Pellicle comprising silicon carbide nanostructure and related devices and methods
Disclosed are pellicles for use in extreme ultraviolet (EUV) lithography, the pellicles comprising silicon carbide nanostructures, and exhibiting high transmittance of EUV exposure light and high mechanical strength, as well as methods of using these pellicles.
1 . A pellicle useful in an extreme ultraviolet lithography process, the pellicle comprising a membrane that includes silicon carbide nanostructures, wherein the membrane is capable of being self-supporting such that it supports its own weight when being held and suspended by a pellicle frame, and wherein the silicon carbide nanostructures are silicon carbide nanotubes having a core/shell structure comprising silicon carbide outer walls and graphene inner walls resulting from the chemical conversion of carbon nanotubes.
2 . The pellicle of claim 1 , the silicon carbide nanostructures comprising silicon carbide nanotubes.
3 . The pellicle of claim 1 , having a transmittance of at least 80 percent of light having a wavelength of 13.5 nanometer.
4 . The pellicle of claim 1 , the membrane having a thickness that is less than 200 nanometers.
5 . The pellicle of claim 1 , the membrane having a thickness in a range from 50 to 150 nanometers.
6 . The pellicle of claim 1 supported in a planar configuration by a frame at a perimeter of the pellicle.
7 . The pellicle of claim 1 , consisting of the membrane.
8 . The pellicle of claim 1 , that does not include a metal coating.
9 . A lithography mask assembly useful in an extreme ultraviolet lithography process, the mask assembly comprising:
a frame having a perimeter, a first face, a second face, and a thickness between the first face and the second face;
a pellicle disposed at the first face, the pellicle comprising a membrane that includes silicon carbide nanostructures, wherein the membrane is capable of being self-supporting such that it supports its own weight when being held and suspended by a pellicle frame, and wherein the silicon carbide nanostructures are silicon carbide nanotubes having a core/shell structure comprising silicon carbide outer walls and graphene inner walls resulting from the chemical conversion of carbon nanotubes; and
a reflective lithography mask disposed on the second face and having a patterned reflective surface facing the pellicle.
10 . The mask assembly of claim 9 , the silicon carbide nanostructures comprising silicon carbide nanotubes.
11 . The mask assembly of claim 9 , having a transmittance of at least 80 percent of 13.5 nanometer light.
12 . The mask assembly of claim 9 , the membrane having a thickness in a range from 50 to 150 nanometers.
13 . The mask assembly of claim 9 , wherein the pellicle consists of the membrane.
14 . The mask assembly of claim 9 , wherein the pellicle does not include a metal coating.