Extreme ultraviolet pellicle using a thin film and supportive mesh
An extreme ultraviolet (EUV) pellicle including a thin film or membrane and a supportive wire mesh. The pellicle allows EUV radiation to pass through the pellicle to a reticle but prevents particles from passing through the pellicle. A buffer gas supports the film against the wire mesh. The film or membrane may be embedded with support fibers or beams.
1. An apparatus comprising:
a membrane having a first side and a second side, the membrane being adapted to allow extreme ultraviolet radiation to pass from the first side to the second side, the membrane being adapted to prevent particles from passing from the first side to the second side, the membrane being less than 200 nanometers in thickness; and
a mesh of wires supporting the first side of the membrane.
2. The apparatus of claim 1 , further comprising an extreme ultraviolet radiation source, wherein the membrane allows extreme ultraviolet radiation to pass from the first side to the second side of the membrane.
3. The apparatus of claim 1 , wherein the wires have diameters of about 25 microns.
4. The apparatus of claim 1 , wherein the wires are spaced about 1 millimeter apart from each other.
5. The apparatus of claim 1 , wherein the mesh of wires and membrane are elastic.
6. The apparatus of claim 5 , further comprising a gas source operable to produce a gas that exerts pressure on the second side of the membrane and holds the membrane up against the mesh of wires.
7. The apparatus of claim 6 , wherein the gas source produces a repulsive jet through any pinholes in the membrane and prevents particles on the first side from entering the pinholes.
8. The apparatus of claim 6 , wherein the gas source removes particles from the second side of the membrane.
9. The apparatus of claim 1 , further comprising:
a reticle on the second side of the membrane;
a frame supporting edges of the membrane and the mesh of wires a pre-determined distance above the reticle.
10. The apparatus of claim 9 , wherein the frame supports edges of the membrane and the mesh of wires about one to ten centimeters above the reticle.
11. The apparatus of claim 9 , wherein the frame includes laser-drilled holes through which the wires are threaded.
12. The apparatus of claim 9 , wherein ends of the wires are bonded to the frame.
13. The apparatus of claim 9 , wherein the frame includes a spring-loaded tension apparatus to hold the mesh of wires.
14. The apparatus of claim 1 , wherein the membrane comprises embedded fibers.
15. The apparatus of claim 1 , wherein the membrane comprises embedded support beams.
16. The apparatus of claim 1 , wherein the membrane comprises a silicon layer.
17. The apparatus of claim 1 , wherein the membrane comprises a silicon layer, a silicon dioxide layer, and a plurality of support beams.
18. The apparatus of claim 1 , wherein the membrane comprises a substantially elastic, cured polymer-chain layer.
19. The apparatus of claim 1 , wherein the membrane comprises an organic layer of hydrophobic polymer on a substrate.
20. The apparatus of claim 19 , wherein the membrane further comprises a fibrous material layer.