Substrate holder, lithographic apparatus, device manufacturing method, and method of manufacturing a substrate holder
A substrate holder for a lithographic apparatus has a planarization layer provided on a surface thereof. The planarization layer provides a smooth surface for the formation of a thin film stack forming an electronic component. The thin film stack comprises an (optional) isolation layer, a metal layer forming an electrode, a sensor, a heater, a transistor or a logic device, and a top isolation layer.
1. A substrate holder for use in a lithographic apparatus, the substrate holder comprising:
a main body having a surface;
a plurality of burls projecting from the surface and having end surfaces to support a substrate;
a planarization layer provided on at least part of the surface of the main body; and
a thin film stack formed or attached on top of the planarization layer and forming an electric or electronic component, the thin film stack horizontally spaced by a gap from an adjacent burl.
2. The substrate holder according to claim 1 , wherein the thin film stack includes a conductive layer.
3. The substrate holder according to claim 2 , wherein the conductive layer has a thickness in the range of from about 20 nm to about 1 μm.
4. The substrate holder according to claim 2 , wherein the thin film stack includes an isolation layer provided on the surface of the conductive layer furthest from the planarization layer.
5. The substrate holder according to claim 4 , wherein the isolation layer is formed of a material or a combination of materials selected from the group consisting of: benzocyclobutene; perhydropolysilazane, SiO x , parylene and polyimide.
6. The substrate holder according to claim 4 , wherein the isolation layer has a thickness in the range of from about 0.1 μm to about 100 μm.
7. The substrate holder according to claim 2 , wherein the thin film stack includes an isolation layer between the conductive layer and the planarization layer.
8. The substrate holder according to claim 1 , wherein the thin film stack forms a plurality of electric or electronic components.
9. The substrate holder according to claim 8 , wherein a first electric or electronic component and a second electric or electronic component of the plurality of electric or electronic components are arranged in a single layer of the thin film stack.
10. The substrate holder according to claim 8 , wherein a first electric or electronic component and a second electric or electronic component of the plurality of electric or electronic components are arranged in two separate layers of the thin film stack.
11. The substrate holder according to claim 1 , wherein the electric or electronic component comprises a sensor comprising a conductor arranged to reduce or minimize pickup of electromagnetic interference.
12. The substrate holder according to claim 1 , wherein the planarization layer provided on at least part of the surface of the main body to cover an area encompassing the plurality of burls, the planarization layer provided between the burls but not covering the end surfaces of the plurality of burls.
13. A device manufacturing method using a lithographic apparatus, the method comprising:
projecting a beam patterned by a patterning device onto a substrate while holding the substrate in a substrate holder,
wherein the substrate holder comprises: a main body having a surface; a plurality of burls projecting from the surface and having end surfaces to support a substrate; a planarization layer provided on at least part of the surface of the main body; and a thin film stack formed or attached on top of the planarization layer and forming an electric or electronic component, the thin film stack horizontally spaced by a gap from an adjacent burl.
14. A substrate holder for use in a lithographic apparatus, the substrate holder comprising:
a main body having a surface, the surface having a surface roughness;
a plurality of burls projecting from the surface and having end surfaces to support a substrate; and
a planarization layer provided on at least part of the surface of the main body, the planarization layer comprises a first sub-layer to at least partially fill in the surface roughness and a second sub-layer on top of the first sub-layer, the second sub-layer having a different composition than the first sub-layer; and
an electric or electronic component formed or attached on top of the planarization layer, the top of the planarization layer being substantially smooth.
15. The substrate holder according to claim 14 , wherein the planarization layer further comprises a third sub-layer.
16. The substrate holder according to claim 14 , wherein the first sub-layer is formed of benzocyclobutene.
17. The substrate holder according to claim 14 , wherein the second sub-layer is formed of SiO x .
18. A method of manufacturing a substrate holder for use in a lithographic apparatus, the method comprising:
providing a main body having a surface and a plurality of burls projecting from the surface and having end surfaces to support a substrate, the surface having a surface roughness; and
forming a planarization layer on at least part of the surface of the main body, wherein forming the planarization layer comprises forming a first sub-layer to at least partially fill in the surface roughness and a second sub-layer on top of the first sub-layer, the second sub-layer formed using a different method of application than the first sub-layer; and
forming or attaching an electric or electronic component on top of the planarization layer, the top of the planarization layer being substantially smooth.
19. The method according to claim 18 , wherein forming the first sub-layer, or forming the second sub-layer, or forming the first and second sub-layers comprises spraying a solution of a polymer or polymer-precursor.
20. A method of manufacturing a substrate holder for use in a lithographic apparatus, the method comprising:
providing a main body having a surface and a plurality of burls projecting from the surface and having end surfaces to support a substrate, the surface having a surface roughness; and
forming a planarization layer on at least part of the surface of the main body, the top of the planarization layer being substantially smooth,
wherein forming the planarization layer comprises:
forming a curable first sub-layer to at least partially fill in the surface roughness,
separately from forming the first sub-layer, baking the first sub-layer to cure it, and
after the baking, forming a second sub-layer on top of the first sub-layer, the second sub-layer formed at or below the top of the planarization layer.