EUV light source
View Patent ↗An apparatus and method is described which may comprise a plasma produced extreme ultraviolet (“EUV”) light source multilayer collector which may comprise a plasma formation chamber; a shell within the plasma formation chamber in the form of a collector shape having a focus; the shell having a sufficient size and thermal mass to carry operating heat away from the multilayer reflector and to radiate the heat from the surface of the shell on a side of the shell opposite from the focus. The material of the shell may comprise a material selected from a group which may comprise silicon carbide, silicon, Zerodur or ULE glass, aluminum, beryllium, molybdenum, copper and nickel. The apparatus and method may comprise at least one radiative heater directed at the shell to maintain the steady state temperature of the shell within a selected range of operating temperatures.
1. An apparatus comprising:
a plasma produced extreme ultraviolet (“EUV”) light source multilayer collector comprising:
a plasma formation chamber;
a shell within the plasma formation chamber in the form of a collector shape having a focus;
the shell having a sufficient size and thermal mass to carry operating heat away from the multilayer reflector and to radiate the heat from the surface of the shell on a side of the shell opposite from the focus.
2. The apparatus of claim 1 further comprising:
the material of the shell comprises a material selected from a group comprising:
silicon carbide, silicon, Zerodur or ULE glass, aluminum, beryllium, molybdenum, copper and nickel.
3. The apparatus of claim 2 further comprising:
at least one radiative heater directed at the shell to maintain the steady state temperature of the shell within a selected range of operating temperatures.
4. The apparatus of claim 3 further comprising:
the temperatures within the range of temperatures are sufficient to evaporate plasma generation target material from an outer surface of the collector.
5. The apparatus of claim 4 further comprising:
a heat sink adjacent the shell on the side of the shell opposite from the focus absorbing heat radiated from the facing surface of the shell.
6. The apparatus of claim 5 further comprising:
the heat sink forms a part of a heat exchanger transferring heat to a heat transfer fluid supplied from external to the chamber.
7. The apparatus of claim 3 further comprising:
a heat sink adjacent the shell on the side of the shell opposite from the focus absorbing heat radiated from the facing surface of the shell.
8. The apparatus of claim 7 further comprising:
the heat sink forms a part of a heat exchanger transferring heat to a heat transfer fluid supplied from external to the chamber.
9. The apparatus of claim 2 further comprising:
a heat sink adjacent the shell on the side of the shell opposite from the focus absorbing heat radiated from the facing surface of the shell.
10. The apparatus of claim 9 further comprising:
the heat sink forms a part of a heat exchanger transferring heat to a heat transfer fluid supplied from external to the chamber.
11. The apparatus of claim 1 further comprising:
at least one radiative heater directed at the shell to maintain the steady state temperature of the shell within a selected range of operating temperatures.
12. The apparatus of claim 11 further comprising:
the temperatures within the range of temperatures are sufficient to evaporate plasma generation target material from an outer surface of the collector.
13. The apparatus of claim 12 further comprising:
a heat sink adjacent the shell on the side of the shell opposite from the focus absorbing heat radiated from the facing surface of the shell.
14. The apparatus of claim 13 further comprising:
the heat sink forms a part of a heat exchanger transferring heat to a heat transfer fluid supplied from external to the chamber.
15. The apparatus of claim 11 further comprising:
a heat sink adjacent the shell on the side of the shell opposite from the focus absorbing heat radiated from the facing surface of the shell.
16. The apparatus of claim 15 further comprising:
the heat sink forms a part of a heat exchanger transferring heat to a heat transfer fluid supplied from external to the chamber.
17. The apparatus of claim 1 further comprising:
a heat sink adjacent the shell on the side of the shell opposite from the focus absorbing heat radiated from the facing surface of the shell.
18. The apparatus of claim 17 further comprising:
the heat sink forms a part of a heat exchanger transferring heat to a heat transfer fluid supplied from external to the chamber.
19. A method comprising
the method of producing a plasma produced extreme ultraviolet (“EUV”) light source comprising utilizing a collector comprising:
a plasma formation chamber;
a shell within the plasma formation chamber in the form of a collector shape having a focus;
a multilayer stack forming a normal angle of incidence reflector or a grazing angle of incidence reflector in physical and thermal communication with the shell on a side of the shell facing the focus; and
including in the shell a sufficient size and thermal mass to carry operating heat away from the multilayer reflector and to radiate the heat from the surface of the shell on a side of the shell opposite from the focus.
20. An apparatus comprising
a plasma produced extreme ultraviolet (“EUV”) light source collector comprising:
a plasma formation chamber;
a shell within the plasma formation chamber in the form of a collector shape having a focus;
a multilayer stack forming a normal angle of incidence reflector or a grazing angle of incidence reflector in physical and thermal communication with the shell on a side of the shell facing the focus;
a heat sink adjacent the shell on the side of the shell opposite from the focus in radiative thermal communication with the shell.
21. The apparatus of claim 20 further comprising:
the shell comprises a substrate for the multilayer stack.
22. The apparatus of claim 21 further comprising:
the shell having a sufficient size and thermal mass to carry operating heat away from the multilayer reflector and to radiate the heat from the surface of the shell on a side of the shell opposite from the focus.
23. The apparatus of claim 22 further comprising:
a heating element intermediate the shell and the heat sink.
24. The apparatus of claim 23 further comprising:
the heating element comprises a zonal heater differentially heating the shell.
25. The apparatus of claim 21 further comprising:
a heating element intermediate the shell and the heat sink.
26. The apparatus of claim 25 further comprising:
the heating element comprises a zonal heater differentially heating the shell.
27. The apparatus of claim 20 further comprising:
the shell having a sufficient size and thermal mass to carry operating heat away from the multilayer reflector and to radiate the heat from the surface of the shell on a side of the shell opposite from the focus.
28. The apparatus of claim 27 further comprising:
a heating element intermediate the shell and the heat sink.
29. The apparatus of claim 28 further comprising:
the heating element comprises a zonal heater differentially heating the shell.
30. The apparatus of claim 20 further comprising:
a heating element intermediate the shell and the heat sink.
31. The apparatus of claim 30 further comprising:
the heating element comprises a zonal heater differentially heating the shell.