Method for forming an extreme ultraviolet lithography pellicle
According to an aspect of the present disclosure there is provided a method for forming an EUVL pellicle, the method comprising: coating a carbon nanotube, CNT, membrane, and mounting the CNT membrane to a pellicle frame, wherein coating the CNT membrane comprises: pre-coating CNTs of the membrane with a seed material, and forming an outer coating on the pre-coated CNTs, the outer coating covering the pre-coated CNTs, the forming of the outer coating comprising depositing a coating material on the pre-coated CNTs by atomic layer deposition.
1. A method for forming an Extreme Ultraviolet Lithography (EUVL) pellicle, the method comprising:
coating a carbon nanotube (CNT) membrane; and
mounting the CNT membrane to a pellicle frame;
wherein coating the CNT membrane comprises:
pre-coating CNTs of the membrane with a seed material, wherein the seed material is deposited at a rate of 0.7 angstroms/s or lower; and
forming an outer coating on the pre-coated CNTs, the outer coating covering the pre-coated CNTs, the forming of the outer coating comprising depositing a coating material on the pre-coated CNTs by atomic layer deposition.
2. The method according to claim 1 , wherein the seed material is deposited to form a seed layer with an average thickness in a range of 0.5 to 4 nm.
3. The method according to claim 1 , wherein the seed material is deposited to form a seed layer with an average thickness in a range of 0.5 to 3 nm.
4. The method according to claim 1 , wherein the seed material is deposited to form a seed layer with an average thickness in a range of 1 to 2 nm.
5. The method according to claim 1 , wherein the coating material is deposited to form an outer coating with an average thickness in the range of 0.5 to 4 nm.
6. The method according to claim 1 , wherein the coating material is deposited to form an outer coating with an average thickness in the range of 1 to 2 nm.
7. The method according to claim 1 , wherein the seed material is selected from the group of:
C, Zr, ZrN, Hf, HfN, B, B 4 C, BN, Y, YN, La, LaN, SiC, SiN, Ti, TiN, W, Be, Au, Ru, Al, Mo, MoN, Sr, Nb, Sc, Ca, Ni, Ni—P, Ni—B, Cu, and Ag.
8. The method according to claim 1 , wherein the coating material is Zr, Al, B, C, Hf, La, Nb, Mo, Ru, Si, Ti, or Y, or carbides, nitrides, or oxides thereof.
9. The method according to claim 1 , wherein the seed material and the coating material are selected from the group of: Zr seed material and ZrO 2 coating material; B seed material and ZrO 2 coating material, HfO 2 coating material or AhO 3 coating material; B 4 C seed material and ZrO 2 coating material, HfO 2 coating material or AhO 3 coating material; Zr seed material and AhO 3 coating material or ZrAlO 3 coating material; Mo seed material and ZrO 2 coating material.
10. The method according to claim 1 , wherein pre-coating the CNTs with seed material comprises depositing seed material by physical vapor deposition.
11. The method according to claim 10 , wherein the seed material is deposited by thermal evaporation, e-beam evaporation or remote plasma sputtering.
12. The method according to claim 10 , wherein pre-coating the CNTs with seed material comprises depositing seed material from a first side of the membrane and then depositing seed material from a second opposite side of the membrane.
13. A method according to claim 12 , wherein pre-coating is performed in a deposition tool comprising a substrate holder supporting the membrane, and wherein the deposition of seed material is performed during continuous rotation of the substrate holder.
14. The method according to claim 1 , wherein pre-coating the CNTs with seed material comprises depositing seed material by electrochemical deposition or electroplating.
15. The method according to claim 1 , wherein the coating material is deposited by thermal atomic layer deposition.
16. The method according to claim 1 , wherein the CNT membrane is coated prior to being mounted to the pellicle frame.
17. A method for forming an Extreme Ultraviolet Lithography (EUVL) pellicle, the method comprising:
coating a carbon nanotube (CNT) membrane; and
mounting the CNT membrane to a pellicle frame;
wherein coating the CNT membrane comprises:
pre-coating CNTs of the membrane with a seed material by physical vapor deposition, wherein the seed material is deposited at a rate of 0.7 angstroms/s or lower; and
forming an outer coating on the pre-coated CNTs, the outer coating covering the pre-coated CNTs, the forming of the outer coating comprising depositing a coating material on the pre-coated CNTs by atomic layer deposition.