second level in a direction perpendicular to the substrate, respectively of depth h 1 and h 2 >h 1 , measured relative to the top of the side walls, and
a bottom of the nano-trenches, of the least deep level h 1 being in a first material, the side walls being in a second material, the first material able to be etched selectively relative to the second material forming the walls of the nano-trench, and
said plurality of nano-trenches separated by side walls forming an array of patterns and of nano-trenches, each portion of nano-trench of depth h 2 being offset from a portion of an adjacent nano-trench by a period P*, in said longitudinal direction.
9. The device according to claim 8 , wherein deepest parts, of depth h 2 , of the nano-trenches have a length shorter than period P*.
10. The device according to claim 8 , wherein each deep part of depth h 2 lying at one end of a nano-trench, and is delimited by four faces,
one face in said first material, of height h 2 −h 1 ,
two faces formed by two side walls of said second material,
one face of said first material, of depth h 2 , and whose top is at same level, or substantially at same level, as a top of the side walls surrounding the nano-trench.
11. The device according to claim 8 , wherein a width of the nano-trenches is equal to or less than 10 nm+/−2 nm.