A purifier is described for use in a gas processing application. The purifier comprises a chamber having a gas inlet and a gas outlet. A series of baffles are arranged in the chamber and coated with a getter material selected for its ability to react with species to be removed from a gas stream and form stable compounds. The chamber also houses a source of the getter material, which is periodically activated to refresh the coating of getter material on the baffles.
1. A purifier for use in a gas processing application comprising:
a chamber having a gas inlet and a gas outlet;
at least one baffle arranged in the chamber and having a coating comprising a getter material to react with species to be removed from a gas stream and form stable compounds;
a source of the getter material within the chamber; and
means for vaporizing the source of the getter material to refresh the coating of getter material on the at least one baffle.
2. The purifier according to claim 1 further comprising a collector wherein the means for vaporizing the source of the getter material is arranged to produce an electric arc between the source of the getter material and the collector.
3. The purifier according to claim 2 wherein the collector extends about the source of the getter material.
4. The purifier according to claim 2 further comprising an inner wall of the chamber wherein the collector comprises at least part of the inner wall of the chamber.
5. The purifier according to claim 1 wherein the source of the getter material comprises a rod, the at least one baffle being arranged about the rod.
6. The purifier according to claim 5 wherein the rod extends longitudinally through the chamber.
7. The purifier according to claim 6 wherein the rod is substantially co-axial with the chamber.
8. The purifier according to claim 1 wherein the means for vaporizing the source of the getter material comprises a controller.
9. The purifier according to claim 8 wherein the controller is adapted to activate at predefined time intervals.
10. The purifier according to claim 9 further comprising a sensor for monitoring a process wherein the source of the getter material is vaporized when a predefined change in the process gas is detected by the sensor.
11. The purifier according to claim 10 wherein the sensor is located within the chamber.
12. The purifier according to claim 1 wherein the at least one baffle is adapted to create a convoluted path for gas flowing through the chamber.
13. The purifier according to claim 1 wherein the getter material comprises at least one metal selected from the group of metals consisting of Ti, Ta and alloys thereof.
14. The purifier according to claim 1 wherein the getter material comprises at least one metal selected from the group of metals consisting of Fe Cr and alloys thereof.
15. A semiconductor processing system comprising:
a process chamber having a purified gas inlet; and
a purifier comprising:
a housing;
a gas inlet;
a gas outlet upstream of the purified gas inlet;
at least one baffle arranged within the housing and comprising a getter material;
a source of the getter material; and
means for applying an electric potential across the source of the getter material and the housing, thereby vaporizing the source of the getter material to refresh the coating of getter material on the at least one baffle.
16. The semiconductor processing system of claim 15 wherein the source of the getter material is a rod.
17. The semiconductor processing system of claim 15 wherein the source of the getter material is an electrode.
18. The semiconductor processing system of claim 15 wherein the at least one baffle is arranged to form a convoluted flow path.
19. The semiconductor processing system of claim 18 wherein at least one baffle is arranged about the source of the getter material.
20. The semiconductor processing system of claim 15 wherein the means for applying an electric potential comprises a power supply.
21. The semiconductor processing system of claim 15 wherein the means for applying an electric potential comprises a controller for activating the source of the getter material at predefined time intervals.
22. The semiconductor processing system of claim 15 wherein the getter material comprises at least one metal selected from the group of metals consisting of Ti, Ta, Zr, Fe, Cr and alloys thereof.