Patterning device

1. A patterning device for use with a lithographic apparatus, the device comprising:

an absorber portion configured to absorb incident radiation and to reflect a portion of incident radiation, the absorber portion comprising a first layer and a second layer, the first layer of the absorber portion comprising a first material that is different from a second material of the second layer of the absorber portion,

a reflector portion arranged beneath the absorber portion, the reflector portion being configured to reflect incident radiation that passed through the absorber portion; and

a phase tune portion arranged between the reflector portion and the absorber portion, the phase tune portion being configured to induce a phase shift between the radiation reflected by the reflector portion and the portion of radiation reflected by the absorber portion such that the incident radiation reflected by the reflector portion destructively interferes with the portion of radiation reflected by the absorber portion.

2. The device of claim 1 , wherein the phase tune portion comprises a material and/or a thickness selected such that the phase shift induced by the phase tune portion causes destructive interference between the radiation reflected by the reflector portion and the portion of radiation reflected by the absorber portion.

3. The device of claim 1 , wherein the first and second materials are selected such that the absorber portion comprises a reflectivity in a range of about 1 to 20%.

4. The device of claim 1 , wherein the first and second materials are selected such that a thickness of the absorber portion is equal to or less than 25 nm or 30 nm.

5. The device of claim 1 , wherein the absorber portion comprises a plurality of first layers and a plurality of second layers.

6. The device of claim 1 , wherein the/each first layer and the/each second layer are arranged such that the portion of radiation reflected by the absorber portion is in phase or comprises a single phase.

7. The device of claim 1 , wherein the first material of the/each first layer comprises a refractive index and/or absorption coefficient that is higher than a refractive index and/or absorption coefficient of the second material of the/each second layer, wherein the phase tune portion comprises a material that is different from the first material of the/each first layer and/or the second material of the/each second layer.

8. The device of claim 1 , wherein the first and second materials and/or a ratio of a thickness of the first layer to a thickness of the second layer is selected to provide a pre-determined reflectivity.

9. The device of claim 1 , wherein the phase tune portion comprises a material that is the same as the first material of the/each first layer or the second material of the/each second layer or a material of the reflector portion.

10. The device of claim 1 , wherein the phase tune portion comprises a material that is different from the first material of the/each first layer and/or the second material of the/each second layer.

11. The device according to claim 1 , wherein the absorber comprises a third layer and a fourth layer.

12. The device according to claim 11 , wherein one of the third layer or fourth layer is arranged on one of the first layer or second layer and the other one of the third layer or fourth layer is arranged on the one of the third or fourth layer that is arranged on the one of the first layer or second layer.

13. The device according to claim 11 , wherein the first layer and/or fourth layer comprises at least one of Silver, Tantalum, Tantalum-Nitride and Nickel.

14. The device according to claim 11 , wherein the second layer and/or third layer comprises at least one of Aluminum and Silicon.

15. The device of claim 1 , wherein the phase tune portion com the phase tune portion comprises at least one of Ruthenium, Silicon and Molybdenum.

16. The device of claim 1 , wherein the absorber portion is arranged on the phase tune portion and/or reflector portion to form a pattern that is to be projected on a substrate by a lithographic apparatus.

17. The device of claim 1 , wherein the device is provided for use with radiation comprising a wavelength of about 13.5 nm or about 6.7 nm.

18. Use of a patterning device of claim 1 with a lithographic apparatus.

19. A method comprising projecting a patterned beam of radiation onto a substrate, wherein the beam of radiation is patterned by a patterning device according to claim 1 .

20. A method of manufacture of a patterning device for use with a lithographic apparatus, the method comprising:

forming a reflector portion, the reflector portion being configured to reflect incident radiation;

forming an absorber portion, the absorber portion being configured to absorb incident radiation and to reflect a portion of incident radiation, wherein the reflector portion is formed beneath the absorber portion, the absorber portion comprising a first layer and a second layer, the first layer comprising a first material that is different from a second material of the second layer; and

forming a phase tune portion between the reflector portion and the absorber portion, the phase tune portion being configured to induce a phase shift between the radiation reflected by the reflector portion and that has passed through the absorber portion and the portion of radiation reflected by the absorber portion such that the radiation reflected by the reflector portion destructively interferes with the portion of radiation reflected by the absorber portion.