Ion beam system and method of operating an ion beam system
An ion beam system comprises a voltage supply system 7 and at least one beam deflector 39 having at least one first deflection electrode 51 a , 51 b , 51 c and plural second deflection electrodes 52 a , 52 b , 52 c , wherein the voltage supply system is configured to supply different adjustable deflection voltages to the plural second deflection electrodes such that electric deflection fields between the plural second deflection electrodes and the opposite at least one first deflection electrode have a common orientation. The system has a high kinetic energy mode in which a distribution of the electric deflection field has a greater width, a low kinetic energy mode in which a distribution of the electric deflection field has a smaller width.
1. A method of operating an ion beam system, wherein the method comprises:
accelerating ions of an ion beam to a first kinetic energy and deflecting the ion beam into a first direction using an electric deflection field having a first field distribution along the ion beam; and, subsequently,
accelerating ions of the ion beam to a second kinetic energy and deflecting the ion beam into the first direction using the electric deflection field having a second field distribution along the ion beam;
wherein the first kinetic energy is greater than the second kinetic energy; and
wherein a width of the first field distribution is greater than a width of the second field distribution.
2. The method according to claim 1 , wherein the accelerating of the ions of the ion beam to the first kinetic energy and the deflecting of the ion beam into the first direction further comprises deflecting the ion beam into a second direction opposite to the first direction using an electric deflection field having a third field distribution along the ion beam;
wherein the accelerating of the ions of the ion beam to the second kinetic energy and the deflecting of the ion beam into the first direction further comprises deflecting the ion beam into the second direction using an electric deflection field having a fourth field distribution along the ion beam;
wherein a mean position along the ion beam of the third field distribution is located downstream of a mean position along the ion beam of the first field distribution;
wherein a mean position along the ion beam of the fourth field distribution is located downstream of a mean position along the ion beam of the second field distribution.
3. The method according to claim 2 , wherein a distance between the mean position along the ion beam of the first field distribution and the mean position along the ion beam of the third field distribution is greater than a distance between the mean position along the ion beam of the second field distribution and the mean position along the ion beam of the fourth field distribution.
4. The method according to claim 3 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.
5. The method according to claim 2 , wherein the mean position along the ion beam of the fourth field distribution is located downstream of the mean position along the ion beam of the third field distribution.
6. The method according to claim 5 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.
7. The method according to claim 2 , wherein the mean position along the ion beam of the second field distribution is located downstream of the mean position along the ion beam of the first field distribution.
8. The method according to claim 7 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.
9. The method according to claim 2 , further comprising
accelerating ions of the ion beam to a third kinetic energy,
deflecting the ion beam into the first direction using the electric deflection field having a fifth field distribution along the ion beam, and
deflecting the ion beam into the second direction using the electric deflection field having a sixth field distribution along the ion beam;
wherein the second kinetic energy is greater than the third kinetic energy;
wherein the width of the second field distribution is greater than a width of the fifth field distribution;
wherein the width of the fourth field distribution is greater than a width of the sixth field distribution; and
wherein a mean position along the ion beam of the sixth field distribution is located downstream of a mean position along the ion beam of the fifth field distribution.
10. The method according to claim 9 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.
11. The method according to claim 9 , wherein a distance between the mean position along the ion beam of the second field distribution and the mean position along the ion beam of the fourth field distribution is greater than a distance between the mean position along the ion beam of the fifth field distribution and the mean position along the ion beam of the sixth field distribution.
12. The method according to claim 11 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.
13. The method according to claim 9 , wherein the mean position along the ion beam of the fifth field distribution is located downstream of the mean position along the ion beam of the second field distribution.
14. The method according to claim 13 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.
15. The method according to claim 9 , wherein the mean position along the ion beam of the sixth field distribution is located downstream of the mean position along the ion beam of the fourth field distribution.
16. The method according to claim 15 , further comprising focusing the ion beam using a focusing lens located downstream of the electric deflection field.