Pellicle and method for producing pellicle
A silicon single crystal film having a crystal plane as its principal plane, the crystal plane being inclined at 3 to 5° from any lattice plane belonging to {100} planes or {111} planes is used as a pellicle film. The silicon single crystal having such a crystal plane as its principal plane has effective bond density and Young's modulus thereof which are about 40% to about 50% higher than those of a silicon single crystal with <100> orientation, and therefore a cleavage and crack do not easily occur. Moreover, the silicon single crystal has a high chemical resistance such as hydrofluoric acid resistance, and hardly causes an etch pit and void. Accordingly, the present invention can provide a pellicle comprising a pellicle film for EUV having high transmission, and excellent mechanical and chemical stability, as well as having a high yield, and being practical also in cost.
1. A pellicle, comprising:
a silicon single crystal film as a pellicle film,
wherein a principal plane of the silicon single crystal film is a crystal plane inclined at 3 to 5° from any lattice plane belonging to {100} planes or {111} planes,
wherein when the lattice plane belongs to a {100} plane, the crystal plane is inclined at 3 to 5° in a <111> direction.
2. The pellicle according to claim 1 , wherein the lattice plane belongs to the {111} planes, and the crystal plane is inclined at 3 to 5° in a <110> direction.
3. The pellicle according to claim 1 , wherein the silicon single crystal film is obtained by making an SOI substrate into a thin film.
4. The pellicle according to claim 1 , wherein the silicon single crystal film has an absorption coefficient of 0.005/nm or less for light having a wavelength of 13.5 nm.
5. The pellicle according to claim 1 , comprising a protection film on at least one principal plane of the silicon single crystal film.
6. The pellicle according to claim 5 , wherein the protection film has an absorption coefficient of 0.05/nm or less for light having a wavelength of 13.5 nm.
7. The pellicle according to claim 5 , wherein the protection film consists of at least one material selected from the group consisting of SiC, SiO 2 , Si 3 N 4 , SiON, Y 2 O 3 , YN, Mo, Ru, and Rh.
8. A method of producing a pellicle, comprising:
providing a pellicle film retaining portion on a top side of an SOI substrate comprising the top side and a bottom side, that has, on one principal plane, a silicon single crystal film having a crystal plane as its principal plane, the crystal plane being inclined at 3 to 5° from any lattice plane belonging to {100} planes or {111} planes; and
forming the silicon single crystal film as a pellicle film by removing a support substrate from the bottom side of the SOI substrate,
wherein when the lattice plane belongs to a {100} plane, the crystal plane is inclined at 3 to 5° in a <111> direction.
9. The method of claim 8 , further comprising forming a protection film on at least one surface of the silicon single crystal film.
10. The method of claim 9 , wherein the forming a protection film is performed by coating a film with at least one material selected from the group consisting of SiC, SiO 2 , Si 3 N 4 , SiON, Y 2 O 3 , YN, Mo, Ru, and Rh.
11. The method of claim 10 , wherein a coating method of the protection film is a gas cluster ion beam evaporation method.
12. The pellicle of claim 1 , having a thickness of 20 to 150 nm.
13. The pellicle of claim 1 , having a thickness of 20 to 70 nm.
14. The method of claim 8 , wherein the pellicle has a thickness of 20 to 150 nm.
15. The method of claim 8 , wherein the pellicle has a thickness of 20 to 70 nm.
16. The method of claim 8 , wherein the lattice plane of the pellicle belongs to the {111} planes, and the crystal plane is inclined at 3 to 5° in a <110> direction.
17. The pellicle of claim 1 , having an EUV transmittance of 50% or more.
18. The method of claim 8 , wherein the pellicle has an EUV transmittance of 50% or more.
19. The pellicle of claim 1 , wherein the lattice plane belongs to the {111} planes.
20. The method of claim 8 , wherein the lattice plane of the pellicle belongs to the {111} planes.