Lithographic apparatus, device manufacturing method and computer program

1. An exposure apparatus, comprising:

a radiation source configured to produce a plurality of radiation beams having individually controllable intensities;

a projection system configured to project each of the radiation beams onto a respective location on a target; and

a controller configured to calculate a target intensity value for each of the radiation beams to expose the target to a desired pattern and to control the radiation source to emit beams with the target intensity values, wherein the controller calculates the target intensity values using a calculated or measured value of the position and/or rotation of each of the locations relative to the projection system and the controller calculates the target intensity values using a function for each radiation beam that models radiation coupling to that beam from a neighboring beam.

2. The apparatus according to claim 1 , wherein the function depends on the position and/or rotation of each of the locations relative to the projection system.

3. The apparatus according to claim 2 , wherein the controller comprises a look-up table that stores a plurality of functions for each radiation beam, the controller configured to select a function for each radiation beam from the look-up table according to the calculated or measured value of the position and/or rotation of the respective location.

4. The apparatus according to claim 1 , wherein the function is a convolution or deconvolution kernel.

5. The apparatus according to claim 1 , further comprising a position sensor configured to measure the position and/or rotation of the locations on the target relative to the projection system while the radiation beams are being projected onto the target.

6. The apparatus according to claim 1 , further comprising:

a first memory arranged to store data representing a map of a surface profile of the target;

a second memory arranged to store data representing a trajectory of the target; and

a position calculator arranged to calculate a position and/or rotation of each location from the map and the trajectory.

7. The apparatus according to claim 1 , wherein the controller calculates the target intensity values using a calculated or measured value of the positions of the locations relative to the projection system and the positions of the locations relative to the projection system are distances from a reference plane in a direction perpendicular to the reference plane.

8. The apparatus according to claim 1 , wherein the target is a target portion on a substrate.

9. The apparatus according to claim 1 , wherein the target is a layer of donor material spaced apart from a substrate on which a device is to be formed.

10. The apparatus according to claim 1 , wherein the radiation source comprises a programmable patterning device configured to provide the plurality of radiation beams.

11. The apparatus according to claim 10 , wherein the programmable patterning device comprises a controllable element to selectively provide the beams of radiation.

12. The apparatus according to claim 10 , wherein the programmable patterning device comprises a plurality of self-emissive contrast devices.

13. A device manufacturing method in which a target is to be irradiated with a desired pattern, the method comprising:

calculating an intensity value for each of a plurality of radiation beams to be used to irradiate the target, the calculation being performed based on a calculated or measured value of a position and/or rotation relative to a projection system of a plurality of locations on the target and the calculation using a function for each radiation beam that models radiation coupling to that beam from a neighboring beam; and

projecting the radiation beams having the calculated intensity values onto respective ones of the locations using the projection system.

14. The method according to claim 13 , wherein the function depends on the position and/or rotation of each of the locations relative to the projection system.

15. The method according to claim 14 , comprising selecting the function for each radiation beam from a look-up table according to the calculated or measured value of the position and/or rotation of the respective location, the look-up table storing a plurality of functions for each radiation beam.

16. A non-transitory data storage medium comprising a computer program stored therein to calculate an intensity value for each of a plurality of radiation beams to be used to irradiate a target, the computer program comprising code to instruct a processor to perform the calculation using a calculated or measured value of a position and/or rotation relative to a projection system of each of a plurality of locations on the target and to perform the calculation using a function for each radiation beam that models radiation coupling to that beam from a neighboring beam.

17. The storage medium according to claim 16 , wherein the function is a convolution or deconvolution kernel.

18. The storage medium according to claim 16 , wherein the function depends on the position and/or rotation of each of the locations relative to the projection system.

19. The storage medium according to claim 16 , further comprising code configured to calculate a position and/or rotation of each location from a map of a surface profile of the target and data representing a trajectory of the target.

20. The storage medium according to claim 16 , wherein the code is configured to perform the calculation using a calculated or measured value of the positions of the locations relative to the projection system and the positions of the locations relative to the projection system are distances from a reference plane in a direction perpendicular to the reference plane.