Superstrate including a body and layers and methods of forming and using the same
A superstrate can include a body, a first layer, and a second layer, wherein the first layer is disposed between the body and the second layer. Each of the first and second layers has a proximal surface and a distal surface opposite the proximal surface, wherein the body is closer to the proximal surface than to the distal surface. An Ra of the distal surface of the second layer is less than an Ra of the distal surface of the first layer. In a method of making the superstrate, the relatively high Ra of the distal surface of the first layer may be related to the process or equipment used in forming the first layer. The second layer can be formed using another superstrate, where the Ra of the distal surface of the second layer is substantially the same as the contact surface of the other superstrate.
1. A superstrate, comprising:
a body of the superstrate, wherein the body has an upper surface that does not have recessions and protrusions;
a first buffer layer overlying the body and having a proximal surface and a distal surface opposite the proximal surface, wherein the body is closer to the proximal surface of the first buffer layer than to the distal surface of the first buffer layer, and the first buffer layer includes an organic compound;
a second compensation layer overlying the first buffer layer to fill any elevation changes along the distal surface thereof and having a proximal surface and a distal surface opposite the proximal surface, wherein the body is closer to the proximal surface of the second compensation layer than to the distal surface of the second compensation layer; and
a third protection layer overlying the second compensation layer and having a proximal surface and a distal surface opposite the proximal surface, wherein the body is closer to the proximal surface of the third protection layer than to the distal surface of the third protection layer,
wherein an Ra of the distal surface of the first buffer layer is greater than an Ra of each of the upper surface of the body, the distal surface of the second compensation layer, and the distal surface of the third protection layer, wherein the Ra is an arithmetic average surface roughness.
2. The superstrate of claim 1 , wherein along the distal surface of the first buffer layer, the first buffer layer does not have an intentional pattern of recessions and protrusions.
3. The superstrate of claim 1 , wherein the Ra of the distal surface of the second compensation layer is at most 0.20 nm.
4. The superstrate of claim 3 , wherein:
the proximal surface of the first buffer layer is along the upper surface of the body, and the Ra of the upper surface of the body is at most 0.2 nm,
the proximal surface of the second compensation layer is along the distal surface of the first buffer layer, and
the proximal surface of the third protection layer is along the distal surface of the second compensation layer, and the Ra of the distal surface of the third protection layer is at most 0.2 nm.
5. The superstrate of claim 1 , wherein a nanotopography of the distal surface of the third protection layer is less than a nanotopography of the distal surface of the first buffer layer.
6. The superstrate of claim 5 , wherein a nanotopography of the distal surface of the third protection layer is at most 5.9 nm on a 2 mm lateral scale.
7. The superstrate of claim 1 , wherein the first buffer layer comprises an acrylic polymer.
8. The superstrate of claim 7 , wherein the second compensation layer comprises a polymerizable compound.
9. The superstrate of claim 7 , wherein the second compensation layer comprises a polyacrylate.
10. The superstrate of claim 1 , wherein:
the first buffer layer is formed by thermally curing a first precursor, and
the second compensation layer is formed curing a second precursor, wherein curing is performed using actinic radiation having a wavelength in a range from 10 nm to 1000 nm.
11. The superstrate of claim 1 , wherein the third protection layer comprises an oxide, a nitride, an oxynitride, or a fluoropolymer.
12. A method of making a first superstrate, comprising:
forming a first buffer layer along a surface of an upper surface of a body of the first superstrate, wherein the upper surface does not have recessions and protrusions, the first buffer layer has a proximal surface and a distal surface opposite the proximal surface, and the body is closer to the proximal surface of the first buffer layer than to the distal surface of first buffer layer; and
forming a second compensation layer along the distal surface of the first buffer layer to fill any elevation changes along the distal surface thereof, wherein the second compensation layer has a proximal surface and a distal surface opposite the proximal surface, and the body is closer to the proximal surface of the second compensation layer than to the distal surface of second compensation layer; and
forming a third protection layer along the distal surface of the second compensation layer, wherein the third protection layer has a proximal surface and a distal surface opposite the proximal surface, and the body is closer to the proximal surface of the third protection layer than to the distal surface of third protection layer,
wherein after forming the third protection layer, an Ra of the distal surface of the first buffer layer is greater than an Ra of each of the upper surface of the body, the distal surface of the second compensation layer, and the distal surface of the third protection layer, wherein the Ra is an arithmetic average surface roughness.
13. The method of claim 12 , wherein forming the first buffer layer comprises:
depositing a precursor for the first buffer layer along the surface of the body, wherein the precursor has an exposed surface opposite the body; and
curing the precursor using curing energy to form the first buffer layer, wherein during curing, a solid object is not in contact with the exposed surface of the precursor.
14. The method of claim 12 , wherein forming the first buffer layer comprises:
depositing a precursor for the first buffer layer along the surface of the body; and
curing the precursor using curing energy to form the first buffer layer, wherein during curing, the precursor is not uniformly exposed to the curing energy.
15. The method of claim 12 , wherein forming the second compensation layer comprises:
depositing droplets of a precursor for the second compensation layer;
contacting the precursor with a second superstrate; and
curing the precursor to form the second compensation layer, wherein the second superstrate contacts the precursor during curing.
16. The method of claim 12 , wherein forming the third protection layer comprises:
depositing a precursor for the third protection layer along a surface of a second superstrate;
contacting the precursor with the second compensation layer; and
curing the precursor to form the third protection layer, wherein the second superstrate contacts the precursor during curing.
17. The method of claim 12 , wherein the Ra of the distal surface of the third protection layer is at most 0.20 nm.
18. The method of claim 16 , wherein the first superstrate has an ultraviolet transmittance of at least 70%, and the second superstrate is a silicon wafer.
19. A method of making an article, comprising:
dispensing a formable material over a patterned layer of a workpiece, wherein the workpiece includes a substrate and the patterned layer overlies the substrate;
contacting the formable material with the superstrate of claim 1 ;
exposing the formable material to actinic radiation to form a planarization layer while the distal surface of the third protection layer of the superstrate is in contact with the formable material to form the planarization layer; and
processing the workpiece to complete formation of the article.
20. The method of claim 19 , wherein:
the proximal surface of the first buffer layer is along the upper surface of the body, and the Ra of the upper surface of the body is at most 0.2 nm,
the proximal surface of the second compensation layer is along the distal surface of the first buffer layer, and
the proximal surface of the third protection layer is along the distal surface of the second compensation layer, and the Ra of the distal surface of the third protection layer is at most 0.2 nm.